1
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Jennison C, Armstrong JM, Dankwa DA, Hertoghs N, Kumar S, Abatiyow BA, Naung M, Minkah NK, Swearingen KE, Moritz R, Barry AE, Kappe SHI, Vaughan AM. Plasmodium GPI-anchored micronemal antigen is essential for parasite transmission through the mosquito host. Mol Microbiol 2024; 121:394-412. [PMID: 37314965 PMCID: PMC11076100 DOI: 10.1111/mmi.15078] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/03/2023] [Accepted: 05/08/2023] [Indexed: 06/16/2023]
Abstract
Plasmodium parasites, the eukaryotic pathogens that cause malaria, feature three distinct invasive forms tailored to the host environment they must navigate and invade for life cycle progression. One conserved feature of these invasive forms is the micronemes, apically oriented secretory organelles involved in egress, motility, adhesion, and invasion. Here we investigate the role of GPI-anchored micronemal antigen (GAMA), which shows a micronemal localization in all zoite forms of the rodent-infecting species Plasmodium berghei. ∆GAMA parasites are severely defective for invasion of the mosquito midgut. Once formed, oocysts develop normally, however, sporozoites are unable to egress and exhibit defective motility. Epitope-tagging of GAMA revealed tight temporal expression late during sporogony and showed that GAMA is shed during sporozoite gliding motility in a similar manner to circumsporozoite protein. Complementation of P. berghei knockout parasites with full-length P. falciparum GAMA partially restored infectivity to mosquitoes, indicating conservation of function across Plasmodium species. A suite of parasites with GAMA expressed under the promoters of CTRP, CAP380, and TRAP, further confirmed the involvement of GAMA in midgut infection, motility, and vertebrate infection. These data show GAMA's involvement in sporozoite motility, egress, and invasion, implicating GAMA as a regulator of microneme function.
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Affiliation(s)
- Charlie Jennison
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Janna M. Armstrong
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Dorender A. Dankwa
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Nina Hertoghs
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Sudhir Kumar
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Biley A. Abatiyow
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Myo Naung
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Victoria, Parkville, Australia
- Department of Medical Biology, University of Melbourne, Victoria, Carlton, Australia
- Department of Global Health, University of Washington, Washington, Seattle, USA
| | - Nana K. Minkah
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Kristian E. Swearingen
- Institute of Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Victoria, Geelong, Australia
| | - Robert Moritz
- Institute of Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Victoria, Geelong, Australia
| | - Alyssa E. Barry
- Department of Global Health, University of Washington, Washington, Seattle, USA
- Institute for Systems Biology, Washington, Seattle, USA
| | - Stefan H. I. Kappe
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
- Burnet Institute, Victoria, Melbourne, Australia
- Department of Pediatrics, University of Washington, Washington, Seattle, USA
| | - Ashley M. Vaughan
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
- Burnet Institute, Victoria, Melbourne, Australia
- Department of Pediatrics, University of Washington, Washington, Seattle, USA
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2
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Ruybal-Pesántez S, McCann K, Vibin J, Siegel S, Auburn S, Barry AE. Molecular markers for malaria genetic epidemiology: progress and pitfalls. Trends Parasitol 2024; 40:147-163. [PMID: 38129280 DOI: 10.1016/j.pt.2023.11.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/13/2023] [Accepted: 11/14/2023] [Indexed: 12/23/2023]
Abstract
Over recent years, progress in molecular markers for genotyping malaria parasites has enabled informative studies of epidemiology and transmission dynamics. Results have highlighted the value of these tools for surveillance to support malaria control and elimination strategies. There are many different types and panels of markers available for malaria parasite genotyping, and for end users, the nuances of these markers with respect to 'use case', resolution, and accuracy, are not well defined. This review clarifies issues surrounding different molecular markers and their application to malaria control and elimination. We describe available marker panels, use cases, implications for different transmission settings, limitations, access, cost, and data accuracy. The information provided can be used as a guide for molecular epidemiology and surveillance of malaria.
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Affiliation(s)
- Shazia Ruybal-Pesántez
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, UK; Institute of Microbiology, Universidad San Francisco de Quito, Quito, Ecuador
| | - Kirsty McCann
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; Centre for Innovation in Infectious Disease and Immunology Research (CIIDIR), Institute for Mental and Physical Health and Clinical Translation (IMPACT) and School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Jessy Vibin
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; Centre for Innovation in Infectious Disease and Immunology Research (CIIDIR), Institute for Mental and Physical Health and Clinical Translation (IMPACT) and School of Medicine, Deakin University, Geelong, Victoria, Australia
| | | | - Sarah Auburn
- Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia; Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
| | - Alyssa E Barry
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; Centre for Innovation in Infectious Disease and Immunology Research (CIIDIR), Institute for Mental and Physical Health and Clinical Translation (IMPACT) and School of Medicine, Deakin University, Geelong, Victoria, Australia.
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3
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Toure M, Shaffer JG, Sanogo D, Keita S, Keita M, Kane F, Traore B, Dabitao D, Kone A, Doumbia CO, Keating J, Yukich J, Hansson HH, Barry AE, Diakité M, Alifrangis M, Doumbia S. Seasonal Malaria Chemoprevention Therapy in Children Up To 9 Years of Age: Protocol for a Cluster-Randomized Trial Study. JMIR Res Protoc 2024; 13:e51660. [PMID: 38252481 PMCID: PMC10845024 DOI: 10.2196/51660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 01/23/2024] Open
Abstract
BACKGROUND Seasonal malaria chemoprevention (SMC) is recommended by the World Health Organization for the sub-Sahel region in sub-Saharan Africa for preventing malaria in children 3 months old to younger than 5 years. Since 2016, the Malian National Malaria Control Program has deployed SMC countrywide during its high malaria transmission season at a rate of 4 monthly cycles annually. The standard SMC regimen includes sulfadoxine-pyrimethamine (SP) plus amodiaquine (AQ). Resistance against SP is suspected to be rising across West Africa; therefore, assessing the effectiveness of an alternative antimalarial drug for SMC is needed to provide a second-line regimen when it is ultimately needed. It is not well understood whether SMC effectively prevents malaria in children aged 5 years or older. OBJECTIVE The primary goal of the study is to compare 2 SMC regimens (SP-AQ and dihydroartemisinin-piperaquine [DHA-PQ]) in preventing uncomplicated Plasmodium falciparum malaria in children 3 months to 9 years old. Secondly, we will assess the possible use of DHA-PQ as an alternative SMC drug in areas where resistance to SP or AQ may increase following intensive use. METHODS The study design is a 3-arm cluster-randomized design comparing the SP-AQ and DHA-PQ arms in 2 age groups (younger than 5 years and 5-9 years) and a control group for children aged 5-9 years. Standard SMC (SP-AQ) for children younger than 5 years was provided to the control arm, while SMC with SP-AQ was delivered to children aged 3 months to 9 years (arm 2), and SMC with DHA-PQ will be implemented in study arm 3 for children up to 9 years of age. The study was performed in Mali's Koulikoro District, a rural area in southwest Mali with historically high malaria transmission rates. The study's primary outcome is P falciparum incidence for 2 SMC regimens in children up to 9 years of age. Should DHA-PQ provide an acceptable alternative to SP-AQ, a plausible second-line prevention option would be available in the event of SP resistance or drug supply shortages. A significant byproduct of this effort included bolstering district health information systems for rapid identification of severe malaria cases. RESULTS The study began on July 1, 2019. Through November 2022, a total of 4556 children 3 months old to younger than 5 years were enrolled. Data collection ended in spring 2023, and the findings are expected to be published later in early 2024. CONCLUSIONS Routine evaluation of antimalarial drugs is needed to establish appropriate SMC age targets. The study goals here may impact public health policy and provide alternative therapies in the event of drug shortages or resistance. TRIAL REGISTRATION ClinicalTrials.gov NCT04149106, https://clinicaltrials.gov/ct2/show/NCT04149106. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) DERR1-10.2196/51660.
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Affiliation(s)
- Mahamoudou Toure
- University Clinical Research Center, Universite des Sciences, des Techniques et des Technologies, Bamako, Mali
| | - Jeffrey G Shaffer
- Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, United States
| | - Daouda Sanogo
- University Clinical Research Center, Universite des Sciences, des Techniques et des Technologies, Bamako, Mali
| | - Soumba Keita
- University Clinical Research Center, Universite des Sciences, des Techniques et des Technologies, Bamako, Mali
| | - Moussa Keita
- University Clinical Research Center, Universite des Sciences, des Techniques et des Technologies, Bamako, Mali
| | - Fousseyni Kane
- University Clinical Research Center, Universite des Sciences, des Techniques et des Technologies, Bamako, Mali
| | - Bourama Traore
- University Clinical Research Center, Universite des Sciences, des Techniques et des Technologies, Bamako, Mali
| | - Djeneba Dabitao
- University Clinical Research Center, Universite des Sciences, des Techniques et des Technologies, Bamako, Mali
| | - Aissata Kone
- Mali National Malaria Control Program, Bamako, Mali
| | - Cheick Oumar Doumbia
- University Clinical Research Center, Universite des Sciences, des Techniques et des Technologies, Bamako, Mali
| | - Joseph Keating
- Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, United States
| | - Joshua Yukich
- Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, United States
| | - Helle H Hansson
- Center for Medical Parasitology, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Alyssa E Barry
- Institute for Mental and Physical Health and Clinical Translation (IMPACT) and School of Medicine, Deakin University, Geelong, Melbourne, Australia
- Life Sciences Discipline, Burnet Institute, Melbourne, Australia
| | - Mahamadou Diakité
- University Clinical Research Center, Universite des Sciences, des Techniques et des Technologies, Bamako, Mali
| | - Michael Alifrangis
- Center for Medical Parasitology, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Seydou Doumbia
- University Clinical Research Center, Universite des Sciences, des Techniques et des Technologies, Bamako, Mali
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4
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Hamilton WL, Ishengoma DS, Parr JB, Bridges DJ, Barry AE. Nanopore sequencing for malaria molecular surveillance: opportunities and challenges. Trends Parasitol 2023; 39:996-1000. [PMID: 37865609 DOI: 10.1016/j.pt.2023.09.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 09/25/2023] [Accepted: 09/25/2023] [Indexed: 10/23/2023]
Abstract
Nanopore-based sequencing platforms offer the potential for affordable malaria molecular surveillance (MMS) in resource-limited settings to track and ultimately counteract emerging threats, such as drug resistance and diagnostic escape. Here, we discuss opportunities and challenges to implementing MMS using nanopore sequencing, highlighting priority areas for technical development and innovation.
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Affiliation(s)
- William L Hamilton
- Wellcome Sanger Institute, Wellcome Trust Genome Campus, Hinxton, CB10 1RQ, UK; University of Cambridge, Department of Medicine, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, UK; Cambridge University Hospitals NHS Foundation Trust, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, UK.
| | - Deus S Ishengoma
- National Institute for Medical Research, Dar es Salaam, Tanzania; Harvard T.H. Chan School of Public Health, Boston, MA, USA; Faculty of Pharmaceutical Sciences, Monash University, VIC, Australia
| | - Jonathan B Parr
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Daniel J Bridges
- PATH, National Malaria Elimination Center, Chainama Hospital Grounds, Great East Road, Lusaka, Zambia
| | - Alyssa E Barry
- Centre for Innovation in Infectious Disease and Immunology Research, IMPACT, School of Medicine, Deakin University, Geelong, VIC 3220, Australia; Burnet Institute, Melbourne, VIC 3000, Australia.
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5
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Ling DB, Nguyen W, Looker O, Razook Z, McCann K, Barry AE, Scheurer C, Wittlin S, Famodimu MT, Delves MJ, Bullen HE, Crabb BS, Sleebs BE, Gilson PR. A Pyridyl-Furan Series Developed from the Open Global Health Library Block Red Blood Cell Invasion and Protein Trafficking in Plasmodium falciparum through Potential Inhibition of the Parasite's PI4KIIIB Enzyme. ACS Infect Dis 2023; 9:1695-1710. [PMID: 37639221 PMCID: PMC10496428 DOI: 10.1021/acsinfecdis.3c00138] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Indexed: 08/29/2023]
Abstract
With the resistance increasing to current antimalarial medicines, there is an urgent need to discover new drug targets and to develop new medicines against these targets. We therefore screened the Open Global Health Library of Merck KGaA, Darmstadt, Germany, of 250 compounds against the asexual blood stage of the deadliest malarial parasite Plasmodium falciparum, from which eight inhibitors with low micromolar potency were found. Due to its combined potencies against parasite growth and inhibition of red blood cell invasion, the pyridyl-furan compound OGHL250 was prioritized for further optimization. The potency of the series lead compound (WEHI-518) was improved 250-fold to low nanomolar levels against parasite blood-stage growth. Parasites selected for resistance to a related compound, MMV396797, were also resistant to WEHI-518 as well as KDU731, an inhibitor of the phosphatidylinositol kinase PfPI4KIIIB, suggesting that this kinase is the target of the pyridyl-furan series. Inhibition of PfPI4KIIIB blocks multiple stages of the parasite's life cycle and other potent inhibitors are currently under preclinical development. MMV396797-resistant parasites possess an E1316D mutation in PfPKI4IIIB that clusters with known resistance mutations of other inhibitors of the kinase. Building upon earlier studies that showed that PfPI4KIIIB inhibitors block the development of the invasive merozoite parasite stage, we show that members of the pyridyl-furan series also block invasion and/or the conversion of merozoites into ring-stage intracellular parasites through inhibition of protein secretion and export into red blood cells.
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Affiliation(s)
- Dawson B. Ling
- Burnet Institute,
Melbourne, Victoria3004, Australia
- Department of Microbiology and Immunology,
University of Melbourne, Melbourne, Victoria3010,
Australia
| | - William Nguyen
- The Walter and Eliza Hall Institute of
Medical Research, Melbourne, Victoria3052,
Australia
- Department of Medical Biology, The
University of Melbourne, Parkville, Victoria3010,
Australia
| | - Oliver Looker
- Burnet Institute,
Melbourne, Victoria3004, Australia
| | - Zahra Razook
- Burnet Institute,
Melbourne, Victoria3004, Australia
- School of Medicine and Institute for Mental and
Physical Health and Clinical Translation, Deakin University,
Waurn Ponds, Victoria3216, Australia
| | - Kirsty McCann
- Burnet Institute,
Melbourne, Victoria3004, Australia
- School of Medicine and Institute for Mental and
Physical Health and Clinical Translation, Deakin University,
Waurn Ponds, Victoria3216, Australia
| | - Alyssa E. Barry
- Burnet Institute,
Melbourne, Victoria3004, Australia
- School of Medicine and Institute for Mental and
Physical Health and Clinical Translation, Deakin University,
Waurn Ponds, Victoria3216, Australia
| | - Christian Scheurer
- Swiss Tropical and Public Health
Institute, Allschwil, 4123Switzerland
- University of Basel, Basel,
4001Switzerland
| | - Sergio Wittlin
- Swiss Tropical and Public Health
Institute, Allschwil, 4123Switzerland
- University of Basel, Basel,
4001Switzerland
| | - Mufuliat Toyin Famodimu
- Department of Infection Biology, Faculty of Infectious
Diseases, London School of Hygiene and Tropical Medicine, Kepel
Street, London, WC1E 7HT, U.K.
| | - Michael J Delves
- Department of Infection Biology, Faculty of Infectious
Diseases, London School of Hygiene and Tropical Medicine, Kepel
Street, London, WC1E 7HT, U.K.
| | - Hayley E. Bullen
- Burnet Institute,
Melbourne, Victoria3004, Australia
- Department of Microbiology and Immunology,
University of Melbourne, Melbourne, Victoria3010,
Australia
| | - Brendan S. Crabb
- Burnet Institute,
Melbourne, Victoria3004, Australia
- Department of Microbiology and Immunology,
University of Melbourne, Melbourne, Victoria3010,
Australia
- Department of Immunology and Pathology,
Monash University, Melbourne, Victoria3800,
Australia
| | - Brad E. Sleebs
- The Walter and Eliza Hall Institute of
Medical Research, Melbourne, Victoria3052,
Australia
- Department of Medical Biology, The
University of Melbourne, Parkville, Victoria3010,
Australia
| | - Paul R. Gilson
- Burnet Institute,
Melbourne, Victoria3004, Australia
- Department of Microbiology and Immunology,
University of Melbourne, Melbourne, Victoria3010,
Australia
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6
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Dans MG, Piirainen H, Nguyen W, Khurana S, Mehra S, Razook Z, Geoghegan ND, Dawson AT, Das S, Parkyn Schneider M, Jonsdottir TK, Gabriela M, Gancheva MR, Tonkin CJ, Mollard V, Goodman CD, McFadden GI, Wilson DW, Rogers KL, Barry AE, Crabb BS, de Koning-Ward TF, Sleebs BE, Kursula I, Gilson PR. Sulfonylpiperazine compounds prevent Plasmodium falciparum invasion of red blood cells through interference with actin-1/profilin dynamics. PLoS Biol 2023; 21:e3002066. [PMID: 37053271 PMCID: PMC10128974 DOI: 10.1371/journal.pbio.3002066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 04/25/2023] [Accepted: 03/06/2023] [Indexed: 04/15/2023] Open
Abstract
With emerging resistance to frontline treatments, it is vital that new antimalarial drugs are identified to target Plasmodium falciparum. We have recently described a compound, MMV020291, as a specific inhibitor of red blood cell (RBC) invasion, and have generated analogues with improved potency. Here, we generated resistance to MMV020291 and performed whole genome sequencing of 3 MMV020291-resistant populations. This revealed 3 nonsynonymous single nucleotide polymorphisms in 2 genes; 2 in profilin (N154Y, K124N) and a third one in actin-1 (M356L). Using CRISPR-Cas9, we engineered these mutations into wild-type parasites, which rendered them resistant to MMV020291. We demonstrate that MMV020291 reduces actin polymerisation that is required by the merozoite stage parasites to invade RBCs. Additionally, the series inhibits the actin-1-dependent process of apicoplast segregation, leading to a delayed death phenotype. In vitro cosedimentation experiments using recombinant P. falciparum proteins indicate that potent MMV020291 analogues disrupt the formation of filamentous actin in the presence of profilin. Altogether, this study identifies the first compound series interfering with the actin-1/profilin interaction in P. falciparum and paves the way for future antimalarial development against the highly dynamic process of actin polymerisation.
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Affiliation(s)
- Madeline G Dans
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Henni Piirainen
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - William Nguyen
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Sachin Khurana
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Somya Mehra
- Burnet Institute, Melbourne, Victoria, Australia
| | - Zahra Razook
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | | | | | - Sujaan Das
- Ludwig Maximilian University, Faculty of Veterinary Medicine, Munich, Germany
| | | | - Thorey K Jonsdottir
- Burnet Institute, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia
| | - Mikha Gabriela
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | - Maria R Gancheva
- Research Centre for Infectious Diseases, The University of Adelaide, Adelaide, Australia
| | | | - Vanessa Mollard
- School of Biosciences, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Geoffrey I McFadden
- School of Biosciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Danny W Wilson
- Research Centre for Infectious Diseases, The University of Adelaide, Adelaide, Australia
| | - Kelly L Rogers
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Alyssa E Barry
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | - Brendan S Crabb
- Burnet Institute, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia
| | - Tania F de Koning-Ward
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | - Brad E Sleebs
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Inari Kursula
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Paul R Gilson
- Burnet Institute, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia
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7
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Barry AE. Malaria outbreak in Laos caused by formerly rare artemisinin resistant strains of Plasmodium falciparum. The Lancet Infectious Diseases 2022; 23:513-514. [PMID: 36462527 DOI: 10.1016/s1473-3099(22)00761-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 11/09/2022] [Indexed: 12/02/2022]
Affiliation(s)
- Alyssa E Barry
- Institute for Mental and Physical Health and Clinical Translation and School of Medicine, Deakin University, Geelong, VIC 3220, Australia; Burnet Institute, Melbourne, VIC, Australia.
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8
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Doumbia S, Toure M, Sogoba N, Alifrangis M, Diakite M, Diarra A, Keita M, Konaté D, Diawara SI, Thiam SM, Keita S, Tounkara M, Cissé I, Sanogo V, Magassa MH, Barry AE, Winch PJ, Marker HC, Shaffer JG, Traoré SF, Müller GC, Cui L, Beier JC, Mihigo J. The West Africa ICEMR Partnerships for Guiding Policy to Improve the Malaria Prevention and Control. Am J Trop Med Hyg 2022; 107:84-89. [PMID: 36228908 PMCID: PMC9662222 DOI: 10.4269/ajtmh.21-1330] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 07/06/2022] [Indexed: 12/01/2022] Open
Abstract
The Mali National Malaria Control Program (NMCP) recently established a phased set of goals for eliminating malaria in Mali by 2030. Over the past decade, the scale-up of NMCP-led malaria control interventions has led to considerable progress, as evidenced by multiple malariometric indicators. The West Africa International Center of Excellence in Malaria Research (WA-ICEMR) is a multidisciplinary research program that works closely with the NMCP and its partners to address critical research needs for malaria control. This coordinated effort includes assessing the effectiveness of control interventions based on key malaria research topics, including immune status, parasite genetic diversity, insecticide and drug resistance, diagnostic accuracy, malaria vector populations and biting behaviors, and vectorial capacity. Several signature accomplishments of the WA-ICEMR include identifying changing malaria age demographic profiles, testing innovative approaches to improve control strategies, and providing regular reporting on drug and insecticide resistance status. The NMCP and WA-ICEMR partnership between the WA-ICEMR and the NMCP offers a comprehensive research platform that informs the design and implementation of malaria prevention and control research programs. These efforts build local expertise and capacity for the next generation of malaria researchers and guide local policy, which is crucial in sustaining efforts toward eliminating malaria in West Africa.
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Affiliation(s)
- Seydou Doumbia
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Mahamoudou Toure
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Nafomon Sogoba
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Michael Alifrangis
- Centre for Medical Parasitology, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark; Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Mahamadou Diakite
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Ayouba Diarra
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Moussa Keita
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Drissa Konaté
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Sory I. Diawara
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Sidibé M’Baye Thiam
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Soumba Keita
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Moctar Tounkara
- Department of Public Health, Faculty of Medicine and Odontostomatology, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Idrissa Cissé
- National Malaria Control Program, Ministry of Health, Bamako, Mali
| | - Vincent Sanogo
- National Malaria Control Program, Ministry of Health, Bamako, Mali
| | | | | | - Peter J. Winch
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Hannah C. Marker
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Jeffrey G. Shaffer
- School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana
| | - Sékou F. Traoré
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Günter C. Müller
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Liwang Cui
- Division of Infectious Diseases and Internal Medicine, Department of Internal Medicine, University of South Florida, Tampa, Florida
| | - John C. Beier
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, Florida
| | - Jules Mihigo
- U.S. President’s Malaria Initiative, United States Agency for International Development Office, Bamako, Mali
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9
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Doumbia S, Sogoba N, Diakite M, Toure M, Keita M, Konaté D, Diawara SI, Diarra A, Sanogo D, Kane F, Diakite SAS, Traore K, Thiam SM, Traoré SF, Cisse I, Mihigo J, Coulibaly MB, Dabitao D, Alifrangis M, Barry AE, Müller GC, Beier JC, Shaffer JG. A Decade of Progress Accelerating Malaria Control in Mali: Evidence from the West Africa International Center of Excellence for Malaria Research. Am J Trop Med Hyg 2022; 107:75-83. [PMID: 36228923 PMCID: PMC9662231 DOI: 10.4269/ajtmh.21-1309] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 07/06/2022] [Indexed: 11/07/2022] Open
Abstract
This article highlights over a decade of signature achievements by the West Africa International Centers for Excellence in Malaria Research (WA-ICEMR) and its partners toward guiding malaria prevention and control strategies. Since 2010, the WA-ICEMR has performed longitudinal studies to monitor and assess malaria control interventions with respect to space-time patterns, vector transmission indicators, and drug resistance markers. These activities were facilitated and supported by the Mali National Malaria Control Program. Research activities included large-scale active and passive surveillance and expanded coverage of universal long-lasting insecticide-treated bed nets and seasonal malaria chemoprevention (SMC). The findings revealed substantial declines in malaria occurrence after the scale-up of control interventions in WA-ICEMR study sites. WA-ICEMR studies showed that SMC using sulfadoxine-pyrimethamine plus amodiaquine was highly effective in preventing malaria among children under 5 years of age. An alternative SMC regimen (dihydroartemisinin plus piperaquine) was shown to be potentially more effective and provided advantages for acceptability and compliance over the standard SMC regimen. Other findings discussed in this article include higher observed multiplicity of infection rates for malaria in historically high-endemic areas, continued antimalarial drug sensitivity to Plasmodium falciparum, high outdoor malaria transmission rates, and increased insecticide resistance over the past decade. The progress achieved by the WA-ICEMR and its partners highlights the critical need for maintaining current malaria control interventions while developing novel strategies to disrupt malaria transmission. Enhanced evaluation of these strategies through research partnerships is particularly needed in the wake of reported artemisinin resistance in Southeast Asia and East Africa.
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Affiliation(s)
- Seydou Doumbia
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Nafomon Sogoba
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Mahamadou Diakite
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Mahamoudou Toure
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Moussa Keita
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Drissa Konaté
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Sory I. Diawara
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Ayouba Diarra
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Daouda Sanogo
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Fousseyni Kane
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Seidina A. S. Diakite
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Karim Traore
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Sidibé M’Baye Thiam
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Sékou F. Traoré
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Idrissa Cisse
- National Malaria Control Program, Ministry of Health, Bamako, Mali
| | - Jules Mihigo
- U.S. President’s Malaria Initiative, United States Agency for International Development Office, Bamako, Mali
| | - Mamadou B. Coulibaly
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Djeneba Dabitao
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Michael Alifrangis
- Centre for Medical Parasitology, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark; Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | | | - Günter C. Müller
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - John C. Beier
- Miller School of Medicine, University of Miami, Miami, Florida
| | - Jeffrey G. Shaffer
- School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana
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10
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Tichkule S, Myung Y, Naung MT, Ansell BRE, Guy AJ, Srivastava N, Mehra S, Cacciò SM, Mueller I, Barry AE, van Oosterhout C, Pope B, Ascher DB, Jex AR. VIVID: a web application for variant interpretation and visualisation in multidimensional analyses. Mol Biol Evol 2022; 39:6697981. [PMID: 36103257 PMCID: PMC9514033 DOI: 10.1093/molbev/msac196] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Large-scale comparative genomics- and population genetic studies generate enormous amounts of polymorphism data in the form of DNA variants. Ultimately, the goal of many of these studies is to associate genetic variants to phenotypes or fitness. We introduce VIVID, an interactive, user-friendly web application that integrates a wide range of approaches for encoding genotypic to phenotypic information in any organism or disease, from an individual or population, in three-dimensional (3D) space. It allows mutation mapping and annotation, calculation of interactions and conservation scores, prediction of harmful effects, analysis of diversity and selection, and 3D visualization of genotypic information encoded in Variant Call Format on AlphaFold2 protein models. VIVID enables the rapid assessment of genes of interest in the study of adaptive evolution and the genetic load, and it helps prioritizing targets for experimental validation. We demonstrate the utility of VIVID by exploring the evolutionary genetics of the parasitic protist Plasmodium falciparum, revealing geographic variation in the signature of balancing selection in potential targets of functional antibodies.
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Affiliation(s)
- Swapnil Tichkule
- Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research , Melbourne , Australia
- Department of Medical Biology, University of Melbourne , Melbourne , Australia
| | - Yoochan Myung
- Systems and Computational Biology, Bio21 Institute, University of Melbourne , Melbourne , Australia
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes , Melbourne , Australia
| | - Myo T Naung
- Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research , Melbourne , Australia
- Department of Medical Biology, University of Melbourne , Melbourne , Australia
| | - Brendan R E Ansell
- Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research , Melbourne , Australia
| | - Andrew J Guy
- School of Science, RMIT University , Melbourne , Australia
| | - Namrata Srivastava
- Department of Data Science and AI, Monash University , Melbourne , Australia
| | - Somya Mehra
- Life Sciences Discipline, Burnet Institute , Melbourne , Australia
| | - Simone M Cacciò
- Department of Infectious Disease, Istituto Superiore di Sanità , Rome , Italy
| | - Ivo Mueller
- Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research , Melbourne , Australia
| | - Alyssa E Barry
- Life Sciences Discipline, Burnet Institute , Melbourne , Australia
- Institute of Mental and Physical Health and Clinical Translation (IMPACT) and School of Medicine, Deakin University , Geelong , Australia
| | - Cock van Oosterhout
- School of Environmental Sciences, University of East Anglia, Norwich Research Park , Norwich , UK
| | - Bernard Pope
- Melbourne Bioinformatics, University of Melbourne , Melbourne , Australia
- Australian BioCommons , Sydney , Australia
- Department of Clinical Pathology, University of Melbourne , Melbourne , Australia
- Department of Surgery (Royal Melbourne Hospital), University of Melbourne , Melbourne , Australia
| | - David B Ascher
- Systems and Computational Biology, Bio21 Institute, University of Melbourne , Melbourne , Australia
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes , Melbourne , Australia
| | - Aaron R Jex
- Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research , Melbourne , Australia
- Faculty of Veterinary and Agricultural Sciences, University of Melbourne , Melbourne , Australia
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11
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Han J, Munro JE, Kocoski A, Barry AE, Bahlo M. Population-level genome-wide STR discovery and validation for population structure and genetic diversity assessment of Plasmodium species. PLoS Genet 2022; 18:e1009604. [PMID: 35007277 PMCID: PMC8782505 DOI: 10.1371/journal.pgen.1009604] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 01/21/2022] [Accepted: 12/14/2021] [Indexed: 11/18/2022] Open
Abstract
Short tandem repeats (STRs) are highly informative genetic markers that have been used extensively in population genetics analysis. They are an important source of genetic diversity and can also have functional impact. Despite the availability of bioinformatic methods that permit large-scale genome-wide genotyping of STRs from whole genome sequencing data, they have not previously been applied to sequencing data from large collections of malaria parasite field samples. Here, we have genotyped STRs using HipSTR in more than 3,000 Plasmodium falciparum and 174 Plasmodium vivax published whole-genome sequence data from samples collected across the globe. High levels of noise and variability in the resultant callset necessitated the development of a novel method for quality control of STR genotype calls. A set of high-quality STR loci (6,768 from P. falciparum and 3,496 from P. vivax) were used to study Plasmodium genetic diversity, population structures and genomic signatures of selection and these were compared to genome-wide single nucleotide polymorphism (SNP) genotyping data. In addition, the genome-wide information about genetic variation and other characteristics of STRs in P. falciparum and P. vivax have been available in an interactive web-based R Shiny application PlasmoSTR (https://github.com/bahlolab/PlasmoSTR).
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Affiliation(s)
- Jiru Han
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
| | - Jacob E. Munro
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
| | - Anthony Kocoski
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Mathematics and Statistics, The University of Melbourne, Melbourne, Australia
| | - Alyssa E. Barry
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
- Disease Elimination Program, Burnet Institute, Melbourne, Australia
- IMPACT Institute for Innovation in Mental and Physical Health and Clinical Translation, Deakin University, Geelong, Australia
| | - Melanie Bahlo
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
- * E-mail:
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12
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Abstract
The human malaria parasite Plasmodium vivax commonly causes complex multiclonal infections. Recently, Dia et al. have developed innovative methods for single-cell sequencing (SCS) of P. vivax infections by adapting an approach used previously for Plasmodium falciparum. Their studies provide fascinating new insights into P. vivax intrahost diversity and evolution.
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Affiliation(s)
- Alyssa E Barry
- Institute of Mental and Physical Health and Clinical Translation (IMPACT) and School of Medicine, Deakin University, Geelong, Victoria, Australia; Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia.
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13
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Mkuu RS, Gilreath TD, Barry AE, Nafukho FM, Rahman J, Chowdhury MAB, Wekullo C, Harvey IS. Identifying individuals with multiple non-communicable disease risk factors in Kenya: a latent class analysis. Public Health 2021; 198:180-186. [PMID: 34461453 DOI: 10.1016/j.puhe.2021.07.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 06/16/2021] [Accepted: 07/26/2021] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Non-communicable diseases (NCDs) are the leading causes of death globally. In Kenya, the number of deaths resulting from NCDs is projected to surpass malaria and tuberculosis by 2030. Studies in Kenya show increasing NCDs; the aim of the present study is to examine the clustering of NCDs and risk factors in Kenya. STUDY DESIGN This is a cross-sectional study using data from the 2015 Kenya STEPwise Survey. METHODS This study examined relationships between NCDs (e.g. obesity, hypertension and diabetes) and health behaviours (e.g. sedentary activity, and fruit and vegetable consumption). Survey probability weights, which estimated the sampling design effect, were applied to consider the sampling units, and stratifications were used during sampling so that the results could be generalisable to the national adult Kenyan population. In total, 4350 adults were included in the study sample. RESULTS Overall, 24.43% of participants were classified as having hypertension, 1.88% as having type 2 diabetes, and 27.94% were classified as being overweight or obese. The best-fit model was a four-class solution. Class 1 is best described as 'young with high NCD risk' and had the highest sedentary activity. Class 2 is best described as 'poor rural with lower NCD risk' with a high chance of smoking and alcohol consumption. Class 3 is best described as 'rural with high NCD risk' and had the highest fruit and vegetable consumption. Class 4 is best described as 'wealthy young urban dwellers with high NCD risk' with a high chance of alcohol consumption and smoking. Individuals in Class 4 had the highest chance (40%) of being overweight/obese, a 2% chance of type 2 diabetes and a 23% chance of having hypertension. CONCLUSIONS NCDs are clustered in groups with high-risk behaviours. The group with the highest chance of having NCDs also had the highest chance of engaging in high-risk behaviours. The findings of this study suggest that smoking and alcohol consumption increase NCD risk in rural areas. Tailored and targeted interventions are needed to curb the increasing NCD prevalence in Kenya.
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Affiliation(s)
- R S Mkuu
- University of Florida, College of Medicine, Gainesville, FL, USA.
| | - T D Gilreath
- Texas A&M University, Transdisciplinary Center for Health Equity Research, College Station, TX, USA.
| | - A E Barry
- Texas A&M University, Department of Health and Kinesiology, College Station, TX, USA.
| | - F M Nafukho
- Texas A&M University, College of Education and Human Development, College Station, TX, USA.
| | - J Rahman
- BRAC University, Dhaka, Bangladesh.
| | - M A B Chowdhury
- University of Florida, College of Medicine, Gainesville, FL, USA.
| | - C Wekullo
- Masinde Muliro University of Science and Technology, Kakamega, Kenya.
| | - I S Harvey
- Texas A&M University, Department of Health and Kinesiology, College Station, TX, USA.
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14
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Ahouidi A, Ali M, Almagro-Garcia J, Amambua-Ngwa A, Amaratunga C, Amato R, Amenga-Etego L, Andagalu B, Anderson TJC, Andrianaranjaka V, Apinjoh T, Ariani C, Ashley EA, Auburn S, Awandare GA, Ba H, Baraka V, Barry AE, Bejon P, Bertin GI, Boni MF, Borrmann S, Bousema T, Branch O, Bull PC, Busby GBJ, Chookajorn T, Chotivanich K, Claessens A, Conway D, Craig A, D'Alessandro U, Dama S, Day NPJ, Denis B, Diakite M, Djimdé A, Dolecek C, Dondorp AM, Drakeley C, Drury E, Duffy P, Echeverry DF, Egwang TG, Erko B, Fairhurst RM, Faiz A, Fanello CA, Fukuda MM, Gamboa D, Ghansah A, Golassa L, Goncalves S, Hamilton WL, Harrison GLA, Hart L, Henrichs C, Hien TT, Hill CA, Hodgson A, Hubbart C, Imwong M, Ishengoma DS, Jackson SA, Jacob CG, Jeffery B, Jeffreys AE, Johnson KJ, Jyothi D, Kamaliddin C, Kamau E, Kekre M, Kluczynski K, Kochakarn T, Konaté A, Kwiatkowski DP, Kyaw MP, Lim P, Lon C, Loua KM, Maïga-Ascofaré O, Malangone C, Manske M, Marfurt J, Marsh K, Mayxay M, Miles A, Miotto O, Mobegi V, Mokuolu OA, Montgomery J, Mueller I, Newton PN, Nguyen T, Nguyen TN, Noedl H, Nosten F, Noviyanti R, Nzila A, Ochola-Oyier LI, Ocholla H, Oduro A, Omedo I, Onyamboko MA, Ouedraogo JB, Oyebola K, Pearson RD, Peshu N, Phyo AP, Plowe CV, Price RN, Pukrittayakamee S, Randrianarivelojosia M, Rayner JC, Ringwald P, Rockett KA, Rowlands K, Ruiz L, Saunders D, Shayo A, Siba P, Simpson VJ, Stalker J, Su XZ, Sutherland C, Takala-Harrison S, Tavul L, Thathy V, Tshefu A, Verra F, Vinetz J, Wellems TE, Wendler J, White NJ, Wright I, Yavo W, Ye H. An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples. Wellcome Open Res 2021; 6:42. [PMID: 33824913 PMCID: PMC8008441 DOI: 10.12688/wellcomeopenres.16168.1] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/15/2021] [Indexed: 02/02/2023] Open
Abstract
MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.
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Affiliation(s)
| | | | - Mozam Ali
- Wellcome Sanger Institute, Hinxton, UK
| | - Jacob Almagro-Garcia
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Alfred Amambua-Ngwa
- Wellcome Sanger Institute, Hinxton, UK,Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Chanaki Amaratunga
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Roberto Amato
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Lucas Amenga-Etego
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana,West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana
| | - Ben Andagalu
- United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | | | | | | | | | - Elizabeth A Ashley
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Sarah Auburn
- Menzies School of Health Research, Darwin, Australia,Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Gordon A. Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana,University of Ghana, Legon, Ghana
| | - Hampate Ba
- Institut National de Recherche en Santé Publique, Nouakchott, Mauritania
| | - Vito Baraka
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,Department of Epidemiology, International Health Unit, University of Antwerp, Antwerp, Belgium
| | - Alyssa E. Barry
- Deakin University, Geelong, Australia,Burnet Institute, Melbourne, Australia,Walter and Eliza Hall Institute, Melbourne, Australia
| | - Philip Bejon
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Maciej F. Boni
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Steffen Borrmann
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Teun Bousema
- London School of Hygiene and Tropical Medicine, London, UK,Radboud University Medical Center, Nijmegen, The Netherlands
| | - Oralee Branch
- NYU School of Medicine Langone Medical Center, New York, USA
| | - Peter C. Bull
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Pathology, University of Cambridge, Cambridge, UK
| | - George B. J. Busby
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Antoine Claessens
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia,LPHI, MIVEGEC, INSERM, CNRS, IRD, University of Montpellier, Montpellier, France
| | - David Conway
- London School of Hygiene and Tropical Medicine, London, UK
| | - Alister Craig
- Liverpool School of Tropical Medicine, Liverpool, UK,Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Umberto D'Alessandro
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Souleymane Dama
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Nicholas PJ Day
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Brigitte Denis
- Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Mahamadou Diakite
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Abdoulaye Djimdé
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Chris Drakeley
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - Patrick Duffy
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Diego F. Echeverry
- Centro Internacional de Entrenamiento e Investigaciones Médicas - CIDEIM, Cali, Colombia,Universidad Icesi, Cali, Colombia
| | | | - Berhanu Erko
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | | | | | - Mark M. Fukuda
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Dionicia Gamboa
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Anita Ghansah
- Nogouchi Memorial Institute for Medical Research, Legon-Accra, Ghana
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | - William L. Hamilton
- Wellcome Sanger Institute, Hinxton, UK,Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | | | - Lee Hart
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Christa Henrichs
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Tran Tinh Hien
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | | | - Christina Hubbart
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Deus S. Ishengoma
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,East African Consortium for Clinical Research (EACCR), Dar es Salaam, Tanzania
| | - Scott A. Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA, USA
| | | | - Ben Jeffery
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Anna E. Jeffreys
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Kimberly J. Johnson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Edwin Kamau
- Walter Reed Army Institute of Research, U.S. Military HIV Research Program, Silver Spring, MD, USA
| | | | - Krzysztof Kluczynski
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Theerarat Kochakarn
- Wellcome Sanger Institute, Hinxton, UK,Mahidol University, Bangkok, Thailand
| | | | - Dominic P. Kwiatkowski
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Myat Phone Kyaw
- The Myanmar Oxford Clinical Research Unit, University of Oxford, Yangon, Myanmar,University of Public Health, Yangon, Myanmar
| | - Pharath Lim
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA,Medical Care Development International, Maryland, USA
| | - Chanthap Lon
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | | | - Oumou Maïga-Ascofaré
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,Research in Tropical Medicine, Kwame Nkrumah University of Sciences and Technology, Kumasi, Ghana
| | | | | | - Jutta Marfurt
- Menzies School of Health Research, Darwin, Australia
| | - Kevin Marsh
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,African Academy of Sciences, Nairobi, Kenya
| | - Mayfong Mayxay
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Vientiane, Lao People's Democratic Republic,Institute of Research and Education Development (IRED), University of Health Sciences, Ministry of Health, Vientiane, Lao People's Democratic Republic
| | - Alistair Miles
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Victor Mobegi
- School of Medicine, University of Nairobi, Nairobi, Kenya
| | - Olugbenga A. Mokuolu
- Department of Paediatrics and Child Health, University of Ilorin, Ilorin, Nigeria
| | - Jacqui Montgomery
- Institute of Vector-Borne Disease, Monash University, Clayton, Victoria, 3800, Australia
| | - Ivo Mueller
- Walter and Eliza Hall Institute, Melbourne, Australia,Barcelona Centre for International Health Research, Barcelona, Spain
| | - Paul N. Newton
- Wellcome Trust-Mahosot Hospital-Oxford Tropical Medicine Research Collaboration, Vientiane, Lao People's Democratic Republic
| | | | - Thuy-Nhien Nguyen
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Harald Noedl
- MARIB - Malaria Research Initiative Bandarban, Bandarban, Bangladesh
| | - Francois Nosten
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Shoklo Malaria Research Unit, Bangkok, Thailand
| | | | - Alexis Nzila
- King Fahid University of Petroleum and Minerals (KFUMP), Dharhran, Saudi Arabia
| | | | - Harold Ocholla
- KEMRI - Centres for Disease Control and Prevention (CDC) Research Program, Kisumu, Kenya,Centre for Bioinformatics and Biotechnology, University of Nairobi, Nairobi, Kenya
| | - Abraham Oduro
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | - Irene Omedo
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Marie A. Onyamboko
- Kinshasa School of Public Health, University of Kinshasa, Kinshasa, Congo, Democratic Republic
| | | | - Kolapo Oyebola
- Nigerian Institute of Medical Research, Lagos, Nigeria,Parasitology and Bioinformatics Unit, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Richard D. Pearson
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Norbert Peshu
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Aung Pyae Phyo
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Shoklo Malaria Research Unit, Bangkok, Thailand
| | - Chris V. Plowe
- School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Ric N. Price
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Menzies School of Health Research, Darwin, Australia,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | - Milijaona Randrianarivelojosia
- Institut Pasteur de Madagascar, Antananarivo, Madagascar,Universités d'Antananarivo et de Mahajanga, Antananarivo, Madagascar
| | | | | | - Kirk A. Rockett
- Wellcome Sanger Institute, Hinxton, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Lastenia Ruiz
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | - David Saunders
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Alex Shayo
- Nelson Mandela Institute of Science and Technology, Arusha, Tanzania
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Victoria J. Simpson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | - Xin-zhuan Su
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | | | - Shannon Takala-Harrison
- Center for Vaccine Development and Global Health, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Livingstone Tavul
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Vandana Thathy
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York, USA
| | | | | | - Joseph Vinetz
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru,Yale School of Medicine, New Haven, CT, USA
| | - Thomas E. Wellems
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Jason Wendler
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Nicholas J. White
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Ian Wright
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - William Yavo
- University Félix Houphouët-Boigny, Abidjan, Cote d'Ivoire,Malaria Research and Control Center of the National Institute of Public Health, Abidjan, Cote d'Ivoire
| | - Htut Ye
- Department of Medical Research, Yangon, Myanmar
| |
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15
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Ahouidi A, Ali M, Almagro-Garcia J, Amambua-Ngwa A, Amaratunga C, Amato R, Amenga-Etego L, Andagalu B, Anderson TJC, Andrianaranjaka V, Apinjoh T, Ariani C, Ashley EA, Auburn S, Awandare GA, Ba H, Baraka V, Barry AE, Bejon P, Bertin GI, Boni MF, Borrmann S, Bousema T, Branch O, Bull PC, Busby GBJ, Chookajorn T, Chotivanich K, Claessens A, Conway D, Craig A, D'Alessandro U, Dama S, Day NPJ, Denis B, Diakite M, Djimdé A, Dolecek C, Dondorp AM, Drakeley C, Drury E, Duffy P, Echeverry DF, Egwang TG, Erko B, Fairhurst RM, Faiz A, Fanello CA, Fukuda MM, Gamboa D, Ghansah A, Golassa L, Goncalves S, Hamilton WL, Harrison GLA, Hart L, Henrichs C, Hien TT, Hill CA, Hodgson A, Hubbart C, Imwong M, Ishengoma DS, Jackson SA, Jacob CG, Jeffery B, Jeffreys AE, Johnson KJ, Jyothi D, Kamaliddin C, Kamau E, Kekre M, Kluczynski K, Kochakarn T, Konaté A, Kwiatkowski DP, Kyaw MP, Lim P, Lon C, Loua KM, Maïga-Ascofaré O, Malangone C, Manske M, Marfurt J, Marsh K, Mayxay M, Miles A, Miotto O, Mobegi V, Mokuolu OA, Montgomery J, Mueller I, Newton PN, Nguyen T, Nguyen TN, Noedl H, Nosten F, Noviyanti R, Nzila A, Ochola-Oyier LI, Ocholla H, Oduro A, Omedo I, Onyamboko MA, Ouedraogo JB, Oyebola K, Pearson RD, Peshu N, Phyo AP, Plowe CV, Price RN, Pukrittayakamee S, Randrianarivelojosia M, Rayner JC, Ringwald P, Rockett KA, Rowlands K, Ruiz L, Saunders D, Shayo A, Siba P, Simpson VJ, Stalker J, Su XZ, Sutherland C, Takala-Harrison S, Tavul L, Thathy V, Tshefu A, Verra F, Vinetz J, Wellems TE, Wendler J, White NJ, Wright I, Yavo W, Ye H. An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples. Wellcome Open Res 2021; 6:42. [PMID: 33824913 PMCID: PMC8008441.2 DOI: 10.12688/wellcomeopenres.16168.2] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/28/2021] [Indexed: 02/02/2023] Open
Abstract
MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.
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Affiliation(s)
| | | | - Mozam Ali
- Wellcome Sanger Institute, Hinxton, UK
| | - Jacob Almagro-Garcia
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Alfred Amambua-Ngwa
- Wellcome Sanger Institute, Hinxton, UK,Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Chanaki Amaratunga
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Roberto Amato
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Lucas Amenga-Etego
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana,West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana
| | - Ben Andagalu
- United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | | | | | | | | | - Elizabeth A Ashley
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Sarah Auburn
- Menzies School of Health Research, Darwin, Australia,Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Gordon A. Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana,University of Ghana, Legon, Ghana
| | - Hampate Ba
- Institut National de Recherche en Santé Publique, Nouakchott, Mauritania
| | - Vito Baraka
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,Department of Epidemiology, International Health Unit, University of Antwerp, Antwerp, Belgium
| | - Alyssa E. Barry
- Deakin University, Geelong, Australia,Burnet Institute, Melbourne, Australia,Walter and Eliza Hall Institute, Melbourne, Australia
| | - Philip Bejon
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Maciej F. Boni
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Steffen Borrmann
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Teun Bousema
- London School of Hygiene and Tropical Medicine, London, UK,Radboud University Medical Center, Nijmegen, The Netherlands
| | - Oralee Branch
- NYU School of Medicine Langone Medical Center, New York, USA
| | - Peter C. Bull
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Pathology, University of Cambridge, Cambridge, UK
| | - George B. J. Busby
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Antoine Claessens
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia,LPHI, MIVEGEC, INSERM, CNRS, IRD, University of Montpellier, Montpellier, France
| | - David Conway
- London School of Hygiene and Tropical Medicine, London, UK
| | - Alister Craig
- Liverpool School of Tropical Medicine, Liverpool, UK,Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Umberto D'Alessandro
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Souleymane Dama
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Nicholas PJ Day
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Brigitte Denis
- Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Mahamadou Diakite
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Abdoulaye Djimdé
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Chris Drakeley
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - Patrick Duffy
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Diego F. Echeverry
- Centro Internacional de Entrenamiento e Investigaciones Médicas - CIDEIM, Cali, Colombia,Universidad Icesi, Cali, Colombia
| | | | - Berhanu Erko
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | | | | | - Mark M. Fukuda
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Dionicia Gamboa
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Anita Ghansah
- Nogouchi Memorial Institute for Medical Research, Legon-Accra, Ghana
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | - William L. Hamilton
- Wellcome Sanger Institute, Hinxton, UK,Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | | | - Lee Hart
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Christa Henrichs
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Tran Tinh Hien
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | | | - Christina Hubbart
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Deus S. Ishengoma
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,East African Consortium for Clinical Research (EACCR), Dar es Salaam, Tanzania
| | - Scott A. Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA, USA
| | | | - Ben Jeffery
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Anna E. Jeffreys
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Kimberly J. Johnson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Edwin Kamau
- Walter Reed Army Institute of Research, U.S. Military HIV Research Program, Silver Spring, MD, USA
| | | | - Krzysztof Kluczynski
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Theerarat Kochakarn
- Wellcome Sanger Institute, Hinxton, UK,Mahidol University, Bangkok, Thailand
| | | | - Dominic P. Kwiatkowski
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Myat Phone Kyaw
- The Myanmar Oxford Clinical Research Unit, University of Oxford, Yangon, Myanmar,University of Public Health, Yangon, Myanmar
| | - Pharath Lim
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA,Medical Care Development International, Maryland, USA
| | - Chanthap Lon
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | | | - Oumou Maïga-Ascofaré
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,Research in Tropical Medicine, Kwame Nkrumah University of Sciences and Technology, Kumasi, Ghana
| | | | | | - Jutta Marfurt
- Menzies School of Health Research, Darwin, Australia
| | - Kevin Marsh
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,African Academy of Sciences, Nairobi, Kenya
| | - Mayfong Mayxay
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Vientiane, Lao People's Democratic Republic,Institute of Research and Education Development (IRED), University of Health Sciences, Ministry of Health, Vientiane, Lao People's Democratic Republic
| | - Alistair Miles
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Victor Mobegi
- School of Medicine, University of Nairobi, Nairobi, Kenya
| | - Olugbenga A. Mokuolu
- Department of Paediatrics and Child Health, University of Ilorin, Ilorin, Nigeria
| | - Jacqui Montgomery
- Institute of Vector-Borne Disease, Monash University, Clayton, Victoria, 3800, Australia
| | - Ivo Mueller
- Walter and Eliza Hall Institute, Melbourne, Australia,Barcelona Centre for International Health Research, Barcelona, Spain
| | - Paul N. Newton
- Wellcome Trust-Mahosot Hospital-Oxford Tropical Medicine Research Collaboration, Vientiane, Lao People's Democratic Republic
| | | | - Thuy-Nhien Nguyen
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Harald Noedl
- MARIB - Malaria Research Initiative Bandarban, Bandarban, Bangladesh
| | - Francois Nosten
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Shoklo Malaria Research Unit, Bangkok, Thailand
| | | | - Alexis Nzila
- King Fahid University of Petroleum and Minerals (KFUMP), Dharhran, Saudi Arabia
| | | | - Harold Ocholla
- KEMRI - Centres for Disease Control and Prevention (CDC) Research Program, Kisumu, Kenya,Centre for Bioinformatics and Biotechnology, University of Nairobi, Nairobi, Kenya
| | - Abraham Oduro
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | - Irene Omedo
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Marie A. Onyamboko
- Kinshasa School of Public Health, University of Kinshasa, Kinshasa, Congo, Democratic Republic
| | | | - Kolapo Oyebola
- Nigerian Institute of Medical Research, Lagos, Nigeria,Parasitology and Bioinformatics Unit, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Richard D. Pearson
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Norbert Peshu
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Aung Pyae Phyo
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Shoklo Malaria Research Unit, Bangkok, Thailand
| | - Chris V. Plowe
- School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Ric N. Price
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Menzies School of Health Research, Darwin, Australia,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | - Milijaona Randrianarivelojosia
- Institut Pasteur de Madagascar, Antananarivo, Madagascar,Universités d'Antananarivo et de Mahajanga, Antananarivo, Madagascar
| | | | | | - Kirk A. Rockett
- Wellcome Sanger Institute, Hinxton, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Lastenia Ruiz
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | - David Saunders
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Alex Shayo
- Nelson Mandela Institute of Science and Technology, Arusha, Tanzania
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Victoria J. Simpson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | - Xin-zhuan Su
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | | | - Shannon Takala-Harrison
- Center for Vaccine Development and Global Health, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Livingstone Tavul
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Vandana Thathy
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York, USA
| | | | | | - Joseph Vinetz
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru,Yale School of Medicine, New Haven, CT, USA
| | - Thomas E. Wellems
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Jason Wendler
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Nicholas J. White
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Ian Wright
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - William Yavo
- University Félix Houphouët-Boigny, Abidjan, Cote d'Ivoire,Malaria Research and Control Center of the National Institute of Public Health, Abidjan, Cote d'Ivoire
| | - Htut Ye
- Department of Medical Research, Yangon, Myanmar
| |
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16
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Lautu-Gumal D, Razook Z, Koleala T, Nate E, McEwen S, Timbi D, Hetzel MW, Lavu E, Tefuarani N, Makita L, Kazura J, Mueller I, Pomat W, Laman M, Robinson LJ, Barry AE. Surveillance of molecular markers of Plasmodium falciparum artemisinin resistance (kelch13 mutations) in Papua New Guinea between 2016 and 2018. Int J Parasitol Drugs Drug Resist 2021; 16:188-193. [PMID: 34271323 PMCID: PMC8286961 DOI: 10.1016/j.ijpddr.2021.06.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/22/2021] [Accepted: 06/25/2021] [Indexed: 11/28/2022]
Abstract
Plasmodium falciparum resistance to artemisinin-based combination therapy (ACT) is a global threat to malaria control and elimination efforts. Mutations in the P. falciparum kelch13 gene (Pfk13) that are associated with delayed parasite clearance have emerged on the Thai-Cambodian border since 2008. There is growing evidence of widespread Pfk13 mutations throughout South-East Asia and they have independently emerged in other endemic regions. In Papua New Guinea (PNG), Pfk13 “C580Y” mutant parasites with reduced in vitro sensitivity to artemisinin have been isolated in Wewak, a port town in East Sepik Province. However, the extent of any local spread of these mutant parasites in other parts of PNG is unknown. We investigated the prevalence of Pfk13 mutations in multiple malaria-endemic regions of PNG. P. falciparum isolates (n = 1152) collected between 2016 and 2018 and assessed for Pfk13 variation by sequencing. Of 663 high quality Pfk13 sequences a total of five variants were identified. They included C580Y, a mutation at a previously documented polymorphic locus: N499K, and three previously undescribed mutations: R471C, K586E and Y635C. All variants were found in single isolates, indicating that these Pfk13 mutations were rare in the areas surveyed. Notably, C580Y was absent from Maprik district, which neighbours Wewak where C580Y mutant parasites were previously identified. The single C580Y isolate was found in the port town of Lae, Morobe Province, a potential entry site for the importation of drug resistant parasites into PNG. Although sample size in this location was small (n = 5), our identification of a C580Y mutant in this second location is concerning, highlighting the urgent need for further surveillance in Lae. Other Pfk13 mutants were rare in PNG between 2016 and 2018. Continued surveillance for molecular markers of drug resistance is critically important to inform malaria control in PNG.
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Affiliation(s)
- Dulcie Lautu-Gumal
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia; Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea; Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia.
| | - Zahra Razook
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; Institute for Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Tamarah Koleala
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Elma Nate
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Samuel McEwen
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia
| | - Diana Timbi
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Manuel W Hetzel
- Health Interventions Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Evelyn Lavu
- Papua New Guinea Central Public Health Laboratories, Port Moresby, National Capital District, Papua New Guinea
| | - Nakapi Tefuarani
- School of Medicine & Health Sciences, University of Papua New Guinea, Port Moresby, National Capital District, Papua New Guinea
| | - Leo Makita
- Papua New Guinea National Department of Health, Port Moresby, National Capital District, Papua New Guinea
| | - James Kazura
- Centre for Global Health Diseases, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia; Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - William Pomat
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Moses Laman
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Leanne J Robinson
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia; Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea; Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; School of Preventative Medicine and Public Health, Monash University, Melbourne, Victoria, Australia
| | - Alyssa E Barry
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia; Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; Institute for Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Geelong, Victoria, Australia
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17
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O'Flaherty K, Oo WH, Zaloumis SG, Cutts JC, Aung KZ, Thein MM, Drew DR, Razook Z, Barry AE, Parischa N, Zaw NN, Thu HK, Thi A, Htay WYM, Soe AP, Simpson JA, Beeson JG, Agius PA, Fowkes FJI. Community-based molecular and serological surveillance of subclinical malaria in Myanmar. BMC Med 2021; 19:121. [PMID: 34044836 PMCID: PMC8161608 DOI: 10.1186/s12916-021-01993-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 04/27/2021] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND In the Greater Mekong Subregion (GMS), current malaria surveillance strategies rely on a network of village health volunteers (VHVs) reporting the results of rapid diagnostic tests (RDTs), known to miss many asymptomatic infections. Integration of more sensitive diagnostic molecular and serological measures into the VHV network may improve surveillance of residual malaria transmission in hard-to-reach areas in the region and inform targeted interventions and elimination responses. However, data on residual malaria transmission that would be captured by these measures in the VHV-led testing and treatment surveillance network in the GMS is unknown. METHODS A total of 114 VHVs were trained to collect dried blood spots from villagers undergoing routine RDTs as part of VHV-led active and passive case detection from April 2015 to June 2016. Samples were subjected to molecular testing (quantitative polymerase chain reaction [qPCR]) to determine Plasmodium falciparum and P. vivax infection and serological testing (against P. falciparum and P. vivax antigens) to determine exposure to P. falciparum and P. vivax. RESULTS Over 15 months, 114 VHVs performed 32,194 RDTs and collected samples for molecular (n = 13,157) and serological (n = 14,128) testing. The prevalence of molecular-detectable P. falciparum and P. vivax infection was 3.2% compared to the 0.16% prevalence of Plasmodium spp. by RDT, highlighting the large burden of infections undetected by standard surveillance. Peaks in anti-P. falciparum, but not P. vivax, merozoite IgG seroprevalence coincided with seasonal P. falciparum transmission peaks, even in those with no molecularly detectable parasites. At the individual level, antibody seropositivity was associated with reduced odds of contemporaneous P. falciparum (OR for PfCSP 0.51 [95%CI 0.35, 0.76], p = 0.001, PfAMA1 0.70 [95%CI 0.52, 0.93], p = 0.01, and PfMSP2 0.81 [95%CI 0.61, 1.08], p = 0.15), but not P. vivax infection (OR PvAMA1 1.02 [95%CI 0.73, 1.43], p = 0.89) indicating a potential role of immunity in protection against molecular-detectable P. falciparum parasitaemia. CONCLUSIONS We demonstrated that integration and implementation of sample collection for molecular and serological surveillance into networks of VHV servicing hard-to-reach populations in the GMS is feasible, can capture significant levels of ongoing undetected seasonal malaria transmission and has the potential to supplement current routine RDT testing. Improving malaria surveillance by advancing the integration of molecular and serological techniques, through centralised testing approaches or novel point-of-contact tests, will advance progress, and tracking, towards malaria elimination goals in the GMS.
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Affiliation(s)
- Katherine O'Flaherty
- Burnet Institute for Medical Research and Public Health, Melbourne, Australia.,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Win Han Oo
- Burnet Institute Myanmar, Yangon, Myanmar
| | - Sophie G Zaloumis
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Julia C Cutts
- Burnet Institute for Medical Research and Public Health, Melbourne, Australia.,Department of Medicine, University of Melbourne, Melbourne, Australia
| | | | | | - Damien R Drew
- Burnet Institute for Medical Research and Public Health, Melbourne, Australia
| | - Zahra Razook
- School of Medicine, Deakin University, Geelong, Australia
| | - Alyssa E Barry
- Burnet Institute for Medical Research and Public Health, Melbourne, Australia.,Department of Medicine, University of Melbourne, Melbourne, Australia.,School of Medicine, Deakin University, Geelong, Australia
| | - Naanki Parischa
- Burnet Institute for Medical Research and Public Health, Melbourne, Australia
| | | | | | - Aung Thi
- Department of Public Health, Myanmar Ministry of Health, Nay Pyi Taw, Myanmar
| | | | | | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - James G Beeson
- Burnet Institute for Medical Research and Public Health, Melbourne, Australia.,Department of Medicine, University of Melbourne, Melbourne, Australia.,Department of Microbiology and Central Clinical School, Monash University, Melbourne, Australia
| | - Paul A Agius
- Burnet Institute for Medical Research and Public Health, Melbourne, Australia.,Department of Epidemiology and Preventative Medicine, Monash University, Melbourne, Australia.,Judith Lumley Centre, La Trobe University, Melbourne, Australia
| | - Freya J I Fowkes
- Burnet Institute for Medical Research and Public Health, Melbourne, Australia. .,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia. .,Department of Epidemiology and Preventative Medicine, Monash University, Melbourne, Australia. .,Department of Infectious Diseases, Monash University, Melbourne, Australia.
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18
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Shah Z, Naung MT, Moser KA, Adams M, Buchwald AG, Dwivedi A, Ouattara A, Seydel KB, Mathanga DP, Barry AE, Serre D, Laufer MK, Silva JC, Takala-Harrison S. Whole-genome analysis of Malawian Plasmodium falciparum isolates identifies possible targets of allele-specific immunity to clinical malaria. PLoS Genet 2021; 17:e1009576. [PMID: 34033654 PMCID: PMC8184011 DOI: 10.1371/journal.pgen.1009576] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 06/07/2021] [Accepted: 05/04/2021] [Indexed: 12/30/2022] Open
Abstract
Individuals acquire immunity to clinical malaria after repeated Plasmodium falciparum infections. Immunity to disease is thought to reflect the acquisition of a repertoire of responses to multiple alleles in diverse parasite antigens. In previous studies, we identified polymorphic sites within individual antigens that are associated with parasite immune evasion by examining antigen allele dynamics in individuals followed longitudinally. Here we expand this approach by analyzing genome-wide polymorphisms using whole genome sequence data from 140 parasite isolates representing malaria cases from a longitudinal study in Malawi and identify 25 genes that encode possible targets of naturally acquired immunity that should be validated immunologically and further characterized for their potential as vaccine candidates.
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Affiliation(s)
- Zalak Shah
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Myo T. Naung
- Population Health and Immunity Division, Walter Eliza Hall of Medical Institute for Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Carlton, Victoria, Australia
- School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Kara A. Moser
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Matthew Adams
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Andrea G. Buchwald
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Ankit Dwivedi
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Amed Ouattara
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Karl B. Seydel
- Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, United States of America
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Don P. Mathanga
- University of Malawi College of Medicine, Malaria Alert Centre, Blantyre, Malawi
| | - Alyssa E. Barry
- Population Health and Immunity Division, Walter Eliza Hall of Medical Institute for Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Carlton, Victoria, Australia
- School of Medicine, Deakin University, Geelong, Victoria, Australia
- Disease Elimination and Maternal and Child Health, Burnet Institute, Melbourne, Victoria, Australia
| | - David Serre
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Miriam K. Laufer
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Joana C. Silva
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Shannon Takala-Harrison
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
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19
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Miotto O, Sekihara M, Tachibana SI, Yamauchi M, Pearson RD, Amato R, Gonçalves S, Mehra S, Noviyanti R, Marfurt J, Auburn S, Price RN, Mueller I, Ikeda M, Mori T, Hirai M, Tavul L, Hetzel MW, Laman M, Barry AE, Ringwald P, Ohashi J, Hombhanje F, Kwiatkowski DP, Mita T. Emergence of artemisinin-resistant Plasmodium falciparum with kelch13 C580Y mutations on the island of New Guinea. PLoS Pathog 2020; 16:e1009133. [PMID: 33320907 PMCID: PMC7771869 DOI: 10.1371/journal.ppat.1009133] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 12/29/2020] [Accepted: 11/05/2020] [Indexed: 12/22/2022] Open
Abstract
The rapid and aggressive spread of artemisinin-resistant Plasmodium falciparum carrying the C580Y mutation in the kelch13 gene is a growing threat to malaria elimination in Southeast Asia, but there is no evidence of their spread to other regions. We conducted cross-sectional surveys in 2016 and 2017 at two clinics in Wewak, Papua New Guinea (PNG) where we identified three infections caused by C580Y mutants among 239 genotyped clinical samples. One of these mutants exhibited the highest survival rate (6.8%) among all parasites surveyed in ring-stage survival assays (RSA) for artemisinin. Analyses of kelch13 flanking regions, and comparisons of deep sequencing data from 389 clinical samples from PNG, Indonesian Papua and Western Cambodia, suggested an independent origin of the Wewak C580Y mutation, showing that the mutants possess several distinctive genetic features. Identity by descent (IBD) showed that multiple portions of the mutants' genomes share a common origin with parasites found in Indonesian Papua, comprising several mutations within genes previously associated with drug resistance, such as mdr1, ferredoxin, atg18 and pnp. These findings suggest that a P. falciparum lineage circulating on the island of New Guinea has gradually acquired a complex ensemble of variants, including kelch13 C580Y, which have affected the parasites' drug sensitivity. This worrying development reinforces the need for increased surveillance of the evolving parasite populations on the island, to contain the spread of resistance.
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Affiliation(s)
- Olivo Miotto
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, United Kingdom
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Wellcome Sanger Institute, Hinxton, United Kingdom
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Makoto Sekihara
- Department of Tropical Medicine and Parasitology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Shin-Ichiro Tachibana
- Department of Tropical Medicine and Parasitology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Masato Yamauchi
- Department of Tropical Medicine and Parasitology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Richard D. Pearson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, United Kingdom
- Wellcome Sanger Institute, Hinxton, United Kingdom
| | | | | | - Somya Mehra
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | | | - Jutta Marfurt
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | - Sarah Auburn
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | - Ric N. Price
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | - Ivo Mueller
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Mie Ikeda
- Department of Tropical Medicine and Parasitology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Toshiyuki Mori
- Department of Tropical Medicine and Parasitology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Makoto Hirai
- Department of Tropical Medicine and Parasitology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Livingstone Tavul
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Manuel W. Hetzel
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Moses Laman
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Alyssa E. Barry
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- University of Melbourne, Melbourne, Australia
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Deakin University, Geelong, Australia
- Burnet Institute, Melbourne, Australia
| | | | - Jun Ohashi
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan
| | - Francis Hombhanje
- Centre for Health Research & Diagnostics, Divine Word University, Madang, Papua New Guinea
| | - Dominic P. Kwiatkowski
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, United Kingdom
- Wellcome Sanger Institute, Hinxton, United Kingdom
| | - Toshihiro Mita
- Department of Tropical Medicine and Parasitology, Juntendo University Faculty of Medicine, Tokyo, Japan
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20
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Kattenberg JH, Razook Z, Keo R, Koepfli C, Jennison C, Lautu-Gumal D, Fola AA, Ome-Kaius M, Barnadas C, Siba P, Felger I, Kazura J, Mueller I, Robinson LJ, Barry AE. Monitoring Plasmodium falciparum and Plasmodium vivax using microsatellite markers indicates limited changes in population structure after substantial transmission decline in Papua New Guinea. Mol Ecol 2020; 29:4525-4541. [PMID: 32985031 PMCID: PMC10008436 DOI: 10.1111/mec.15654] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 07/27/2020] [Indexed: 02/01/2023]
Abstract
Monitoring the genetic structure of pathogen populations may be an economical and sensitive approach to quantify the impact of control on transmission dynamics, highlighting the need for a better understanding of changes in population genetic parameters as transmission declines. Here we describe the first population genetic analysis of two major human malaria parasites, Plasmodium falciparum (Pf) and Plasmodium vivax (Pv), following nationwide distribution of long-lasting insecticide-treated nets (LLINs) in Papua New Guinea (PNG). Parasite isolates from pre- (2005-2006) and post-LLIN (2010-2014) were genotyped using microsatellite markers. Despite parasite prevalence declining substantially (East Sepik Province: Pf = 54.9%-8.5%, Pv = 35.7%-5.6%, Madang Province: Pf = 38.0%-9.0%, Pv: 31.8%-19.7%), genetically diverse and intermixing parasite populations remained. Pf diversity declined modestly post-LLIN relative to pre-LLIN (East Sepik: Rs = 7.1-6.4, HE = 0.77-0.71; Madang: Rs = 8.2-6.1, HE = 0.79-0.71). Unexpectedly, population structure present in pre-LLIN populations was lost post-LLIN, suggesting that more frequent human movement between provinces may have contributed to higher gene flow. Pv prevalence initially declined but increased again in one province, yet diversity remained high throughout the study period (East Sepik: Rs = 11.4-9.3, HE = 0.83-0.80; Madang: Rs = 12.2-14.5, HE = 0.85-0.88). Although genetic differentiation values increased between provinces over time, no significant population structure was observed at any time point. For both species, a decline in multiple infections and increasing clonal transmission and significant multilocus linkage disequilibrium post-LLIN were positive indicators of impact on the parasite population using microsatellite markers. These parameters may be useful adjuncts to traditional epidemiological tools in the early stages of transmission reduction.
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Affiliation(s)
- Johanna Helena Kattenberg
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Yagaum, Papua New Guinea
| | - Zahra Razook
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
| | - Raksmei Keo
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
| | - Cristian Koepfli
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Charlie Jennison
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Dulcie Lautu-Gumal
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Yagaum, Papua New Guinea.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Abebe A Fola
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Maria Ome-Kaius
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Yagaum, Papua New Guinea.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Céline Barnadas
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Yagaum, Papua New Guinea.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Ingrid Felger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - James Kazura
- Centre for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia.,Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Leanne J Robinson
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Yagaum, Papua New Guinea.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia.,Disease Elimination, Burnet Institute, Melbourne, VIC, Australia
| | - Alyssa E Barry
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
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21
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Fola AA, Kattenberg E, Razook Z, Lautu-Gumal D, Lee S, Mehra S, Bahlo M, Kazura J, Robinson LJ, Laman M, Mueller I, Barry AE. SNP barcodes provide higher resolution than microsatellite markers to measure Plasmodium vivax population genetics. Malar J 2020; 19:375. [PMID: 33081815 PMCID: PMC7576724 DOI: 10.1186/s12936-020-03440-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 10/03/2020] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Genomic surveillance of malaria parasite populations has the potential to inform control strategies and to monitor the impact of interventions. Barcodes comprising large numbers of single nucleotide polymorphism (SNP) markers are accurate and efficient genotyping tools, however may need to be tailored to specific malaria transmission settings, since 'universal' barcodes can lack resolution at the local scale. A SNP barcode was developed that captures the diversity and structure of Plasmodium vivax populations of Papua New Guinea (PNG) for research and surveillance. METHODS Using 20 high-quality P. vivax genome sequences from PNG, a total of 178 evenly spaced neutral SNPs were selected for development of an amplicon sequencing assay combining a series of multiplex PCRs and sequencing on the Illumina MiSeq platform. For initial testing, 20 SNPs were amplified in a small number of mono- and polyclonal P. vivax infections. The full barcode was then validated by genotyping and population genetic analyses of 94 P. vivax isolates collected between 2012 and 2014 from four distinct catchment areas on the highly endemic north coast of PNG. Diversity and population structure determined from the SNP barcode data was then benchmarked against that of ten microsatellite markers used in previous population genetics studies. RESULTS From a total of 28,934,460 reads generated from the MiSeq Illumina run, 87% mapped to the PvSalI reference genome with deep coverage (median = 563, range 56-7586) per locus across genotyped samples. Of 178 SNPs assayed, 146 produced high-quality genotypes (minimum coverage = 56X) in more than 85% of P. vivax isolates. No amplification bias was introduced due to either polyclonal infection or whole genome amplification (WGA) of samples before genotyping. Compared to the microsatellite panels, the SNP barcode revealed greater variability in genetic diversity between populations and geographical population structure. The SNP barcode also enabled assignment of genotypes according to their geographic origins with a significant association between genetic distance and geographic distance at the sub-provincial level. CONCLUSIONS High-throughput SNP barcoding can be used to map variation of malaria transmission dynamics at sub-national resolution. The low cost per sample and genotyping strategy makes the transfer of this technology to field settings highly feasible.
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Affiliation(s)
- Abebe A Fola
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, USA
| | - Eline Kattenberg
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
- Malariology Unit, Institute of Tropical Medicine, Antwerp, Belgium
| | - Zahra Razook
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- IMPACT Institute for Innovation in Mental and Physical Health and Clinical Translation, Deakin University, 75 Pigdons Road, Waurn Ponds, Geelong, VIC, 3216, Australia
| | - Dulcie Lautu-Gumal
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
- Disease Elimination Program, Burnet Institute, Melbourne, VIC, Australia
- IMPACT Institute for Innovation in Mental and Physical Health and Clinical Translation, Deakin University, 75 Pigdons Road, Waurn Ponds, Geelong, VIC, 3216, Australia
| | - Stuart Lee
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
| | - Somya Mehra
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- Disease Elimination Program, Burnet Institute, Melbourne, VIC, Australia
- IMPACT Institute for Innovation in Mental and Physical Health and Clinical Translation, Deakin University, 75 Pigdons Road, Waurn Ponds, Geelong, VIC, 3216, Australia
| | - Melanie Bahlo
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia
| | - James Kazura
- Disease Elimination Program, Burnet Institute, Melbourne, VIC, Australia
- Centre for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio, USA
| | - Leanne J Robinson
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
- Disease Elimination Program, Burnet Institute, Melbourne, VIC, Australia
| | - Moses Laman
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Ivo Mueller
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia
- Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Alyssa E Barry
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.
- Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia.
- Disease Elimination Program, Burnet Institute, Melbourne, VIC, Australia.
- IMPACT Institute for Innovation in Mental and Physical Health and Clinical Translation, Deakin University, 75 Pigdons Road, Waurn Ponds, Geelong, VIC, 3216, Australia.
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22
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Agius PA, Cutts JC, Han Oo W, Thi A, O'Flaherty K, Zayar Aung K, Kyaw Thu H, Poe Aung P, Mon Thein M, Nyi Zaw N, Yan Min Htay W, Paing Soe A, Razook Z, Barry AE, Htike W, Devine A, Simpson JA, Crabb BS, Beeson JG, Pasricha N, Fowkes FJI. Evaluation of the effectiveness of topical repellent distributed by village health volunteer networks against Plasmodium spp. infection in Myanmar: A stepped-wedge cluster randomised trial. PLoS Med 2020; 17:e1003177. [PMID: 32817632 PMCID: PMC7444540 DOI: 10.1371/journal.pmed.1003177] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 07/29/2020] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND The World Health Organization has yet to endorse deployment of topical repellents for malaria prevention as part of public health campaigns. We aimed to quantify the effectiveness of repellent distributed by the village health volunteer (VHV) network in the Greater Mekong Subregion (GMS) in reducing malaria in order to advance regional malaria elimination. METHODS AND FINDINGS Between April 2015 and June 2016, a 15-month stepped-wedge cluster randomised trial was conducted in 116 villages in Myanmar (stepped monthly in blocks) to test the effectiveness of 12% N,N-diethylbenzamide w/w cream distributed by VHVs, on Plasmodium spp. infection. The median age of participants was 18 years, approximately half were female, and the majority were either village residents (46%) or forest dwellers (40%). No adverse events were reported during the study. Generalised linear mixed modelling estimated the effect of repellent on infection detected by rapid diagnostic test (RDT) (primary outcome) and polymerase chain reaction (PCR) (secondary outcome). Overall Plasmodium infection detected by RDT was low (0.16%; 50/32,194), but infection detected by PCR was higher (3%; 419/13,157). There was no significant protection against RDT-detectable infection (adjusted odds ratio [AOR] = 0.25, 95% CI 0.004-15.2, p = 0.512). In Plasmodium-species-specific analyses, repellent protected against PCR-detectable P. falciparum (adjusted relative risk ratio [ARRR] = 0.67, 95% CI 0.47-0.95, p = 0.026), but not P. vivax infection (ARRR = 1.41, 95% CI 0.80-2.47, p = 0.233). Repellent effects were similar when delayed effects were modelled, across risk groups, and regardless of village-level and temporal heterogeneity in malaria prevalence. The incremental cost-effectiveness ratio was US$256 per PCR-detectable infection averted. Study limitations were a lower than expected Plasmodium spp. infection rate and potential geographic dilution of the intervention. CONCLUSIONS In this study, we observed apparent protection against new infections associated with the large-scale distribution of repellent by VHVs. Incorporation of repellent into national strategies, particularly in areas where bed nets are less effective, may contribute to the interruption of malaria transmission. Further studies are warranted across different transmission settings and populations, from the GMS and beyond, to inform WHO public health policy on the deployment of topical repellents for malaria prevention. TRIAL REGISTRATION Australian and New Zealand Clinical Trials Registry (ACTRN12616001434482).
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Affiliation(s)
- Paul A Agius
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar.,Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
| | - Julia C Cutts
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar
| | - Win Han Oo
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar
| | - Aung Thi
- Department of Public Health, Myanmar Ministry of Health and Sports, Nay Pyi Taw, Myanmar
| | - Katherine O'Flaherty
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar.,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Victoria, Australia
| | | | - Htin Kyaw Thu
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar
| | - Poe Poe Aung
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar
| | - Myat Mon Thein
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar
| | - Nyi Nyi Zaw
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar
| | | | - Aung Paing Soe
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar
| | - Zahra Razook
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
| | - Alyssa E Barry
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar.,Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.,Global Health Division, Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Win Htike
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar
| | - Angela Devine
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Victoria, Australia.,Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia
| | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Victoria, Australia
| | | | - James G Beeson
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar.,Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia.,Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | | | - Freya J I Fowkes
- Burnet Institute, Victoria, Australia, and Yangon, Myanmar.,Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Victoria, Australia
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23
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Kattenberg JH, Gumal DL, Ome-Kaius M, Kiniboro B, Philip M, Jally S, Kasian B, Sambale N, Siba PM, Karl S, Barry AE, Felger I, Kazura JW, Mueller I, Robinson LJ. The epidemiology of Plasmodium falciparum and Plasmodium vivax in East Sepik Province, Papua New Guinea, pre- and post-implementation of national malaria control efforts. Malar J 2020; 19:198. [PMID: 32503607 PMCID: PMC7275396 DOI: 10.1186/s12936-020-03265-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 05/20/2020] [Indexed: 02/07/2023] Open
Abstract
Background In the past decade, national malaria control efforts in Papua New Guinea (PNG) have received renewed support, facilitating nationwide distribution of free long-lasting insecticidal nets (LLINs), as well as improvements in access to parasite-confirmed diagnosis and effective artemisinin-combination therapy in 2011–2012. Methods To study the effects of these intensified control efforts on the epidemiology and transmission of Plasmodium falciparum and Plasmodium vivax infections and investigate risk factors at the individual and household level, two cross-sectional surveys were conducted in the East Sepik Province of PNG; one in 2005, before the scale-up of national campaigns and one in late 2012-early 2013, after 2 rounds of LLIN distribution (2008 and 2011–2012). Differences between studies were investigated using Chi square (χ2), Fischer’s exact tests and Student’s t-test. Multivariable logistic regression models were built to investigate factors associated with infection at the individual and household level. Results The prevalence of P. falciparum and P. vivax in surveyed communities decreased from 55% (2005) to 9% (2013) and 36% to 6%, respectively. The mean multiplicity of infection (MOI) decreased from 1.8 to 1.6 for P. falciparum (p = 0.08) and from 2.2 to 1.4 for P. vivax (p < 0.001). Alongside these reductions, a shift towards a more uniform distribution of infections and illness across age groups was observed but there was greater heterogeneity across the study area and within the study villages. Microscopy positive infections and clinical cases in the household were associated with high rate infection households (> 50% of household members with Plasmodium infection). Conclusion After the scale-up of malaria control interventions in PNG between 2008 and 2012, there was a substantial reduction in P. falciparum and P. vivax infection rates in the studies villages in East Sepik Province. Understanding the extent of local heterogeneity in malaria transmission and the driving factors is critical to identify and implement targeted control strategies to ensure the ongoing success of malaria control in PNG and inform the development of tools required to achieve elimination. In household-based interventions, diagnostics with a sensitivity similar to (expert) microscopy could be used to identify and target high rate households.
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Affiliation(s)
- Johanna H Kattenberg
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea.,Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia.,Department of Biomedical Sciences, Institute of Tropical Medicine, Malariology Unit, Nationalestraat 155, 2000, Antwerp, Belgium
| | - Dulcie L Gumal
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea.,Disease Elimination Program, Vector-borne Diseases and Tropical Public Health Group, Burnet Institute, 85 Commercial Rd, Melbourne, VIC, 3004, Australia
| | - Maria Ome-Kaius
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea.,Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia
| | - Benson Kiniboro
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Matthew Philip
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Shadrach Jally
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Bernadine Kasian
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Naomi Sambale
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Peter M Siba
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Stephan Karl
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea.,Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia
| | - Alyssa E Barry
- Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3010, Australia.,School of Medicine, Deakin University, Geelong and Burnet Institute, Melbourne, VIC, Australia
| | - Ingrid Felger
- Medical Parasitology and Infection Biology, Swiss Tropical & Public Health Institute, Socinstrasse 57, 4051, Basel, Switzerland
| | - James W Kazura
- Center for Global Health and Diseases, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH, 44106, USA
| | - Ivo Mueller
- Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3010, Australia.,Department of Parasites and Insect Vectors, Malaria Parasites and Hosts Unit, Pasteur Institute, 25-28 rue du Docteur-Roux, 75724, Paris Cedex 15, France
| | - Leanne J Robinson
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea. .,Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3010, Australia. .,Disease Elimination Program, Vector-borne Diseases and Tropical Public Health Group, Burnet Institute, 85 Commercial Rd, Melbourne, VIC, 3004, Australia.
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24
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Olusanya OO, Wigfall LT, Rossheim ME, Tomar A, Barry AE. Binge drinking, HIV/HPV co-infection risk, and HIV testing: Factors associated with HPV vaccination among young adults in the United States. Prev Med 2020; 134:106023. [PMID: 32061685 PMCID: PMC7195993 DOI: 10.1016/j.ypmed.2020.106023] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 01/12/2020] [Accepted: 02/10/2020] [Indexed: 12/30/2022]
Abstract
Human papillomavirus (HPV) is a common sexually transmitted infection. Binge drinkers often engage in HIV/HPV co-infection high-risk behaviors. We examined the association between binge drinking, HIV/HPV co-infection risk, HIV testing and HPV vaccination among young adults. Data from the 2017 Behavioral Risk Factor Surveillance System survey were examined. Participants (N = 430/450,016; 0.11%) were HPV vaccine-eligible young adults ages 18-26 years. Multivariable logistic regression examined the association between binge drinking in the past 30 days, HIV/HPV co-infection high-risk risk behaviors, HIV testing, and HPV vaccination (initiated/completed, unvaccinated) among young adults. Respondents were primarily cisgender (99.8%), non-Hispanic White (41.4%), employed (46.2%) or student (35.4%), and insured (68.2%). Most did not binge drink (55.2%). The majority did not engage in HIV/HPV co-infection high-risk risk behaviors (78.2%). More than one-half had never been tested for HIV (59%) nor vaccinated against HPV (60.6%). Although binge drinkers (44.8%) were significantly more likely to engage in HIV/HPV co-infection high-risk behaviors (OR = 2.1; 95% CI: 1.0-4.5), binge drinking was not positively associated with HIV testing (OR = 0.98; 95% CI: 0.63-1.53). After adjusting for demographics and HIV/HPV co-infection high-risk behaviors, one (aOR = 2.71; 95% CI: 1.11-6.65) and two episodes (aOR = 3.05; 95% CI: 1.26-7.41) of binge drinking in the past 30 days were significantly associated with HPV vaccination uptake. Positive associations between HPV vaccination and participants having an HIV test in 2017 (aOR = 3.86; 95% CI: 1.42-10.55) and before 2017 (aOR = 2.62; 95% CI: 1.23-5.56) were also statistically significant. Because young adult binge drinkers are more likely to engage in HIV/HPV co-infection high-risk behaviors, promoting HPV vaccination and HIV testing are important public health objectives.
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Affiliation(s)
- O O Olusanya
- Department of Biology, Texas A&M University, Butler Hall, 3258, 525 Lubbock Street, College Station, TX 77843, United States of America.
| | - L T Wigfall
- Texas A&M University, College of Education and Human Development, Department of Health and Kinesiology, Division of Health Education, United States of America.
| | - M E Rossheim
- Department of Global and Community Health, George Mason University, 4400 University Drive, MS5B7, Peterson Family Health Sciences Hall, Fairfax, VA 22030, United States of America.
| | - A Tomar
- Texas A&M University, College of Education and Human Development, Department of Health and Kinesiology, Division of Health Education, United States of America.
| | - A E Barry
- Texas A&M University, College of Education and Human Development, Department of Health and Kinesiology, Division of Health Education, United States of America.
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25
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Tessema SK, Nakajima R, Jasinskas A, Monk SL, Lekieffre L, Lin E, Kiniboro B, Proietti C, Siba P, Felgner PL, Doolan DL, Mueller I, Barry AE. Protective Immunity against Severe Malaria in Children Is Associated with a Limited Repertoire of Antibodies to Conserved PfEMP1 Variants. Cell Host Microbe 2020; 26:579-590.e5. [PMID: 31726028 DOI: 10.1016/j.chom.2019.10.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 08/08/2019] [Accepted: 10/18/2019] [Indexed: 01/31/2023]
Abstract
Extreme diversity of the major Plasmodium falciparum antigen, PfEMP1, poses a barrier to identifying targets of immunity to malaria. Here, we used protein microarrays containing hundreds of variants of the DBLα domain of PfEMP1 to cover the diversity of Papua New Guinean (PNG) parasites. Probing the plasma of a longitudinal cohort of malaria-exposed PNG children showed that group 2 DBLα antibodies were moderately associated with a lower risk of uncomplicated malaria, whereas individual variants were only weakly associated with clinical immunity. In contrast, antibodies to 85 individual group 1 and 2 DBLα variants were associated with a 70%-100% reduction in severe malaria. Of these, 17 variants were strong predictors of severe malaria. Analysis of full-length PfEMP1 sequences from PNG samples shows that these 17 variants are linked to pathogenic CIDR domains. This suggests that whereas immunity to uncomplicated malaria requires a broad repertoire of antibodies, immunity to severe malaria targets a subset of conserved variants. These findings provide insights into antimalarial immunity and potential antibody biomarkers for disease risk.
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Affiliation(s)
- Sofonias K Tessema
- Division of Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Melbourne 3052, VIC, Australia; Department of Medical Biology, University of Melbourne, Melbourne 3000, VIC, Australia
| | - Rie Nakajima
- Physiology & Biophysics Department, Vaccine R&D Center, University of California, Irvine, Irvine 92697, CA, USA
| | - Algis Jasinskas
- Physiology & Biophysics Department, Vaccine R&D Center, University of California, Irvine, Irvine 92697, CA, USA
| | - Stephanie L Monk
- Division of Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Melbourne 3052, VIC, Australia; Department of Medical Biology, University of Melbourne, Melbourne 3000, VIC, Australia
| | - Lea Lekieffre
- Infectious Diseases Programme, QIMR Berghofer Medical Research Institute, Brisbane 4006, QLD, Australia
| | - Enmoore Lin
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka 441, EHG, Papua New Guinea
| | - Benson Kiniboro
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka 441, EHG, Papua New Guinea
| | - Carla Proietti
- Infectious Diseases Programme, QIMR Berghofer Medical Research Institute, Brisbane 4006, QLD, Australia; Australian Institute of Tropical Health and Medicine, James Cook University, Cairns 4878, QLD, Australia
| | - Peter Siba
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka 441, EHG, Papua New Guinea
| | - Philip L Felgner
- Physiology & Biophysics Department, Vaccine R&D Center, University of California, Irvine, Irvine 92697, CA, USA
| | - Denise L Doolan
- Infectious Diseases Programme, QIMR Berghofer Medical Research Institute, Brisbane 4006, QLD, Australia; Australian Institute of Tropical Health and Medicine, James Cook University, Cairns 4878, QLD, Australia
| | - Ivo Mueller
- Division of Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Melbourne 3052, VIC, Australia; Department of Medical Biology, University of Melbourne, Melbourne 3000, VIC, Australia; Department of Parasites and Insect Vectors, Institut Pasteur, Paris 75015, France
| | - Alyssa E Barry
- Division of Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Melbourne 3052, VIC, Australia; Department of Medical Biology, University of Melbourne, Melbourne 3000, VIC, Australia.
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26
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Mitjà O, Godornes C, Houinei W, Kapa A, Paru R, Abel H, González-Beiras C, Bieb SV, Wangi J, Barry AE, Sanz S, Bassat Q, Lukehart SA. Re-emergence of yaws after single mass azithromycin treatment followed by targeted treatment: a longitudinal study. Lancet 2018; 391:1599-1607. [PMID: 29428183 PMCID: PMC5920722 DOI: 10.1016/s0140-6736(18)30204-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 08/29/2017] [Accepted: 11/23/2017] [Indexed: 11/25/2022]
Abstract
BACKGROUND Yaws is a substantial cause of chronic disfiguring ulcers in children in at least 14 countries in the tropics. WHO's newly adopted strategy for yaws eradication uses a single round of mass azithromycin treatment followed by targeted treatment programmes, and data from pilot studies have shown a short-term significant reduction of yaws. We assessed the long-term efficacy of the WHO strategy for yaws eradication. METHODS Between April 15, 2013, and Oct 24, 2016, we did a longitudinal study on a Papua New Guinea island (Lihir; 16 092 population) in which yaws was endemic. In the initial study, the participants were followed for 12 months; in this extended follow-up study, clinical, serological, and PCR surveys were continued every 6 months for 42 months. We used genotyping and travel history to identify importation events. Active yaws confirmed by PCR specific for Treponema pallidum was the primary outcome indicator. The study is registered with ClinicalTrials.gov, number NCT01955252. FINDINGS Mass azithromycin treatment (coverage rate of 84%) followed by targeted treatment programmes reduced the prevalence of active yaws from 1·8% to a minimum of 0·1% at 18 months (difference from baseline -1·7%, 95% CI, -1·9 to -1·4; p<0·0001), but the infection began to re-emerge after 24 months with a significant increase to 0·4% at 42 months (difference from 18 months 0·3%, 95% CI 0·1 to 0·4; p<0·0001). At each timepoint after baseline, more than 70% of the total community burden of yaws was found in individuals who had not had the mass treatment or as new infections in non-travelling residents. At months 36 and 42, five cases of active yaws, all from the same village, showed clinical failure following azithromycin treatment, with PCR-detected mutations in the 23S ribosomal RNA genes conferring resistance to azithromycin. A sustained decrease in the prevalence of high-titre latent yaws from 13·7% to <1·5% in asymptomatic children aged 1-5 years old and of genetic diversity of yaws strains from 0·139 to less than 0·046 between months 24 and 42 indicated a reduction in transmission of infection. INTERPRETATION The implementation of the WHO strategy did not, in the long-term, achieve elimination in a high-endemic community mainly due to the individuals who were absent at the time of mass treatment in whom yaws reactivated; repeated mass treatment might be necessary to eliminate yaws. To our knowledge, this is the first report of the emergence of azithromycin-resistant T p pertenue and spread within one village. Communities' surveillance should be strengthened to detect any possible treatment failure and biological markers of resistance. FUNDING ISDIN laboratories, Newcrest Mining Limited, and US Public Health Service National Institutes of Health.
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Affiliation(s)
- Oriol Mitjà
- Barcelona Institute for Global Health, Hospital Clinic-University of Barcelona, Barcelona, Spain; Division of Public Health, School of Medicine and Health Sciences, University of Papua New Guinea, Port Moresby, Papua New Guinea; Lihir Medical Center, International SOS-Newcrest Mining, Lihir Island, Papua New Guinea.
| | - Charmie Godornes
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - Wendy Houinei
- Disease Control Branch, National Department of Health, Port Moresby, Papua New Guinea
| | - August Kapa
- Lihir Medical Center, International SOS-Newcrest Mining, Lihir Island, Papua New Guinea
| | - Raymond Paru
- Lihir Medical Center, International SOS-Newcrest Mining, Lihir Island, Papua New Guinea
| | - Haina Abel
- Lihir Medical Center, International SOS-Newcrest Mining, Lihir Island, Papua New Guinea
| | - Camila González-Beiras
- Barcelona Institute for Global Health, Hospital Clinic-University of Barcelona, Barcelona, Spain; Lisbon Institute of Hygiene and Tropical Medicine, Lisbon, Portugal
| | - Sibauk V Bieb
- Disease Control Branch, National Department of Health, Port Moresby, Papua New Guinea
| | - James Wangi
- Office of the World Health Organization (WHO) Representative for Papua New Guinea, WHO, Port Moresby, Papua New Guinea
| | - Alyssa E Barry
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Sergi Sanz
- Barcelona Institute for Global Health, Hospital Clinic-University of Barcelona, Barcelona, Spain; Biostatistics Unit, Department of Public Health, Faculty of Medicine, University of Barcelona, Barcelona, Spain
| | - Quique Bassat
- Barcelona Institute for Global Health, Hospital Clinic-University of Barcelona, Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain; Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique; Paediatric Infectious Diseases Unit, Paediatric Department, Hospital Sant Joan de Déu, Barcelona, Spain
| | - Sheila A Lukehart
- Department of Medicine, University of Washington, Seattle, WA, USA; Department of Global Health, University of Washington, Seattle, WA, USA
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27
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Koepfli C, Ome-Kaius M, Jally S, Malau E, Maripal S, Ginny J, Timinao L, Kattenberg JH, Obadia T, White M, Rarau P, Senn N, Barry AE, Kazura JW, Mueller I, Robinson LJ. Sustained Malaria Control Over an 8-Year Period in Papua New Guinea: The Challenge of Low-Density Asymptomatic Plasmodium Infections. J Infect Dis 2017; 216:1434-1443. [PMID: 29029179 PMCID: PMC5853328 DOI: 10.1093/infdis/jix507] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 09/19/2017] [Indexed: 12/31/2022] Open
Abstract
Background The scale-up of effective malaria control in the last decade has resulted in a substantial decline in the incidence of clinical malaria in many countries. The effects on the proportions of asymptomatic and submicroscopic infections and on transmission potential are yet poorly understood. Methods In Papua New Guinea, vector control has been intensified since 2008, and improved diagnosis and treatment was introduced in 2012. Cross-sectional surveys were conducted in Madang Province in 2006 (with 1280 survey participants), 2010 (with 2117 participants), and 2014 (with 2516 participants). Infections were quantified by highly sensitive quantitative polymerase chain reaction (PCR) analysis, and gametocytes were quantified by reverse-transcription qPCR analysis. Results Plasmodium falciparum prevalence determined by qPCR decreased from 42% in 2006 to 9% in 2014. The P. vivax prevalence decreased from 42% in 2006 to 13% in 2010 but then increased to 20% in 2014. Parasite densities decreased 5-fold from 2006 to 2010; 72% of P. falciparum and 87% of P. vivax infections were submicroscopic in 2014. Gametocyte density and positivity correlated closely with parasitemia, and population gametocyte prevalence decreased 3-fold for P. falciparum and 29% for P. vivax from 2010 to 2014. Conclusions Sustained control has resulted in reduced malaria transmission potential, but an increasing proportion of gametocyte carriers are asymptomatic and submicroscopic and represent a challenge to malaria control.
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Affiliation(s)
- Cristian Koepfli
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- University of California–Irvine
| | - Maria Ome-Kaius
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- Papua New Guinea Institute of Medical Research, Madang
| | | | - Elisheba Malau
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
| | | | - Jason Ginny
- Papua New Guinea Institute of Medical Research, Madang
| | | | - Johanna Helena Kattenberg
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Papua New Guinea Institute of Medical Research, Madang
| | - Thomas Obadia
- Malaria: Parasites & Hosts Unit, Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
- Bioinformatics and Biostatistics Hub, Center for Bioinformatics, Biostatistics, and Integrative Biology, Institut Pasteur, Paris, France
| | - Michael White
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, United Kingdom
| | - Patricia Rarau
- School of Population and Global Health, University of Melbourne, Parkville, Australia
- Papua New Guinea Institute of Medical Research, Madang
| | - Nicolas Senn
- Papua New Guinea Institute of Medical Research, Madang
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Alyssa E Barry
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
| | | | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- Malaria: Parasites & Hosts Unit, Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
- Barcelona Center for International Health, Barcelona, Spain
| | - Leanne J Robinson
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- Burnet Institute, Melbourne, Australia
- Papua New Guinea Institute of Medical Research, Madang
- Correspondence: L. Robinson, PhD, MPH, Walter and Eliza Hall Institute, 1G Royal Parade, Parkville VIC 3052, Australia ()
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Godornes C, Giacani L, Barry AE, Mitja O, Lukehart SA. Development of a Multilocus Sequence Typing (MLST) scheme for Treponema pallidum subsp. pertenue: Application to yaws in Lihir Island, Papua New Guinea. PLoS Negl Trop Dis 2017; 11:e0006113. [PMID: 29281641 PMCID: PMC5760108 DOI: 10.1371/journal.pntd.0006113] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 01/09/2018] [Accepted: 11/14/2017] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Yaws is a neglected tropical disease, caused by Treponema pallidum subsp. pertenue. The disease causes chronic lesions, primarily in young children living in remote villages in tropical climates. As part of a global yaws eradication campaign initiated by the World Health Organization, we sought to develop and evaluate a molecular typing method to distinguish different strains of T. pallidum subsp. pertenue for disease control and epidemiological purposes. METHODS AND PRINCIPAL FINDINGS Published genome sequences of strains of T. pallidum subsp. pertenue and pallidum were compared to identify polymorphic genetic loci among the strains. DNA from a number of existing historical Treponema isolates, as well as a subset of samples from yaws patients collected in Lihir Island, Papua New Guinea, were analyzed using these targets. From these data, three genes (tp0548, tp0136 and tp0326) were ultimately selected to give a high discriminating capability among the T. pallidum subsp. pertenue samples tested. Intragenic regions of these three target genes were then selected to enhance the discriminating capability of the typing scheme using short readily amplifiable loci. This 3-gene multilocus sequence typing (MLST) method was applied to existing historical human yaws strains, the Fribourg-Blanc simian isolate, and DNA from 194 lesion swabs from yaws patients on Lihir Island, Papua New Guinea. Among all samples tested, fourteen molecular types were identified, seven of which were found in patient samples and seven among historical isolates or DNA. Three types (JG8, TD6, and SE7) were predominant on Lihir Island. CONCLUSIONS This MLST approach allows molecular typing and differentiation of yaws strains. This method could be a useful tool to complement epidemiological studies in regions where T. pallidum subsp. pertenue is prevalent with the overall goals of improving our understanding of yaws transmission dynamics and helping the yaws eradication campaign to succeed.
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Affiliation(s)
- Charmie Godornes
- Department of Medicine, University of Washington, Seattle, Washington, United States of America
| | - Lorenzo Giacani
- Department of Medicine, University of Washington, Seattle, Washington, United States of America
- Department of Global Health, University of Washington, Seattle, Washington, United States of America
| | - Alyssa E. Barry
- Division of Population Health and Immunity, Walter and Eliza Hall Institute, Parkville, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
| | - Oriol Mitja
- Barcelona Institute for Global Health, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
- Division of Public Health, School of Medicine and Health Sciences, University of Papua New Guinea, Port Moresby, Papua New Guinea
- Lihir Medical Center, International SOS-Newcrest Mining, Lihir Island, Papua New Guinea
| | - Sheila A. Lukehart
- Department of Medicine, University of Washington, Seattle, Washington, United States of America
- Department of Global Health, University of Washington, Seattle, Washington, United States of America
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29
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Fola AA, Harrison GLA, Hazairin MH, Barnadas C, Hetzel MW, Iga J, Siba PM, Mueller I, Barry AE. Higher Complexity of Infection and Genetic Diversity of Plasmodium vivax Than Plasmodium falciparum Across All Malaria Transmission Zones of Papua New Guinea. Am J Trop Med Hyg 2017; 96:630-641. [PMID: 28070005 DOI: 10.4269/ajtmh.16-0716] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Plasmodium falciparum and Plasmodium vivax have varying transmission dynamics that are informed by molecular epidemiology. This study aimed to determine the complexity of infection and genetic diversity of P. vivax and P. falciparum throughout Papua New Guinea (PNG) to evaluate transmission dynamics across the country. In 2008-2009, a nationwide malaria indicator survey collected 8,936 samples from all 16 endemic provinces of PNG. Of these, 892 positive P. vivax samples were genotyped at PvMS16 and PvmspF3, and 758 positive P. falciparum samples were genotyped at Pfmsp2. The data were analyzed for multiplicity of infection (MOI) and genetic diversity. Overall, P. vivax had higher polyclonality (71%) and mean MOI (2.32) than P. falciparum (20%, 1.39). These measures were significantly associated with prevalence for P. falciparum but not for P. vivax. The genetic diversity of P. vivax (PvMS16: expected heterozygosity = 0.95, 0.85-0.98; PvMsp1F3: 0.78, 0.66-0.89) was higher and less variable than that of P. falciparum (Pfmsp2: 0.89, 0.65-0.97). Significant associations of MOI with allelic richness (rho = 0.69, P = 0.009) and expected heterozygosity (rho = 0.87, P < 0.001) were observed for P. falciparum. Conversely, genetic diversity was not correlated with polyclonality nor mean MOI for P. vivax. The results demonstrate higher complexity of infection and genetic diversity of P. vivax across the country. Although P. falciparum shows a strong association of these parameters with prevalence, a lack of association was observed for P. vivax and is consistent with higher potential for outcrossing of this species.
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Affiliation(s)
- Abebe A Fola
- Department of Medical Biology, University of Melbourne, Parkville, Australia.,Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - G L Abby Harrison
- Department of Medical Biology, University of Melbourne, Parkville, Australia.,Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Mita Hapsari Hazairin
- Department of Epidemiology and Preventative Medicine, Monash University, Clayton, Australia.,Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Céline Barnadas
- Statens Serum Institut, Copenhagen, Denmark.,European Public Health Microbiology (EUPHEM) Training Programme, European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden.,Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Manuel W Hetzel
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Jonah Iga
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Peter M Siba
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Ivo Mueller
- Institut Pasteur, Paris, France.,Department of Medical Biology, University of Melbourne, Parkville, Australia.,Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Alyssa E Barry
- Department of Medical Biology, University of Melbourne, Parkville, Australia.,Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
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30
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Auburn S, Barry AE. Dissecting malaria biology and epidemiology using population genetics and genomics. Int J Parasitol 2016; 47:77-85. [PMID: 27825828 DOI: 10.1016/j.ijpara.2016.08.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 08/09/2016] [Accepted: 08/25/2016] [Indexed: 10/20/2022]
Abstract
Molecular approaches have an increasingly recognized utility in surveillance of malaria parasite populations, not only in defining prevalence and incidence with higher sensitivity than traditional methods, but also in monitoring local and regional parasite transmission patterns. In this review, we provide an overview of population genetic and genomic studies of human-infecting Plasmodium species, highlighting recent advances in the field. In accordance with the renewed impetus for malaria eradication, many studies are now using genetic and genomic epidemiology to support local evidence-based intervention strategies. Microsatellite genotyping remains a popular approach for both Plasmodium falciparum and Plasmodium vivax. However, with the increasing availability of whole genome sequencing data enabling effective single nucleotide polymorphism-based panels tailored to a given study question and setting, this approach is gaining popularity. The availability of new reference genomes for Plasmodium malariae and Plasmodium ovale should see a surge in similar molecular studies on these currently neglected species. Genomic studies are revealing new insights into important adaptive mechanisms of the parasite including antimalarial drug resistance. The advent of new methodologies such as selective whole genome amplification for dealing with extensive human DNA in low density field isolates should see genome-wide approaches becoming routine for parasite surveillance once the economic costs outweigh the current cost benefits of targeted approaches.
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Affiliation(s)
- Sarah Auburn
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Australia
| | - Alyssa E Barry
- Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; Department of Medical Biology, University of Melbourne, Melbourne, Australia.
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31
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Karl S, White MT, Milne GJ, Gurarie D, Hay SI, Barry AE, Felger I, Mueller I. Spatial Effects on the Multiplicity of Plasmodium falciparum Infections. PLoS One 2016; 11:e0164054. [PMID: 27711149 PMCID: PMC5053403 DOI: 10.1371/journal.pone.0164054] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/19/2016] [Indexed: 11/18/2022] Open
Abstract
As malaria is being pushed back on many frontiers and global case numbers are declining, accurate measurement and prediction of transmission becomes increasingly difficult. Low transmission settings are characterised by high levels of spatial heterogeneity, which stands in stark contrast to the widely used assumption of spatially homogeneous transmission used in mathematical transmission models for malaria. In the present study an individual-based mathematical malaria transmission model that incorporates multiple parasite clones, variable human exposure and duration of infection, limited mosquito flight distance and most importantly geographically heterogeneous human and mosquito population densities was used to illustrate the differences between homogeneous and heterogeneous transmission assumptions when aiming to predict surrogate indicators of transmission intensity such as population parasite prevalence or multiplicity of infection (MOI). In traditionally highly malaria endemic regions where most of the population harbours malaria parasites, humans are often infected with multiple parasite clones. However, studies have shown also in areas with low overall parasite prevalence, infection with multiple parasite clones is a common occurrence. Mathematical models assuming homogeneous transmission between humans and mosquitoes cannot explain these observations. Heterogeneity of transmission can arise from many factors including acquired immunity, body size and occupational exposure. In this study, we show that spatial heterogeneity has a profound effect on predictions of MOI and parasite prevalence. We illustrate, that models assuming homogeneous transmission underestimate average MOI in low transmission settings when compared to field data and that spatially heterogeneous models predict stable transmission at much lower overall parasite prevalence. Therefore it is very important that models used to guide malaria surveillance and control strategies in low transmission and elimination settings take into account the spatial features of the specific target area, including human and mosquito vector distribution.
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Affiliation(s)
- Stephan Karl
- Population-Based Biology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
- Vector-borne Diseases Unit, Papua New Guinea Insititute of Medical Research, Madang, Madang Province, Papua New Guinea
- * E-mail:
| | - Michael T. White
- Population-Based Biology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- MRC Centre for Outbreak Analysis & Modelling, Department of Infectious Disease Epidemiology, Imperial College, London, United Kingdom
| | - George J. Milne
- School of Computer Science and Software Engineering, The University of Western Australia, Perth, WA, Australia
| | - David Gurarie
- Department of Mathematics, Applied Mathematics and Statistics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Simon I. Hay
- Institute for Health Metrics and Evaluation, Seattle, Washington, United States of America
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Alyssa E. Barry
- Population-Based Biology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Ingrid Felger
- Department of Medical Parasitology and Infection Biology Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Ivo Mueller
- Population-Based Biology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
- Malaria: Parasites and Hosts Unit, Department of Parasites & Insect Vectors, Institut Pasteur, Paris, France
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Escalante AA, Ferreira MU, Vinetz JM, Volkman SK, Cui L, Gamboa D, Krogstad DJ, Barry AE, Carlton JM, van Eijk AM, Pradhan K, Mueller I, Greenhouse B, Andreina Pacheco M, Vallejo AF, Herrera S, Felger I. Malaria Molecular Epidemiology: Lessons from the International Centers of Excellence for Malaria Research Network. Am J Trop Med Hyg 2015; 93:79-86. [PMID: 26259945 PMCID: PMC4574277 DOI: 10.4269/ajtmh.15-0005] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 05/15/2015] [Indexed: 01/31/2023] Open
Abstract
Molecular epidemiology leverages genetic information to study the risk factors that affect the frequency and distribution of malaria cases. This article describes molecular epidemiologic investigations currently being carried out by the International Centers of Excellence for Malaria Research (ICEMR) network in a variety of malaria-endemic settings. First, we discuss various novel approaches to understand malaria incidence and gametocytemia, focusing on Plasmodium falciparum and Plasmodium vivax. Second, we describe and compare different parasite genotyping methods commonly used in malaria epidemiology and population genetics. Finally, we discuss potential applications of molecular epidemiological tools and methods toward malaria control and elimination efforts.
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Affiliation(s)
- Ananias A. Escalante
- *Address correspondence to Ananias A. Escalante, Institute for Genomics and Evolutionary Medicine, Temple University, SERC Building, 1925 N. 12th Street Philadelphia, PA 19122-1801, E-mail: or Marcelo U. Ferreira, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, Avenida Professor Lineu Prestes, 1374 - Edifício Biomédicas II, São Paulo, Brazil CEP CEP 05508-900, E-mail: or Ingrid Felger, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland, E-mail:
| | - Marcelo U. Ferreira
- *Address correspondence to Ananias A. Escalante, Institute for Genomics and Evolutionary Medicine, Temple University, SERC Building, 1925 N. 12th Street Philadelphia, PA 19122-1801, E-mail: or Marcelo U. Ferreira, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, Avenida Professor Lineu Prestes, 1374 - Edifício Biomédicas II, São Paulo, Brazil CEP CEP 05508-900, E-mail: or Ingrid Felger, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland, E-mail:
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Ingrid Felger
- *Address correspondence to Ananias A. Escalante, Institute for Genomics and Evolutionary Medicine, Temple University, SERC Building, 1925 N. 12th Street Philadelphia, PA 19122-1801, E-mail: or Marcelo U. Ferreira, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, Avenida Professor Lineu Prestes, 1374 - Edifício Biomédicas II, São Paulo, Brazil CEP CEP 05508-900, E-mail: or Ingrid Felger, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland, E-mail:
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33
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Koepfli C, Robinson LJ, Rarau P, Salib M, Sambale N, Wampfler R, Betuela I, Nuitragool W, Barry AE, Siba P, Felger I, Mueller I. Blood-Stage Parasitaemia and Age Determine Plasmodium falciparum and P. vivax Gametocytaemia in Papua New Guinea. PLoS One 2015; 10:e0126747. [PMID: 25996916 PMCID: PMC4440770 DOI: 10.1371/journal.pone.0126747] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 04/07/2015] [Indexed: 12/18/2022] Open
Abstract
A better understanding of human-to-mosquito transmission is crucial to control malaria. In order to assess factors associated with gametocyte carriage, 2083 samples were collected in a cross-sectional survey in Papua New Guinea. Plasmodium species were detected by light microscopy and qPCR and gametocytes by detection of pfs25 and pvs25 mRNA transcripts by reverse-transcriptase PCR (qRT-PCR). The parasite prevalence by PCR was 18.5% for Plasmodium falciparum and 13.0% for P. vivax. 52.5% of all infections were submicroscopic. Gametocytes were detected in 60% of P. falciparum-positive and 51% of P. vivax-positive samples. Each 10-fold increase in parasite density led to a 1.8-fold and 3.3-fold increase in the odds of carrying P. falciparum and P. vivax gametocytes. Thus the proportion of gametocyte positive and gametocyte densities was highest in young children carrying high asexual parasite densities and in symptomatic individuals. Dilution series of gametocytes allowed absolute quantification of gametocyte densities by qRT-PCR and showed that pvs25 expression is 10-20 fold lower than pfs25 expression. Between 2006 and 2010 parasite prevalence in the study site has decreased by half. 90% of the remaining infections were asymptomatic and likely constitute an important reservoir of transmission. However, mean gametocyte densities were low (approx. 1-2 gametocyte/μL) and it remains to be determined to what extent low-density gametocyte positive individuals are infective to mosquitos.
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Affiliation(s)
- Cristian Koepfli
- Walter and Eliza Hall Institute, Population Health and Immunity Division, Parkville, Victoria, Australia
- University of Melbourne, Department of Medical Biology, Parkville, Victoria, Australia
| | - Leanne J. Robinson
- Walter and Eliza Hall Institute, Population Health and Immunity Division, Parkville, Victoria, Australia
- University of Melbourne, Department of Medical Biology, Parkville, Victoria, Australia
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, Papua New Guinea
| | - Patricia Rarau
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, Papua New Guinea
| | - Mary Salib
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, Papua New Guinea
| | - Naomi Sambale
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, Papua New Guinea
| | - Rahel Wampfler
- Swiss Tropical and Public Health Institute, Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Inoni Betuela
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, Papua New Guinea
| | - Wang Nuitragool
- Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Alyssa E. Barry
- Walter and Eliza Hall Institute, Population Health and Immunity Division, Parkville, Victoria, Australia
- University of Melbourne, Department of Medical Biology, Parkville, Victoria, Australia
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, Papua New Guinea
| | - Ingrid Felger
- Swiss Tropical and Public Health Institute, Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Ivo Mueller
- Walter and Eliza Hall Institute, Population Health and Immunity Division, Parkville, Victoria, Australia
- University of Melbourne, Department of Medical Biology, Parkville, Victoria, Australia
- ISGlobal, Barcelona Centre for International Health Research, Barcelona, Spain
- * E-mail:
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34
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Barry AE, Waltmann A, Koepfli C, Barnadas C, Mueller I. Uncovering the transmission dynamics of Plasmodium vivax using population genetics. Pathog Glob Health 2015; 109:142-52. [PMID: 25891915 DOI: 10.1179/2047773215y.0000000012] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Population genetic analysis of malaria parasites has the power to reveal key insights into malaria epidemiology and transmission dynamics with the potential to deliver tools to support control and elimination efforts. Analyses of parasite genetic diversity have suggested that Plasmodium vivax populations are more genetically diverse and less structured than those of Plasmodium falciparum indicating that P. vivax may be a more ancient parasite of humans and/or less susceptible to population bottlenecks, as well as more efficient at disseminating its genes. These population genetic insights into P. vivax transmission dynamics provide an explanation for its relative resilience to control efforts. Here, we describe current knowledge on P. vivax population genetic structure, its relevance to understanding transmission patterns and relapse and how this information can inform malaria control and elimination programmes.
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Key Words
- Control,
- Elimination
- Genetic diversity,
- Genetics,
- Genomics,
- Linkage disequilibrium,
- Malaria,
- Microsatellites,
- Mitochondrial DNA,
- Plasmodium vivax,
- Population structure,
- Relapse,
- Single nucleotide polymorphisms,
- Transmission,
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35
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Tessema SK, Monk SL, Schultz MB, Tavul L, Reeder JC, Siba PM, Mueller I, Barry AE. Phylogeography of var gene repertoires reveals fine-scale geospatial clustering of Plasmodium falciparum populations in a highly endemic area. Mol Ecol 2015; 24:484-97. [PMID: 25482097 DOI: 10.1111/mec.13033] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 11/14/2014] [Accepted: 11/17/2014] [Indexed: 11/28/2022]
Abstract
Plasmodium falciparum malaria is a major global health problem that is being targeted for progressive elimination. Knowledge of local disease transmission patterns in endemic countries is critical to these elimination efforts. To investigate fine-scale patterns of malaria transmission, we have compared repertoires of rapidly evolving var genes in a highly endemic area. A total of 3680 high-quality DBLα-sequences were obtained from 68 P. falciparum isolates from ten villages spread over two distinct catchment areas on the north coast of Papua New Guinea (PNG). Modelling of the extent of var gene diversity in the two parasite populations predicts more than twice as many var gene alleles circulating within each catchment (Mugil = 906; Wosera = 1094) than previously recognized in PNG (Amele = 369). In addition, there were limited levels of var gene sharing between populations, consistent with local parasite population structure. Phylogeographic analyses demonstrate that while neutrally evolving microsatellite markers identified population structure only at the catchment level, var gene repertoires reveal further fine-scale geospatial clustering of parasite isolates. The clustering of parasite isolates by village in Mugil, but not in Wosera was consistent with the physical and cultural isolation of the human populations in the two catchments. The study highlights the microheterogeneity of P. falciparum transmission in highly endemic areas and demonstrates the potential of var genes as markers of local patterns of parasite population structure.
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Affiliation(s)
- Sofonias K Tessema
- Division of Infection and Immunity, Walter and Eliza Hall Institute, 3052, Melbourne, Vic., Australia; Department of Medical Biology, University of Melbourne, 3052, Melbourne, Vic., Australia
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36
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Terheggen U, Drew DR, Hodder AN, Cross NJ, Mugyenyi CK, Barry AE, Anders RF, Dutta S, Osier FHA, Elliott SR, Senn N, Stanisic DI, Marsh K, Siba PM, Mueller I, Richards JS, Beeson JG. Limited antigenic diversity of Plasmodium falciparum apical membrane antigen 1 supports the development of effective multi-allele vaccines. BMC Med 2014; 12:183. [PMID: 25319190 PMCID: PMC4212128 DOI: 10.1186/s12916-014-0183-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 09/10/2014] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Polymorphism in antigens is a common mechanism for immune evasion used by many important pathogens, and presents major challenges in vaccine development. In malaria, many key immune targets and vaccine candidates show substantial polymorphism. However, knowledge on antigenic diversity of key antigens, the impact of polymorphism on potential vaccine escape, and how sequence polymorphism relates to antigenic differences is very limited, yet crucial for vaccine development. Plasmodium falciparum apical membrane antigen 1 (AMA1) is an important target of naturally-acquired antibodies in malaria immunity and a leading vaccine candidate. However, AMA1 has extensive allelic diversity with more than 60 polymorphic amino acid residues and more than 200 haplotypes in a single population. Therefore, AMA1 serves as an excellent model to assess antigenic diversity in malaria vaccine antigens and the feasibility of multi-allele vaccine approaches. While most previous research has focused on sequence diversity and antibody responses in laboratory animals, little has been done on the cross-reactivity of human antibodies. METHODS We aimed to determine the extent of antigenic diversity of AMA1, defined by reactivity with human antibodies, and to aid the identification of specific alleles for potential inclusion in a multi-allele vaccine. We developed an approach using a multiple-antigen-competition enzyme-linked immunosorbent assay (ELISA) to examine cross-reactivity of naturally-acquired antibodies in Papua New Guinea and Kenya, and related this to differences in AMA1 sequence. RESULTS We found that adults had greater cross-reactivity of antibodies than children, although the patterns of cross-reactivity to alleles were the same. Patterns of antibody cross-reactivity were very similar between populations (Papua New Guinea and Kenya), and over time. Further, our results show that antigenic diversity of AMA1 alleles is surprisingly restricted, despite extensive sequence polymorphism. Our findings suggest that a combination of three different alleles, if selected appropriately, may be sufficient to cover the majority of antigenic diversity in polymorphic AMA1 antigens. Antigenic properties were not strongly related to existing haplotype groupings based on sequence analysis. CONCLUSIONS Antigenic diversity of AMA1 is limited and a vaccine including a small number of alleles might be sufficient for coverage against naturally-circulating strains, supporting a multi-allele approach for developing polymorphic antigens as malaria vaccines.
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Affiliation(s)
- Ulrich Terheggen
- The Burnet Institute of Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, 3004, Australia. .,Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia.
| | - Damien R Drew
- The Burnet Institute of Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, 3004, Australia.
| | | | - Nadia J Cross
- The Burnet Institute of Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, 3004, Australia.
| | - Cleopatra K Mugyenyi
- Centre for Geographic Medicine, Coast, Kenya Medical Research Institute, Kilifi, Kenya.
| | - Alyssa E Barry
- Walter and Eliza Hall Institute, Melbourne, Australia. .,Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia.
| | | | | | - Faith H A Osier
- Centre for Geographic Medicine, Coast, Kenya Medical Research Institute, Kilifi, Kenya.
| | - Salenna R Elliott
- The Burnet Institute of Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, 3004, Australia.
| | - Nicolas Senn
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea. .,Swiss Tropical and Public Health Institute, Basel, Switzerland.
| | - Danielle I Stanisic
- Walter and Eliza Hall Institute, Melbourne, Australia. .,Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.
| | - Kevin Marsh
- Centre for Geographic Medicine, Coast, Kenya Medical Research Institute, Kilifi, Kenya.
| | - Peter M Siba
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.
| | - Ivo Mueller
- Walter and Eliza Hall Institute, Melbourne, Australia. .,Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia. .,Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.
| | - Jack S Richards
- The Burnet Institute of Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, 3004, Australia. .,Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia. .,Department of Microbiology, Monash University, Clayton, Victoria, Australia.
| | - James G Beeson
- The Burnet Institute of Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, 3004, Australia. .,Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia. .,Department of Microbiology, Monash University, Clayton, Victoria, Australia.
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Abstract
BACKGROUND Little is known about rates of alcohol consumption in career firefighters. AIMS To assess the quantity and frequency of alcohol consumption among career firefighters and the covariates that influence consumption levels. METHODS A convenience sample of career firefighters completed an online, self-administered, health assessment survey. Hierarchical binary logistic regression assessed the ability of several covariates to predict binge drinking status. RESULTS The majority of the sample (n = 160) consumed alcohol (89%), with approximately one-third (34%) having a drinking binge in the past 30 days. The regression model explained 13-18% of the variance in binge drinking status and correctly classified 71% of cases. Race (P < 0.05) and time of service (P < 0.01) were the only covariates that made a statistically significant contribution to the model. After controlling for other factors in the model, white respondents were ~4.5 times more likely to binge drink than non-white respondents (95% CI: 1.15-17.4). For each additional year of service, firefighters were 1.08 times less likely to binge drink (95% CI: 0.87-0.97). CONCLUSIONS Drinking levels observed in this study exceed those of the general adult population, including college students. Thus, it appears that firefighters represent an at-risk drinking group. Further investigations addressing reasons for alcohol use and abuse among firefighters are warranted. This study and subsequent research will provide information necessary for the development and testing of tailored interventions aimed at reducing firefighter alcohol consumption.
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Affiliation(s)
- A K Piazza-Gardner
- Department of Health Education and Behavior, University of Florida, Gainesville, FL 32611, USA,
| | - A E Barry
- Department of Health Education and Behavior, University of Florida, Gainesville, FL 32611, USA
| | - E Chaney
- Department of Health Education and Promotion, East Carolina University, Greenville, NC 27858, USA
| | - V Dodd
- Department of Community Dentistry and Behavioral Science, University of Florida, Gainesville, FL 32610, USA
| | - R Weiler
- Department of Global and Community Health, George Mason University, Fairfax, VA 22042, USA
| | - A Delisle
- Department of Health Education and Behavior, University of Florida, Gainesville, FL 32611, USA
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Abstract
After more than 50 years of intensive research and development, only one malaria vaccine candidate, “RTS,S,” has progressed to Phase 3 clinical trials. Despite only partial efficacy, this candidate is now forecast to become the first licensed malaria vaccine. Hence, more efficacious second-generation malaria vaccines that can significantly reduce transmission are urgently needed. This review will focus on a major obstacle hindering development of effective malaria vaccines: parasite antigenic diversity. Despite extensive genetic diversity in leading candidate antigens, vaccines have been and continue to be formulated using recombinant antigens representing only one or two strains. These vaccine strains represent only a small fraction of the diversity circulating in natural parasite populations, leading to escape of non-vaccine strains and challenging investigators’ abilities to measure strain-specific efficacy in vaccine trials. Novel strategies are needed to overcome antigenic diversity in order for vaccine development to succeed. Many studies have now cataloged the global diversity of leading Plasmodium falciparum and Plasmodium vivax vaccine antigens. In this review, we describe how population genetic approaches can be applied to this rich data source to predict the alleles that best represent antigenic diversity, polymorphisms that contribute to it, and to identify key polymorphisms associated with antigenic escape. We also suggest an approach to summarize the known global diversity of a given antigen to predict antigenic diversity, how to select variants that best represent the strains circulating in natural parasite populations and how to investigate the strain-specific efficacy of vaccine trials. Use of these strategies in the design and monitoring of vaccine trials will not only shed light on the contribution of genetic diversity to the antigenic diversity of malaria, but will also maximize the potential of future malaria vaccine candidates.
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Affiliation(s)
- Alyssa E Barry
- Division of Infection and Immunity, Walter and Eliza Hall Institute of Medical Research , Parkville, VIC , Australia ; Department of Medical Biology, The University of Melbourne , Parkville, VIC , Australia
| | - Alicia Arnott
- Division of Infection and Immunity, Walter and Eliza Hall Institute of Medical Research , Parkville, VIC , Australia ; Department of Medical Biology, The University of Melbourne , Parkville, VIC , Australia
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Arnott A, Wapling J, Mueller I, Ramsland PA, Siba PM, Reeder JC, Barry AE. Distinct patterns of diversity, population structure and evolution in the AMA1 genes of sympatric Plasmodium falciparum and Plasmodium vivax populations of Papua New Guinea from an area of similarly high transmission. Malar J 2014; 13:233. [PMID: 24930015 PMCID: PMC4085730 DOI: 10.1186/1475-2875-13-233] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 05/22/2014] [Indexed: 12/19/2022] Open
Abstract
Background As Plasmodium falciparum and Plasmodium vivax co-exist in most malaria-endemic regions outside sub-Saharan Africa, malaria control strategies in these areas must target both species in order to succeed. Population genetic analyses can predict the effectiveness of interventions including vaccines, by providing insight into patterns of diversity and evolution. The aim of this study was to investigate the population genetics of leading malaria vaccine candidate AMA1 in sympatric P. falciparum and P. vivax populations of Papua New Guinea (PNG), an area of similarly high prevalence (Pf = 22.3 to 38.8%, Pv = 15.3 to 31.8%). Methods A total of 72 Pfama1 and 102 Pvama1 sequences were collected from two distinct areas, Madang and Wosera, on the highly endemic PNG north coast. Results Despite a greater number of polymorphic sites in the AMA1 genes of P. falciparum (Madang = 52; Wosera = 56) compared to P. vivax (Madang = 36, Wosera = 34), the number of AMA1 haplotypes, haplotype diversity (Hd) and recombination (R) was far lower for P. falciparum (Madang = 12, Wosera = 20; Hd ≤0.92, R ≤45.8) than for P. vivax (Madang = 50, Wosera = 38; Hd = 0.99, R = ≤70.9). Balancing selection was detected only within domain I of AMA1 for P. vivax, and in both domains I and III for P. falciparum. Conclusions Higher diversity in the genes encoding P. vivax AMA1 than in P. falciparum AMA1 in this highly endemic area has important implications for development of AMA1-based vaccines in PNG and beyond. These results also suggest a smaller effective population size of P. falciparum compared to P. vivax, a finding that warrants further investigation. Differing patterns of selection on the AMA1 genes indicate that critical antigenic sites may differ between the species, highlighting the need for independent investigations of these two leading vaccine candidates.
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Affiliation(s)
| | | | | | | | | | | | - Alyssa E Barry
- Division of Infection and Immunity, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.
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Stanisic DI, Barry AE, Good MF. Escaping the immune system: How the malaria parasite makes vaccine development a challenge. Trends Parasitol 2013; 29:612-22. [DOI: 10.1016/j.pt.2013.10.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 10/01/2013] [Accepted: 10/01/2013] [Indexed: 10/26/2022]
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Arnott A, Mueller I, Ramsland PA, Siba PM, Reeder JC, Barry AE. Global Population Structure of the Genes Encoding the Malaria Vaccine Candidate, Plasmodium vivax Apical Membrane Antigen 1 (PvAMA1). PLoS Negl Trop Dis 2013; 7:e2506. [PMID: 24205419 PMCID: PMC3814406 DOI: 10.1371/journal.pntd.0002506] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 09/16/2013] [Indexed: 12/22/2022] Open
Abstract
Background The Plasmodium vivax Apical Membrane Antigen 1 (PvAMA1) is a promising malaria vaccine candidate, however it remains unclear which regions are naturally targeted by host immunity and whether its high genetic diversity will preclude coverage by a monovalent vaccine. To assess its feasibility as a vaccine candidate, we investigated the global population structure of PvAMA1. Methodology and Principal Findings New sequences from Papua New Guinea (PNG, n = 102) were analysed together with published sequences from Thailand (n = 158), India (n = 8), Sri Lanka (n = 23), Venezuela (n = 74) and a collection of isolates from disparate geographic locations (n = 8). A total of 92 single nucleotide polymorphisms (SNPs) were identified including 22 synonymous SNPs and 70 non-synonymous (NS) SNPs. Polymorphisms and signatures of balancing (positive Tajima's D and low FST values) selection were predominantly clustered in domain I, suggesting it is a dominant target of protective immune responses. To estimate global antigenic diversity, haplotypes comprised of (i) non-singleton (n = 40) and (ii) common (≥10% minor allele frequency, n = 23) polymorphic amino acid sites were then analysed revealing a total of 219 and 210 distinct haplotypes, respectively. Although highly diverse, the 210 haplotypes comprised of only common polymorphisms were grouped into eleven clusters, however substantial geographic differentiation was observed, and this may have implications for the efficacy of PvAMA1 vaccines in different malaria-endemic areas. The PNG haplotypes form a distinct group of clusters not found in any other geographic region. Vaccine haplotypes were rare and geographically restricted, suggesting potentially poor efficacy of candidate PvAMA1 vaccines. Conclusions It may be possible to cover the existing global PvAMA1 diversity by selection of diverse alleles based on these analyses however it will be important to first define the relationships between the genetic and antigenic diversity of this molecule. Traditionally misclassified as benign and neglected as a research priority, it is now understood that P. vivax is an increasingly important cause of human malaria. This important human pathogen poses an enormous obstacle to malaria control and elimination efforts due its broad geographic distribution, ability to cause recurring episodes of malaria after long periods of inactivity and extreme biodiversity. Vaccines are an essential component of global malaria control and elimination campaigns but the diversity of malaria antigens is thought to be a major cause of vaccine failure. Furthermore, at present the majority of current vaccine research is directed toward P. falciparum. The aims of this study were to investigate the global diversity of the P. vivax vaccine candidate, Apical Membrane Antigen 1 (PvAMA1), to determine the feasibility of designing a globally effective PvAMA1 vaccine and to determine which region of PvAMA1 is targeted by host immune responses, in order to identify the most promising vaccine candidates. We report that PvAMA1 diversity is extremely high, and that PvAMA1 domain I is a dominant target of host immune responses. These analyses of PvAMA1 diversity from several geographic regions provide a framework to guide development of a broadly efficacious P. vivax vaccine.
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Affiliation(s)
- Alicia Arnott
- Centre for Biomedical Research, Burnet Institute, Melbourne, Australia
| | - Ivo Mueller
- Barcelona Centre for International Health Research, Barcelona, Spain
- Division of Infection and Immunity, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
| | - Paul A. Ramsland
- Centre for Biomedical Research, Burnet Institute, Melbourne, Australia
- Department of Immunology, Monash University, Melbourne, Australia
- Department of Surgery Austin Health, University of Melbourne, Heidelberg, Australia
- School of Biomedical Sciences, CHIRI Biosciences, Faculty of Health Sciences, Curtin University, Perth, Australia
| | - Peter M. Siba
- Papua New Guinea Institute for Medical Research, Goroka, Papua New Guinea
| | - John C. Reeder
- Centre for Population Health, Burnet Institute, Melbourne, Australia
- Department of Epidemiology and Preventative Medicine, Monash University, Melbourne, Australia
| | - Alyssa E. Barry
- Division of Infection and Immunity, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- * E-mail:
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Koepfli C, Timinao L, Antao T, Barry AE, Siba P, Mueller I, Felger I. A Large Plasmodium vivax Reservoir and Little Population Structure in the South Pacific. PLoS One 2013; 8:e66041. [PMID: 23823758 PMCID: PMC3688846 DOI: 10.1371/journal.pone.0066041] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 05/01/2013] [Indexed: 12/02/2022] Open
Abstract
Introduction The importance of Plasmodium vivax in malaria elimination is increasingly being recognized, yet little is known about its population size and population genetic structure in the South Pacific, an area that is the focus of intensified malaria control. Methods We have genotyped 13 microsatellite markers in 295 P. vivax isolates from four geographically distinct sites in Papua New Guinea (PNG) and one site from Solomon Islands, representing different transmission intensities. Results Diversity was very high with expected heterozygosity values ranging from 0.62 to 0.98 for the different markers. Effective population size was high (12′872 to 19′533 per site). In PNG population structuring was limited with moderate levels of genetic differentiation. FST values (adjusted for high diversity of markers) were 0.14–0.15. Slightly higher levels were observed between PNG populations and Solomon Islands (FST = 0.16). Conclusions Low levels of population structure despite geographical barriers to transmission are in sharp contrast to results from regions of low P. vivax endemicity. Prior to intensification of malaria control programs in the study area, parasite diversity and effective population size remained high.
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Affiliation(s)
- Cristian Koepfli
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Infection & Immunity Division, Walter & Eliza Hall Institute, Parkville, Victoria, Australia
| | - Lincoln Timinao
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- PNG Institute of Medical Research, Goroka, Papua New Guinea
| | - Tiago Antao
- Department of Biological Anthropology, University of Cambridge, Cambridge, United Kingdom
| | - Alyssa E. Barry
- Infection & Immunity Division, Walter & Eliza Hall Institute, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Peter Siba
- PNG Institute of Medical Research, Goroka, Papua New Guinea
| | - Ivo Mueller
- Infection & Immunity Division, Walter & Eliza Hall Institute, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
- Barcelona Centre for International Health Research, Barcelona, Spain
| | - Ingrid Felger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
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Arnott A, Barnadas C, Senn N, Siba P, Mueller I, Reeder JC, Barry AE. High genetic diversity of Plasmodium vivax on the north coast of Papua New Guinea. Am J Trop Med Hyg 2013; 89:188-94. [PMID: 23690553 DOI: 10.4269/ajtmh.12-0774] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Despite having the highest Plasmodium vivax burden in the world, molecular epidemiological data from Papua New Guinea (PNG) for this parasite remain limited. To investigate the molecular epidemiology of P. vivax in PNG, 574 isolates collected from four catchment sites in East Sepik (N = 1) and Madang (N = 3) Provinces were genotyped using the markers MS16 and msp1F3. Genetic diversity and prevalence of P. vivax was determined for all sites. Despite a P. vivax infection prevalence in the East Sepik (15%) catchments less than one-half the prevalence of the Madang catchments (27-35%), genetic diversity was similarly high in all populations (He = 0.77-0.98). High genetic diversity, despite a marked difference in infection prevalence, suggests a large reservoir of diversity in P. vivax populations of PNG. Significant reductions in transmission intensity may, therefore, be required to reduce the diversity of parasite populations in highly endemic countries such as PNG.
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Affiliation(s)
- Alicia Arnott
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.
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Barry AE, Schultz L, Senn N, Nale J, Kiniboro B, Siba PM, Mueller I, Reeder JC. High levels of genetic diversity of Plasmodium falciparum populations in Papua New Guinea despite variable infection prevalence. Am J Trop Med Hyg 2013; 88:718-25. [PMID: 23400571 PMCID: PMC3617858 DOI: 10.4269/ajtmh.12-0056] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 11/30/2012] [Indexed: 11/07/2022] Open
Abstract
High levels of genetic diversity in Plasmodium falciparum populations are an obstacle to malaria control. Here, we investigate the relationship between local variation in malaria epidemiology and parasite genetic diversity in Papua New Guinea (PNG). Cross-sectional malaria surveys were performed in 14 villages spanning four distinct malaria-endemic areas on the north coast, including one area that was sampled during the dry season. High-resolution msp2 genotyping of 2,147 blood samples identified 761 P. falciparum infections containing a total of 1,392 clones whose genotypes were used to measure genetic diversity. Considerable variability in infection prevalence and mean multiplicity of infection was observed at all of the study sites, with the area sampled during the dry season showing particularly striking local variability. Genetic diversity was strongly associated with multiplicity of infection but not with infection prevalence. In highly endemic areas, differences in infection prevalence may not translate into a decrease in parasite population diversity.
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Affiliation(s)
- Alyssa E Barry
- Centre for Population Health, Burnet Institute, Melbourne, Australia.
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Arnott A, Barry AE, Reeder JC. Understanding the population genetics of Plasmodium vivax is essential for malaria control and elimination. Malar J 2012; 11:14. [PMID: 22233585 PMCID: PMC3298510 DOI: 10.1186/1475-2875-11-14] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 01/10/2012] [Indexed: 11/22/2022] Open
Abstract
Traditionally, infection with Plasmodium vivax was thought to be benign and self-limiting, however, recent evidence has demonstrated that infection with P. vivax can also result in severe illness and death. Research into P. vivax has been relatively neglected and much remains unknown regarding the biology, pathogenesis and epidemiology of this parasite. One of the fundamental factors governing transmission and immunity is parasite diversity. An understanding of parasite population genetic structure is necessary to understand the epidemiology, diversity, distribution and dynamics of natural P. vivax populations. In addition, studying the population structure of genes under immune selection also enables investigation of the dynamic interplay between transmission and immunity, which is crucial for vaccine development. A lack of knowledge regarding the transmission and spread of P. vivax has been particularly highlighted in areas where malaria control and elimination programmes have made progress in reducing the burden of Plasmodium falciparum, yet P. vivax remains as a substantial obstacle. With malaria elimination back on the global agenda, mapping of global and local P. vivax population structure is essential prior to establishing goals for elimination and the roll-out of interventions. A detailed knowledge of the spatial distribution, transmission and clinical burden of P. vivax is required to act as a benchmark against which control targets can be set and measured. This paper presents an overview of what is known and what is yet to be fully understood regarding P. vivax population genetics, as well as the importance and application of P. vivax population genetics studies.
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Affiliation(s)
- Alicia Arnott
- Centre for Population Health, Burnet Institute, Melbourne, Australia
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Barry AE, Trieu A, Fowkes FJI, Pablo J, Kalantari-Dehaghi M, Jasinskas A, Tan X, Kayala MA, Tavul L, Siba PM, Day KP, Baldi P, Felgner PL, Doolan DL. The stability and complexity of antibody responses to the major surface antigen of Plasmodium falciparum are associated with age in a malaria endemic area. Mol Cell Proteomics 2011; 10:M111.008326. [PMID: 21825279 PMCID: PMC3226400 DOI: 10.1074/mcp.m111.008326] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Individuals that are exposed to malaria eventually develop immunity to the disease with one possible mechanism being the gradual acquisition of antibodies to the range of parasite variant surface antigens in their local area. Major antibody targets include the large and highly polymorphic Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) family of proteins. Here, we use a protein microarray containing 123 recombinant PfEMP1-DBLα domains (VAR) from Papua New Guinea to seroprofile 38 nonimmune children (<4 years) and 29 hyperimmune adults (≥15 years) from the same local area. The overall magnitude, prevalence and breadth of antibody response to VAR was limited at <2 years and 2–2.9 years, peaked at 3–4 years and decreased for adults compared with the oldest children. An increasing proportion of individuals recognized large numbers of VAR proteins (>20) with age, consistent with the breadth of response stabilizing with age. In addition, the antibody response was limited in uninfected children compared with infected children but was similar in adults irrespective of infection status. Analysis of the variant-specific response confirmed that the antibody signature expands with age and infection. This also revealed that the antibody signatures of the youngest children overlapped substantially, suggesting that they are exposed to the same subset of PfEMP1 variants. VAR proteins were either seroprevalent from early in life, (<3 years), from later in childhood (≥3 years) or rarely recognized. Group 2 VAR proteins (Cys2/MFK-REY+) were serodominant in infants (<1-year-old) and all other sequence subgroups became more seroprevalent with age. The results confirm that the anti-PfEMP1-DBLα antibody responses increase in magnitude and prevalence with age and further demonstrate that they increase in stability and complexity. The protein microarray approach provides a unique platform to rapidly profile variant-specific antibodies to malaria and suggests novel insights into the acquisition of immunity to malaria.
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Affiliation(s)
- Alyssa E Barry
- Centre for Population Health, Burnet Institute, Melbourne, Victoria 3004, Australia.
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Reeder JC, Wapling J, Mueller I, Siba PM, Barry AE. Population genetic analysis of the Plasmodium falciparum 6-cys protein Pf38 in Papua New Guinea reveals domain-specific balancing selection. Malar J 2011; 10:126. [PMID: 21569602 PMCID: PMC3112457 DOI: 10.1186/1475-2875-10-126] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 05/14/2011] [Indexed: 11/29/2022] Open
Abstract
Background The Plasmodium falciparum merozoite surface protein Pf38 is targeted by antibodies of malaria immune adults and has been shown to be under balancing (immune) selection in a Gambian parasite population, indicating potential as a malaria vaccine candidate. This study explores the population genetics of Pf38 in Papua New Guinea, to determine the extent and geographic distribution of diversity and to measure selective pressure along the length of the gene. Methods Using samples collected during community-based cross-sectional surveys in the Mugil and Wosera regions, the Pf38 genes of 59 P. falciparum isolates were amplified and sequenced. These sequences, along with previously sequenced Gambian and laboratory isolates, were then subjected to an array of population genetic analyses, examining polymorphisms, haplotype diversity and balancing selection. In addition to whole-gene analysis, the two 6-cys domains were considered separately, to investigate domain specific polymorphism and selection. Results Nineteen polymorphic sites were identified in the Pf 38 gene. Of these, 13 were found in the Gambia, 10 in Mugil and 8 in Wosera. Notably, the majority of common polymorphisms were confined to domain I. Although only moderate levels of nucleotide diversity were observed, the haplotype diversity was high in all populations, suggesting extensive recombination. Analyses of the full-length sequence provided only modest evidence for balancing selection. However, there was a strong contrast between domain I, which showed strong evidence for positive balancing selection, and domain II which was neutral. Analyses of the geographic distribution of Pf38 haplotypes showed that four haplotypes accounted for the majority of sequences found world-wide, but there were many more haplotypes unique to the African than the PNG populations. Conclusion This study confirmed previous findings that Pf38 is a polymorphic gene under balancing selection. However, analysing polymorphism and selection across the length of the gene painted a considerably different picture. Domain I is highly polymorphic and the target of significant balancing selection. In contrast, domain II is relatively conserved and does not show evidence of immune selective pressure. The findings have implications for future population genetic studies on vaccine candidates, showing that the biological context must also be considered as a framework for analysis.
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Chen DS, Barry AE, Leliwa-Sytek A, Smith TA, Peterson I, Brown SM, Migot-Nabias F, Deloron P, Kortok MM, Marsh K, Daily JP, Ndiaye D, Sarr O, Mboup S, Day KP. A molecular epidemiological study of var gene diversity to characterize the reservoir of Plasmodium falciparum in humans in Africa. PLoS One 2011; 6:e16629. [PMID: 21347415 PMCID: PMC3036650 DOI: 10.1371/journal.pone.0016629] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 01/06/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The reservoir of Plasmodium infection in humans has traditionally been defined by blood slide positivity. This study was designed to characterize the local reservoir of infection in relation to the diverse var genes that encode the major surface antigen of Plasmodium falciparum blood stages and underlie the parasite's ability to establish chronic infection and transmit from human to mosquito. METHODOLOGY/PRINCIPAL FINDINGS We investigated the molecular epidemiology of the var multigene family at local sites in Gabon, Senegal and Kenya which differ in parasite prevalence and transmission intensity. 1839 distinct var gene types were defined by sequencing DBLα domains in the three sites. Only 76 (4.1%) var types were found in more than one population indicating spatial heterogeneity in var types across the African continent. The majority of var types appeared only once in the population sample. Non-parametric statistical estimators predict in each population at minimum five to seven thousand distinct var types. Similar diversity of var types was seen in sites with different parasite prevalences. CONCLUSIONS/SIGNIFICANCE Var population genomics provides new insights into the epidemiology of P. falciparum in Africa where malaria has never been conquered. In particular, we have described the extensive reservoir of infection in local African sites and discovered a unique var population structure that can facilitate superinfection through minimal overlap in var repertoires among parasite genomes. Our findings show that var typing as a molecular surveillance system defines the extent of genetic complexity in the reservoir of infection to complement measures of malaria prevalence. The observed small scale spatial diversity of var genes suggests that var genetics could greatly inform current malaria mapping approaches and predict complex malaria population dynamics due to the import of var types to areas where no widespread pre-existing immunity in the population exists.
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Affiliation(s)
- Donald S. Chen
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
- Department of Medicine, New York University School of Medicine, New York, New York, United States of America
| | - Alyssa E. Barry
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
- Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, Oxford, United Kingdom
- Centre for Population Health, Burnet Institute, Melbourne, Australia
- Department of Medicine, Central and Eastern Clinical School, Monash University, Victoria, Australia
| | - Aleksandra Leliwa-Sytek
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Terry-Ann Smith
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Ingrid Peterson
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Stuart M. Brown
- Center for Health Informatics and Bioinformatics, New York University School of Medicine, New York, New York, United States of America
| | - Florence Migot-Nabias
- Institut de Recherche pour le Développement, Faculté de Pharmacie, Université Paris 5, Paris, France
| | - Philippe Deloron
- Institut de Recherche pour le Développement, Faculté de Pharmacie, Université Paris 5, Paris, France
| | - Moses M. Kortok
- Kenya Medical Research Institute, Centre for Geographic Medicine Research, Kilifi, Kenya
| | - Kevin Marsh
- Kenya Medical Research Institute, Centre for Geographic Medicine Research, Kilifi, Kenya
| | - Johanna P. Daily
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Daouda Ndiaye
- Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Ousmane Sarr
- Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Souleymane Mboup
- Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Karen P. Day
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
- Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, Oxford, United Kingdom
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Schultz L, Wapling J, Mueller I, Ntsuke PO, Senn N, Nale J, Kiniboro B, Buckee CO, Tavul L, Siba PM, Reeder JC, Barry AE. Multilocus haplotypes reveal variable levels of diversity and population structure of Plasmodium falciparum in Papua New Guinea, a region of intense perennial transmission. Malar J 2010; 9:336. [PMID: 21092231 PMCID: PMC3002378 DOI: 10.1186/1475-2875-9-336] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Accepted: 11/23/2010] [Indexed: 11/10/2022] Open
Abstract
Background The South West Pacific nation of Papua New Guinea has intense year round transmission of Plasmodium falciparum on the coast and in the low-lying inland areas. Local heterogeneity in the epidemiology of malaria suggests that parasites from multiple locations will need to be surveyed to define the population biology of P. falciparum in the region. This study describes the population genetics of P. falciparum in thirteen villages spread over four distinct catchment areas of Papua New Guinea. Methods Ten microsatellite loci were genotyped in 318 P. falciparum isolates from the parasite populations of two inland catchment areas, namely Wosera (number of villages (n) = 7) and Utu (n = 1) and; and two coastal catchments, Malala (n = 3) and Mugil (n = 3). Analysis of the resultant multilocus haplotypes was done at different spatial scales (2-336 km) to define the genetic diversity (allelic richness and expected heterozygosity), linkage disequilibrium and population structure throughout the study area. Results Although genetic diversity was high in all parasite populations, it was also variable with a lower allelic richness and expected heterozygosity for inland populations compared to those from the more accessible coast. This variability was not correlated with two proxy measures of transmission intensity, the infection prevalence and the proportion multiple infections. Random associations among the microsatellite loci were observed in all four catchments showing that a substantial degree of out-crossing occurs in the region. Moderate to very high levels of population structure were found but the amount of genetic differentiation (FST) did not correlate with geographic distance suggesting that parasite populations are fragmented. Population structure was also identified between villages within the Malala area, with the haplotypes of one parasite population clustering with the neighbouring catchment of Mugil. Conclusion The observed population genetics of P. falciparum in this region is likely to be a consequence of the high transmission intensity combined with the isolation of human and vector populations, especially those located inland and migration of parasites via human movement into coastal populations. The variable genetic diversity and population structure of P. falciparum has important implications for malaria control strategies and warrants further fine scale sampling throughout Papua New Guinea.
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Affiliation(s)
- Lee Schultz
- Centre for Population Health, Burnet Institute, Melbourne, Australia
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Reiling L, Richards JS, Fowkes FJI, Barry AE, Triglia T, Chokejindachai W, Michon P, Tavul L, Siba PM, Cowman AF, Mueller I, Beeson JG. Evidence that the erythrocyte invasion ligand PfRh2 is a target of protective immunity against Plasmodium falciparum malaria. J Immunol 2010; 185:6157-67. [PMID: 20962255 DOI: 10.4049/jimmunol.1001555] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abs targeting blood-stage Ags of Plasmodium falciparum are important in acquired immunity to malaria, but major targets remain unclear. The P. falciparum reticulocyte-binding homologs (PfRh) are key ligands used by merozoites during invasion of erythrocytes. PfRh2a and PfRh2b are functionally important members of this family and may be targets of protective immunity, but their potential role in human immunity has not been examined. We expressed eight recombinant proteins covering the entire PfRh2 common region, as well as PfRh2a- and PfRh2b-specific regions. Abs were measured among a cohort of 206 Papua New Guinean children who were followed prospectively for 6 mo for reinfection and malaria. At baseline, Abs were associated with increasing age and active infection. High levels of IgG to all PfRh2 protein constructs were strongly associated with protection from symptomatic malaria and high-density parasitemia. The predominant IgG subclasses were IgG1 and IgG3, with little IgG2 and IgG4 detected. To further understand the significance of PfRh2 as an immune target, we analyzed PfRh2 sequences and found that polymorphisms are concentrated in an N-terminal region of the protein and seem to be under diversifying selection, suggesting immune pressure. Cluster analysis arranged the sequences into two main groups, suggesting that many of the haplotypes identified may be antigenically similar. These findings provide evidence suggesting that PfRh2 is an important target of protective immunity in humans and that Abs act by controlling blood-stage parasitemia and support its potential for vaccine development.
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Affiliation(s)
- Linda Reiling
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
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