1
|
Sekine S, Chan CW, Kalkoa M, Yamar S, Iata H, Taleo G, Kc A, Kagaya W, Kido Y, Kaneko A. Tracing the origins of Plasmodium vivax resurgence after malaria elimination on Aneityum Island in Vanuatu. COMMUNICATIONS MEDICINE 2024; 4:91. [PMID: 38762604 PMCID: PMC11102431 DOI: 10.1038/s43856-024-00524-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 05/08/2024] [Indexed: 05/20/2024] Open
Abstract
BACKGROUND Five years after successful malaria elimination, Aneityum Island in Vanuatu experienced an outbreak of Plasmodium vivax of unknown origin in 2002. Epidemiological investigations revealed several potential sources of P. vivax. We aimed to identify the genetic origin of P. vivax responsible for the resurgence. METHODS Five P. vivax microsatellite markers were genotyped using DNA extracted from archived blood samples. A total of 69 samples from four P. vivax populations was included: 29 from the outbreak in 2002, seven from Aneityum in 1999 and 2000, 18 from visitors to Aneityum in 2000, and 15 from nearby Tanna Island in 2002. A neighbour-joining phylogenetic tree was constructed to elucidate the relationships among P. vivax isolates. STRUCTURE and principal component analysis were used to assess patterns of genetic structure. RESULTS Here we show distinct genetic origins of P. vivax during the outbreak on Aneityum. While the origin of most P. vivax lineages found during the outbreak remains unidentified, limited genetic diversity among these lineages is consistent with a rapid expansion from a recent common ancestor. Contemporaneous P. vivax from neighboring Tanna and potential relapse of P. vivax acquired from other islands in 1999 and 2000 are also identified as minor contributors to the outbreak. CONCLUSIONS Multiple reintroductions of P. vivax after elimination highlight the high receptivity and vulnerability to malaria resurgence in island settings of Vanuatu, despite robust surveillance and high community compliance to control measures.
Collapse
Affiliation(s)
- Sho Sekine
- Department of Virology, Graduate School of Medicine, and Osaka International Research Center for Infectious Diseases, Osaka Metropolitan University, Osaka, Japan
- Department of Medical Technology, Morinomiya University of Medical Sciences, Osaka, Japan
| | - Chim W Chan
- Department of Virology, Graduate School of Medicine, and Osaka International Research Center for Infectious Diseases, Osaka Metropolitan University, Osaka, Japan
| | - Morris Kalkoa
- National Malaria and other Vector Borne Diseases Control Program (NVBDCP), Ministry of Health, Port Vila, Vanuatu
| | - Sam Yamar
- National Malaria and other Vector Borne Diseases Control Program (NVBDCP), Ministry of Health, Port Vila, Vanuatu
| | - Harry Iata
- National Malaria and other Vector Borne Diseases Control Program (NVBDCP), Ministry of Health, Port Vila, Vanuatu
| | - George Taleo
- National Malaria and other Vector Borne Diseases Control Program (NVBDCP), Ministry of Health, Port Vila, Vanuatu
| | - Achyut Kc
- Department of Virology, Graduate School of Medicine, and Osaka International Research Center for Infectious Diseases, Osaka Metropolitan University, Osaka, Japan
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Wataru Kagaya
- Department of Virology, Graduate School of Medicine, and Osaka International Research Center for Infectious Diseases, Osaka Metropolitan University, Osaka, Japan
- Department of Eco-epidemiology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Yasutoshi Kido
- Department of Virology, Graduate School of Medicine, and Osaka International Research Center for Infectious Diseases, Osaka Metropolitan University, Osaka, Japan
| | - Akira Kaneko
- Department of Virology, Graduate School of Medicine, and Osaka International Research Center for Infectious Diseases, Osaka Metropolitan University, Osaka, Japan.
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
| |
Collapse
|
2
|
Kattenberg JH, Monsieurs P, De Meyer J, De Meulenaere K, Sauve E, de Oliveira TC, Ferreira MU, Gamboa D, Rosanas‐Urgell A. Population genomic evidence of structured and connected Plasmodium vivax populations under host selection in Latin America. Ecol Evol 2024; 14:e11103. [PMID: 38529021 PMCID: PMC10961478 DOI: 10.1002/ece3.11103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 02/15/2024] [Accepted: 02/20/2024] [Indexed: 03/27/2024] Open
Abstract
Pathogen genomic epidemiology has the potential to provide a deep understanding of population dynamics, facilitating strategic planning of interventions, monitoring their impact, and enabling timely responses, and thereby supporting control and elimination efforts of parasitic tropical diseases. Plasmodium vivax, responsible for most malaria cases outside Africa, shows high genetic diversity at the population level, driven by factors like sub-patent infections, a hidden reservoir of hypnozoites, and early transmission to mosquitoes. While Latin America has made significant progress in controlling Plasmodium falciparum, it faces challenges with residual P. vivax. To characterize genetic diversity and population structure and dynamics, we have analyzed the largest collection of P. vivax genomes to date, including 1474 high-quality genomes from 31 countries across Asia, Africa, Oceania, and America. While P. vivax shows high genetic diversity globally, Latin American isolates form a distinctive population, which is further divided into sub-populations and occasional clonal pockets. Genetic diversity within the continent was associated with the intensity of transmission. Population differentiation exists between Central America and the North Coast of South America, vs. the Amazon Basin, with significant gene flow within the Amazon Basin, but limited connectivity between the Northwest Coast and the Amazon Basin. Shared genomic regions in these parasite populations indicate adaptive evolution, particularly in genes related to DNA replication, RNA processing, invasion, and motility - crucial for the parasite's survival in diverse environments. Understanding these population-level adaptations is crucial for effective control efforts, offering insights into potential mechanisms behind drug resistance, immune evasion, and transmission dynamics.
Collapse
Affiliation(s)
| | - Pieter Monsieurs
- Malariology UnitInstitute of Tropical Medicine AntwerpAntwerpBelgium
| | - Julie De Meyer
- Malariology UnitInstitute of Tropical Medicine AntwerpAntwerpBelgium
- Present address:
Integrated Molecular Plant physiology Research (IMPRES) and Plants and Ecosystems (PLECO), Department of BiologyUniversity of AntwerpAntwerpBelgium
| | | | - Erin Sauve
- Malariology UnitInstitute of Tropical Medicine AntwerpAntwerpBelgium
| | - Thaís C. de Oliveira
- Department of Parasitology, Institute of Biomedical SciencesUniversity of São PauloSão PauloBrazil
| | - Marcelo U. Ferreira
- Department of Parasitology, Institute of Biomedical SciencesUniversity of São PauloSão PauloBrazil
- Global Health and Tropical Medicine, Institute of Hygiene and Tropical MedicineNova University of LisbonLisbonPortugal
| | - Dionicia Gamboa
- Instituto de Medicina Tropical “Alexander von Humboldt”Universidad Peruana Cayetano HerediaLimaPeru
- Laboratorio de Malaria: Parásitos y Vectores, Laboratorios de Investigación y Desarrollo, Departamento de Ciencias Celulares y Moleculares, Facultad de Ciencias e IngenieríaUniversidad Peruana Cayetano HerediaLimaPeru
| | | |
Collapse
|
3
|
Kojom Foko LP, Singh V. Malaria in pregnancy in India: a 50-year bird's eye. Front Public Health 2023; 11:1150466. [PMID: 37927870 PMCID: PMC10620810 DOI: 10.3389/fpubh.2023.1150466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 09/25/2023] [Indexed: 11/07/2023] Open
Abstract
Introduction In 2021, India contributed for ~79% of malaria cases and ~ 83% of deaths in the South East Asia region. Here, we systematically and critically analyzed data published on malaria in pregnancy (MiP) in India. Methods Epidemiological, clinical, parasitological, preventive and therapeutic aspects of MiP and its consequences on both mother and child were reviewed and critically analyzed. Knowledge gaps and solution ways are also presented and discussed. Several electronic databases including Google scholar, Google, PubMed, Scopus, Wiley Online library, the Malaria in Pregnancy Consortium library, the World Malaria Report, The WHO regional websites, and ClinicalTrials.gov were used to identify articles dealing with MiP in India. The archives of local scientific associations/journals and website of national programs were also consulted. Results Malaria in pregnancy is mainly due to Plasmodium falciparum (Pf) and P. vivax (Pv), and on rare occasions to P. ovale spp. and P. malariae too. The overall prevalence of MiP is ~0.1-57.7% for peripheral malaria and ~ 0-29.3% for placental malaria. Peripheral Pf infection at antenatal care (ANC) visits decreased from ~13% in 1991 to ~7% in 1995-1996 in Madhya Pradesh, while placental Pf infection at delivery unit slightly decreased from ~1.5% in 2006-2007 to ~1% in 2012-2015 in Jharkhand. In contrast, the prevalence of peripheral Pv infection at ANC increased from ~1% in 2006-2007 to ~5% in 2015 in Jharkhand, and from ~0.5% in 1984-1985 to ~1.5% in 2007-2008 in Chhattisgarh. Clinical presentation of MiP is diverse ranging from asymptomatic carriage of parasites to severe malaria, and associated with comorbidities and concurrent infections such as malnutrition, COVID-19, dengue, and cardiovascular disorders. Severe anemia, cerebral malaria, severe thrombocytopenia, and hypoglycemia are commonly seen in severe MiP, and are strongly associated with tragic consequences such as abortion and stillbirth. Congenital malaria is seen at prevalence of ~0-12.9%. Infected babies are generally small-for-gestational age, premature with low birthweight, and suffer mainly from anemia, thrombocytopenia, leucopenia and clinical jaundice. Main challenges and knowledge gaps to MiP control included diagnosis, relapsing malaria, mixed Plasmodium infection treatment, self-medication, low density infections and utility of artemisinin-based combination therapies. Conclusion All taken together, the findings could be immensely helpful to control MiP in malaria endemic areas.
Collapse
|
4
|
Trimarsanto H, Amato R, Pearson RD, Sutanto E, Noviyanti R, Trianty L, Marfurt J, Pava Z, Echeverry DF, Lopera-Mesa TM, Montenegro LM, Tobón-Castaño A, Grigg MJ, Barber B, William T, Anstey NM, Getachew S, Petros B, Aseffa A, Assefa A, Rahim AG, Chau NH, Hien TT, Alam MS, Khan WA, Ley B, Thriemer K, Wangchuck S, Hamedi Y, Adam I, Liu Y, Gao Q, Sriprawat K, Ferreira MU, Laman M, Barry A, Mueller I, Lacerda MVG, Llanos-Cuentas A, Krudsood S, Lon C, Mohammed R, Yilma D, Pereira DB, Espino FEJ, Chu CS, Vélez ID, Namaik-Larp C, Villegas MF, Green JA, Koh G, Rayner JC, Drury E, Gonçalves S, Simpson V, Miotto O, Miles A, White NJ, Nosten F, Kwiatkowski DP, Price RN, Auburn S. A molecular barcode and web-based data analysis tool to identify imported Plasmodium vivax malaria. Commun Biol 2022; 5:1411. [PMID: 36564617 PMCID: PMC9789135 DOI: 10.1038/s42003-022-04352-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 12/08/2022] [Indexed: 12/25/2022] Open
Abstract
Traditionally, patient travel history has been used to distinguish imported from autochthonous malaria cases, but the dormant liver stages of Plasmodium vivax confound this approach. Molecular tools offer an alternative method to identify, and map imported cases. Using machine learning approaches incorporating hierarchical fixation index and decision tree analyses applied to 799 P. vivax genomes from 21 countries, we identified 33-SNP, 50-SNP and 55-SNP barcodes (GEO33, GEO50 and GEO55), with high capacity to predict the infection's country of origin. The Matthews correlation coefficient (MCC) for an existing, commonly applied 38-SNP barcode (BR38) exceeded 0.80 in 62% countries. The GEO panels outperformed BR38, with median MCCs > 0.80 in 90% countries at GEO33, and 95% at GEO50 and GEO55. An online, open-access, likelihood-based classifier framework was established to support data analysis (vivaxGEN-geo). The SNP selection and classifier methods can be readily amended for other use cases to support malaria control programs.
Collapse
Affiliation(s)
- Hidayat Trimarsanto
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Roberto Amato
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | | | - Edwin Sutanto
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
- Exeins Health Initiative, Jakarta, Indonesia
| | | | - Leily Trianty
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Jutta Marfurt
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Zuleima Pava
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Diego F Echeverry
- International Training and Medical Research Center (CIDEIM), Cali, Colombia
- Departamento de Microbiología, Universidad del Valle, Cali, Colombia
- Universidad Icesi, Cali, Colombia
| | | | | | | | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Bridget Barber
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Timothy William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
- Clinical Research Centre, Queen Elizabeth Hospital, Sabah, Malaysia
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Sisay Getachew
- College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Beyene Petros
- College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Abraham Aseffa
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | | | - Awab G Rahim
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Nangarhar Medical Faculty, Nangarhar University, Ministry of Higher Education, Jalalabad, Afghanistan
| | - Nguyen H Chau
- Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam
| | - Tran T Hien
- Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam
| | - Mohammad S Alam
- Infectious Diseases Division, International Centre for Diarrheal Diseases Research, Dhaka, Bangladesh
| | - Wasif A Khan
- Infectious Diseases Division, International Centre for Diarrheal Diseases Research, Dhaka, Bangladesh
| | - Benedikt Ley
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Kamala Thriemer
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Sonam Wangchuck
- Royal Center for Disease Control, Department of Public Health, Ministry of Health, Thimphu, Bhutan
| | - Yaghoob Hamedi
- Infectious and Tropical Diseases Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Hormozgan Province, Iran
| | - Ishag Adam
- Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | - Yaobao Liu
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China
- School of Public Health, Nanjing Medical University, Nanjing, China
| | - Qi Gao
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China
| | - Kanlaya Sriprawat
- Shoklo Malaria Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
| | - Marcelo U Ferreira
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- Global Health and Tropical Medicine, Institute of Hygiene and Tropical Medicine, NOVA University of Lisbon, Lisbon, Portugal
| | - Moses Laman
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Alyssa Barry
- Deakin University, Victoria, Australia
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Victoria, Australia
- Department of Medical Biology, The University of Melbourne, Victoria, Australia
| | - Ivo Mueller
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Victoria, Australia
- Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Marcus V G Lacerda
- Fundação de Medicina Tropical, Manaus, Brazil
- Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
| | | | | | - Chanthap Lon
- Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | | | | | | | - Fe E J Espino
- Research Institute for Tropical Medicine, Manilla, Philippines
| | - Cindy S Chu
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Shoklo Malaria Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
| | - Iván D Vélez
- Malaria Group, Universidad de Antioquia, Medellin, Colombia
| | | | | | | | | | - Julian C Rayner
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
- Cambridge Institute for Medical Research, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Eleanor Drury
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Sónia Gonçalves
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Victoria Simpson
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Olivo Miotto
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
| | - Alistair Miles
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Nicholas J White
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Francois Nosten
- Shoklo Malaria Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | - Ric N Price
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Sarah Auburn
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia.
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
| |
Collapse
|
5
|
Kattenberg JH, Nguyen HV, Nguyen HL, Sauve E, Nguyen NTH, Chopo-Pizarro A, Trimarsanto H, Monsieurs P, Guetens P, Nguyen XX, Esbroeck MV, Auburn S, Nguyen BTH, Rosanas-Urgell A. Novel highly-multiplexed AmpliSeq targeted assay for Plasmodium vivax genetic surveillance use cases at multiple geographical scales. Front Cell Infect Microbiol 2022; 12:953187. [PMID: 36034708 PMCID: PMC9403277 DOI: 10.3389/fcimb.2022.953187] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 07/19/2022] [Indexed: 11/17/2022] Open
Abstract
Although the power of genetic surveillance tools has been acknowledged widely, there is an urgent need in malaria endemic countries for feasible and cost-effective tools to implement in national malaria control programs (NMCPs) that can generate evidence to guide malaria control and elimination strategies, especially in the case of Plasmodium vivax. Several genetic surveillance applications (‘use cases’) have been identified to align research, technology development, and public health efforts, requiring different types of molecular markers. Here we present a new highly-multiplexed deep sequencing assay (Pv AmpliSeq). The assay targets the 33-SNP vivaxGEN-geo panel for country-level classification, and a newly designed 42-SNP within-country barcode for analysis of parasite dynamics in Vietnam and 11 putative drug resistance genes in a highly multiplexed NGS protocol with easy workflow, applicable for many different genetic surveillance use cases. The Pv AmpliSeq assay was validated using: 1) isolates from travelers and migrants in Belgium, and 2) routine collections of the national malaria control program at sentinel sites in Vietnam. The assay targets 229 amplicons and achieved a high depth of coverage (mean 595.7 ± 481) and high accuracy (mean error-rate of 0.013 ± 0.007). P. vivax parasites could be characterized from dried blood spots with a minimum of 5 parasites/µL and 10% of minority-clones. The assay achieved good spatial specificity for between-country prediction of origin using the 33-SNP vivaxGEN-geo panel that targets rare alleles specific for certain countries and regions. A high resolution for within-country diversity in Vietnam was achieved using the designed 42-SNP within-country barcode that targets common alleles (median MAF 0.34, range 0.01-0.49. Many variants were detected in (putative) drug resistance genes, with different predominant haplotypes in the pvmdr1 and pvcrt genes in different provinces in Vietnam. The capacity of the assay for high resolution identity-by-descent (IBD) analysis was demonstrated and identified a high rate of shared ancestry within Gia Lai Province in the Central Highlands of Vietnam, as well as between the coastal province of Binh Thuan and Lam Dong. Our approach performed well in geographically differentiating isolates at multiple spatial scales, detecting variants in putative resistance genes, and can be easily adjusted to suit the needs in other settings in a country or region. We prioritize making this tool available to researchers and NMCPs in endemic countries to increase ownership and ensure data usage for decision-making and malaria policy.
Collapse
Affiliation(s)
- Johanna Helena Kattenberg
- Biomedical Sciences Department, Institute of Tropical Medicine, Antwerp, Belgium
- *Correspondence: Johanna Helena Kattenberg, ; Anna Rosanas-Urgell,
| | - Hong Van Nguyen
- Department of Clinical Research, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Hieu Luong Nguyen
- Department of Clinical Research, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Erin Sauve
- Biomedical Sciences Department, Institute of Tropical Medicine, Antwerp, Belgium
| | - Ngoc Thi Hong Nguyen
- Department of Molecular Biology, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Ana Chopo-Pizarro
- Biomedical Sciences Department, Institute of Tropical Medicine, Antwerp, Belgium
| | - Hidayat Trimarsanto
- Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
| | - Pieter Monsieurs
- Biomedical Sciences Department, Institute of Tropical Medicine, Antwerp, Belgium
| | - Pieter Guetens
- Biomedical Sciences Department, Institute of Tropical Medicine, Antwerp, Belgium
| | - Xa Xuan Nguyen
- Department of Epidemiology, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Marjan Van Esbroeck
- Clinical Sciences Department, Institute of Tropical Medicine, Antwerp, Belgium
| | - Sarah Auburn
- Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
- Mahidol‐Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Binh Thi Huong Nguyen
- Department of Clinical Research, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Anna Rosanas-Urgell
- Biomedical Sciences Department, Institute of Tropical Medicine, Antwerp, Belgium
- *Correspondence: Johanna Helena Kattenberg, ; Anna Rosanas-Urgell,
| |
Collapse
|
6
|
Douglas NM, Burkot TR, Price RN. Malaria eradication revisited. Int J Epidemiol 2022; 51:382-392. [PMID: 34918106 DOI: 10.1093/ije/dyab259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 12/06/2021] [Indexed: 01/13/2023] Open
Affiliation(s)
- Nicholas M Douglas
- Department of Medicine, University of Otago, Christchurch, New Zealand.,Division of Global and Tropical Health, Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia.,Department of Infectious Diseases, Christchurch Hospital, Christchurch, New Zealand
| | - Thomas R Burkot
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
| | - Ric N Price
- Division of Global and Tropical Health, Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia.,Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| |
Collapse
|
7
|
Putaporntip C, Kuamsab N, Seethamchai S, Pattanawong U, Rojrung R, Yanmanee S, Cheng CW, Jongwutiwes S. Cryptic Plasmodium inui and P. fieldi infections among symptomatic malaria patients in Thailand. Clin Infect Dis 2021; 75:805-812. [PMID: 34971372 DOI: 10.1093/cid/ciab1060] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Some nonhuman primate Plasmodium species including P. knowlesi and P. cynomolgi can cross-transmit from macaque natural hosts to humans under natural infection. This study aims to retrospectively explore other simian Plasmodium species in the blood samples of symptomatic malaria patients in Thailand. METHODS A total of 5271 blood samples from acute febrile patients from 5 malaria endemic provinces and 1015 blood samples from long-tailed and pig-tailed macaques from 3 locations were examined for Plasmodium species by microscopy and species-specific polymerase chain reaction. The Plasmodium mitochondrial cytochrome oxidase 1 (COX1) gene was analyzed by amplicon deep sequencing as well as Sanger sequencing from recombinant plasmid clones to reaffirm and characterize P. inui and P. fieldi. RESULTS Besides human malaria, P. knowlesi, P. cynomolgi, P. inui and P. fieldi infections were diagnosed in 15, 21, 19 and 3 patients, respectively. Most P. inui and all P. fieldi infected patients had simultaneous infections with other Plasmodium species, and seemed to be responsive to chloroquine or artemisinin-mefloquine. P. inui was the most prevalent species among macaque populations. Phylogenetic analysis of the COX1 sequences from human and macaque isolates reveals the genetic diversity of P. inui and suggests that multiple parasite strains have been incriminated in human infections. CONCLUSIONS Both P. inui and P. fieldi could establish infection in humans under natural transmission. Despite occurring at a low prevalence and mostly co-existing with other Plasmodium species, P. inui infections in humans have a wide distribution in Thailand.
Collapse
Affiliation(s)
- Chaturong Putaporntip
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Napaporn Kuamsab
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Sunee Seethamchai
- Department of Biology, Faculty of Science, Naresuan University, Pitsanulok, Thailand
| | - Urassaya Pattanawong
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Rattanaporn Rojrung
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Surasuk Yanmanee
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Chew Weng Cheng
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, UK
| | - Somchai Jongwutiwes
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| |
Collapse
|
8
|
Angrisano F, Robinson LJ. Plasmodium vivax - How hidden reservoirs hinder global malaria elimination. Parasitol Int 2021; 87:102526. [PMID: 34896312 DOI: 10.1016/j.parint.2021.102526] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/03/2021] [Accepted: 12/04/2021] [Indexed: 01/23/2023]
Abstract
Plasmodium vivax is the most geographically widespread human malaria parasite. Global malaria efforts have been less successful at reducing the burden of P. vivax compared to P. falciparum, owing to the unique biology and related treatment complexity of P. vivax. As a result, P. vivax is now the dominant malaria parasite throughout the Asia-Pacific and South America causing up to 14 million clinical cases every year and is considered a major obstacle to malaria elimination. Key features circumventing existing malaria control tools are the transmissibility of asymptomatic, low-density circulating infections and reservoirs of persistent dormant liver stages (hypnozoites) that are undetectable but reactivate to cause relapsing infections and sustain transmission. In this review we summarise the new knowledge shaping our understanding of the global epidemiology of P. vivax infections, highlighting the challenges for elimination and the tools that will be required achieve this.
Collapse
|
9
|
Tayipto Y, Liu Z, Mueller I, Longley RJ. Serology for Plasmodium vivax surveillance: A novel approach to accelerate towards elimination. Parasitol Int 2021; 87:102492. [PMID: 34728377 DOI: 10.1016/j.parint.2021.102492] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/30/2021] [Accepted: 10/28/2021] [Indexed: 01/13/2023]
Abstract
Plasmodium vivax is the most widespread causative agent of human malaria in the world. Despite the ongoing implementation of malaria control programs, the rate of case reduction has declined over the last 5 years. Hence, surveillance of malaria transmission should be in place to identify and monitor areas that require intensified malaria control interventions. Serological tools may offer additional insights into transmission intensity over parasite and entomological measures, especially as transmission levels decline. Antibodies can be detected in the host system for months to even years after parasite infections have been cleared from the blood, enabling malaria exposure history to be captured. Because the Plasmodium parasite expresses more than 5000 proteins, it is important to a) understand antibody longevity following infection and b) measure antibodies to more than one antigen in order to accurately inform on the exposure and/or immune status of populations. This review summarises current practices for surveillance of P. vivax malaria, the current state of research into serological exposure markers and their potential role for accelerating malaria elimination, and discusses further studies that need to be undertaken to see such technology implemented in malaria-endemic areas.
Collapse
Affiliation(s)
- Yanie Tayipto
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Zoe Liu
- The Institute for Mental and Physical Health and Clinical Translation, Barwon Health, Deakin University, Geelong, Victoria, Australia; School of Medicine, Centre for Molecular and Medical Research, Deakin University, Geelong, Australia
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Rhea J Longley
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia.
| |
Collapse
|
10
|
Adhikari B, Awab GR, von Seidlein L. Rolling out the radical cure for vivax malaria in Asia: a qualitative study among policy makers and stakeholders. Malar J 2021; 20:164. [PMID: 33757538 PMCID: PMC7987122 DOI: 10.1186/s12936-021-03702-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 03/15/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Wide-spread implementation of treatment regimens for the radical cure of vivax malaria is hindered by a range of factors. This has resulted in an increase in the relative proportion of vivax malaria and is an important obstacle in the achievement of global malaria elimination by 2030. The main objective of this study was to explore the current policies guiding the treatment plans on vivax malaria, and the factors affecting the implementation of radical cure in South/South East Asian and Asian Pacific countries. METHODS This was a qualitative study among respondents who represented national malaria control programmes (NMCPs) or had a role and influence in the national malaria policies. 33 respondents from 17 countries in South/South East Asia and Asia Pacific participated in interviews between October 15 and December 15, 2020. Semi-structured interviews were conducted virtually except for two face to face interviews and audio-recorded. Transcribed audio-records underwent thematic analysis using QSR NVivo. RESULTS Policies against vivax malaria were underprioritized, compared with the focus on falciparum malaria and, in particular, drug resistant Plasmodium falciparum strains. Despite the familiarity with primaquine (PQ) as the essential treatment to achieve the radical cure, the respondents contested the need for G6PD testing. Optional G6PD testing was reported to have poor adherence. The fear of adverse events led health workers to hesitate prescribing PQ. In countries where G6PD was mandatory, respondents experienced frequent stockouts of G6PD rapid diagnostic kits in peripheral health facilities, which was compounded by a short shelf life of these tests. These challenges were echoed across participating countries to various degrees. Most respondents agreed that a shorter treatment regimen, such as single dose tafenoquine could resolve these problems but mandatory G6PD testing will be needed. The recommendation of shorter regimens including tafenoquine or high dose PQ requires operational evidence demonstrating the robust performance of point of care G6PD tests (biosensors). CONCLUSION There was sparse implementation and low adherence to the radical cure in South/South East Asian and Asian pacific countries. Shorter treatment regimens with appropriate point of care quantitative G6PD tests may resolve the current challenges. Operational evidence on point of care quantitative G6PD tests that includes the feasibility of integrating such tests into the radical cure regimen are critical to ensure its implementation.
Collapse
Affiliation(s)
- Bipin Adhikari
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
| | - Ghulam Rhahim Awab
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Nangarhar Medical Faculty, Nangarhar University, Jalalabad, Afghanistan
- Ministry of Higher Education, Kabul, Afghanistan
| | - Lorenz von Seidlein
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| |
Collapse
|
11
|
Nguyen TT, Nguyen XX, Ronse M, Nguyen QT, Ho PQ, Tran DT, Gerrets R, Thriemer K, Ley B, Marfurt J, Price RN, Grietens KP, Gryseels C. Diagnostic Practices and Treatment for P. vivax in the InterEthnic Therapeutic Encounter of South-Central Vietnam: A Mixed-Methods Study. Pathogens 2020; 10:pathogens10010026. [PMID: 33396538 PMCID: PMC7824694 DOI: 10.3390/pathogens10010026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/25/2020] [Accepted: 12/28/2020] [Indexed: 01/13/2023] Open
Abstract
Malaria elimination in the Greater Mekong Sub-Region is challenged by a rising proportion of malaria attributable to P. vivax. Primaquine (PQ) is effective in eliminating the parasite's dormant liver stages and can prevent relapsing infections, but it induces severe haemolysis in patients with Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency, highlighting the importance of testing enzyme activity prior to treatment. A mixed-method study was conducted in south-central Vietnam to explore the factors that affect acceptability of G6PD testing, treatment-seeking behaviors, and adherence to current regimens. The majority of respondents (75.7%) were unaware of the different parasite species and rather differentiated malaria by perceived severity. People sought a diagnosis if suspected of malaria fever but not if they perceived their fevers as mild. Most respondents agreed to take prescribed medication to treat asymptomatic infection (94.1%) and to continue medication even if they felt better (91.5%). Health professionals did not have G6PD diagnostic tools nor the means to prescribe PQ safely. Adherence to treatment was linked to trust in public providers, who were perceived to make therapeutic decisions in the interest of the patient. Greater focus on providing acceptable ways of assessing G6PD deficiency will be needed to ensure the timely elimination of malaria in Vietnam.
Collapse
Affiliation(s)
- Thuan Thi Nguyen
- National Institute of Malariology, Parasitology and Entomology (NIMPE), 34 Trung Van, Trung Van Ward, Nam Tu Liem District, Hanoi 10000, Vietnam; (X.X.N.); (Q.T.N.); (P.Q.H.); (D.T.T.)
- Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium; (M.R.); (K.P.G.); (C.G.)
- Correspondence: ; Tel.: +324-9679-1347
| | - Xa Xuan Nguyen
- National Institute of Malariology, Parasitology and Entomology (NIMPE), 34 Trung Van, Trung Van Ward, Nam Tu Liem District, Hanoi 10000, Vietnam; (X.X.N.); (Q.T.N.); (P.Q.H.); (D.T.T.)
| | - Maya Ronse
- Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium; (M.R.); (K.P.G.); (C.G.)
| | - Quynh Truc Nguyen
- National Institute of Malariology, Parasitology and Entomology (NIMPE), 34 Trung Van, Trung Van Ward, Nam Tu Liem District, Hanoi 10000, Vietnam; (X.X.N.); (Q.T.N.); (P.Q.H.); (D.T.T.)
| | - Phuc Quang Ho
- National Institute of Malariology, Parasitology and Entomology (NIMPE), 34 Trung Van, Trung Van Ward, Nam Tu Liem District, Hanoi 10000, Vietnam; (X.X.N.); (Q.T.N.); (P.Q.H.); (D.T.T.)
| | - Duong Thanh Tran
- National Institute of Malariology, Parasitology and Entomology (NIMPE), 34 Trung Van, Trung Van Ward, Nam Tu Liem District, Hanoi 10000, Vietnam; (X.X.N.); (Q.T.N.); (P.Q.H.); (D.T.T.)
| | - Rene Gerrets
- Amsterdam Institute for Social Science Research (AISSR), University of Amsterdam, Postbus 15718, 1001 NE Amsterdam, The Netherlands;
- Amsterdam Institute for Global Health and Development (AIGHD), AHTC, Tower C4, Paasheuvelweg 25, 1105 BP Amsterdam, The Netherlands
| | - Kamala Thriemer
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Rocklands Drive Casuarina, Darwin Northern Territory 0810, Australia; (K.T.); (B.L.); (J.M.); (R.N.P.)
| | - Benedikt Ley
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Rocklands Drive Casuarina, Darwin Northern Territory 0810, Australia; (K.T.); (B.L.); (J.M.); (R.N.P.)
| | - Jutta Marfurt
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Rocklands Drive Casuarina, Darwin Northern Territory 0810, Australia; (K.T.); (B.L.); (J.M.); (R.N.P.)
| | - Ric N. Price
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Rocklands Drive Casuarina, Darwin Northern Territory 0810, Australia; (K.T.); (B.L.); (J.M.); (R.N.P.)
- Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7LG, UK
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Koen Peeters Grietens
- Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium; (M.R.); (K.P.G.); (C.G.)
| | - Charlotte Gryseels
- Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium; (M.R.); (K.P.G.); (C.G.)
| |
Collapse
|
12
|
Spatial and genetic clustering of Plasmodium falciparum and Plasmodium vivax infections in a low-transmission area of Ethiopia. Sci Rep 2020; 10:19975. [PMID: 33203956 PMCID: PMC7672087 DOI: 10.1038/s41598-020-77031-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 11/02/2020] [Indexed: 11/23/2022] Open
Abstract
The distribution of malaria infections is heterogeneous in space and time, especially in low transmission settings. Understanding this clustering may allow identification and targeting of pockets of transmission. In Adama district, Ethiopia, Plasmodium falciparum and P. vivax malaria patients and controls were examined, together with household members and immediate neighbors. Rapid diagnostic test and quantitative PCR (qPCR) were used for the detection of infections that were genetically characterized by a panel of microsatellite loci for P. falciparum (26) and P. vivax (11), respectively. Individuals living in households of clinical P. falciparum patients were more likely to have qPCR detected P. falciparum infections (22.0%, 9/41) compared to individuals in control households (8.7%, 37/426; odds ratio, 2.9; 95% confidence interval, 1.3–6.4; P = .007). Genetically related P. falciparum, but not P. vivax infections showed strong clustering within households. Genotyping revealed a marked temporal cluster of P. falciparum infections, almost exclusively comprised of clinical cases. These findings uncover previously unappreciated transmission dynamics and support a rational approach to reactive case detection strategies for P. falciparum in Ethiopia.
Collapse
|
13
|
Plasmodium vivax in the Era of the Shrinking P. falciparum Map. Trends Parasitol 2020; 36:560-570. [PMID: 32407682 PMCID: PMC7297627 DOI: 10.1016/j.pt.2020.03.009] [Citation(s) in RCA: 112] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/25/2020] [Accepted: 03/26/2020] [Indexed: 01/13/2023]
Abstract
Plasmodium vivax is an important cause of malaria, associated with a significant public health burden. Whilst enhanced malaria-control activities have successfully reduced the incidence of Plasmodium falciparum malaria in many areas, there has been a consistent increase in the proportion of malaria due to P. vivax in regions where both parasites coexist. This article reviews the epidemiology and biology of P. vivax, how the parasite differs from P. falciparum, and the key features that render it more difficult to control and eliminate. Since transmission of the parasite is driven largely by relapses from dormant liver stages, its timely elimination will require widespread access to safe and effective radical cure.
Collapse
|
14
|
A molecular barcode to inform the geographical origin and transmission dynamics of Plasmodium vivax malaria. PLoS Genet 2020; 16:e1008576. [PMID: 32053607 PMCID: PMC7043780 DOI: 10.1371/journal.pgen.1008576] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 02/26/2020] [Accepted: 12/19/2019] [Indexed: 11/19/2022] Open
Abstract
Although Plasmodium vivax parasites are the predominant cause of malaria outside of sub-Saharan Africa, they not always prioritised by elimination programmes. P. vivax is resilient and poses challenges through its ability to re-emerge from dormancy in the human liver. With observed growing drug-resistance and the increasing reports of life-threatening infections, new tools to inform elimination efforts are needed. In order to halt transmission, we need to better understand the dynamics of transmission, the movement of parasites, and the reservoirs of infection in order to design targeted interventions. The use of molecular genetics and epidemiology for tracking and studying malaria parasite populations has been applied successfully in P. falciparum species and here we sought to develop a molecular genetic tool for P. vivax. By assembling the largest set of P. vivax whole genome sequences (n = 433) spanning 17 countries, and applying a machine learning approach, we created a 71 SNP barcode with high predictive ability to identify geographic origin (91.4%). Further, due to the inclusion of markers for within population variability, the barcode may also distinguish local transmission networks. By using P. vivax data from a low-transmission setting in Malaysia, we demonstrate the potential ability to infer outbreak events. By characterising the barcoding SNP genotypes in P. vivax DNA sourced from UK travellers (n = 132) to ten malaria endemic countries predominantly not used in the barcode construction, we correctly predicted the geographic region of infection origin. Overall, the 71 SNP barcode outperforms previously published genotyping methods and when rolled-out within new portable platforms, is likely to be an invaluable tool for informing targeted interventions towards elimination of this resilient human malaria.
Collapse
|
15
|
Cáceres Carrera L, Victoria C, Ramirez JL, Jackman C, Calzada JE, Torres R. Study of the epidemiological behavior of malaria in the Darien Region, Panama. 2015-2017. PLoS One 2019; 14:e0224508. [PMID: 31730618 PMCID: PMC6857920 DOI: 10.1371/journal.pone.0224508] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 10/15/2019] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Malaria is endemic in Darién and an assessment of the different factors affecting its epidemiology is crucial for the development of adequate strategies of surveillance, prevention, and disease control. The objective of this study was to determine the main characteristics of the epidemiological behavior of malaria in the Darien region. METHODS This research was comprised of a retrospective analysis to determine the incidence and malaria distribution in the Darien region from 2015 to 2017. We evaluated malaria indicators, disease distribution, incidence (by age group and sex), diagnostic methods, treatment, and control measures. In addition, we examined the cross-border migration activity and its possible contribution to the maintenance and distribution of malaria. RESULTS During the period of 2015-2017, we examined 41,141 thick blood smear samples, out of which 501 tested positive for malaria. Plasmodium vivax was responsible for 92.2% of those infections. Males comprised 62.7% of the total diagnosed cases. Meanwhile, a similar percentage, 62.7%, of the total cases were registered in economically active ages. The more frequent symptoms included fever (99.4%) and chills (97.4%), with 53.1% of cases registering between 2,000 and 6,000 parasites/μl of blood. The annual parasitic incidence (API) average was 3.0/1,000 inhabitants, while the slide positivity rate (SPR) was 1.2% and the annual blood examination rate (ABER) 22.5%. In Darién there is a constant internal and cross-border migration movement between Panama and Colombia. Malaria control measures consisted of the active and passive search of suspected cases and of the application of vector control measures. CONCLUSION This study provides an additional perspective on malaria epidemiology in Darién. Additional efforts are required to intensify malaria surveillance and to achieve an effective control, eventually moving closer to the objective of malaria elimination. At the same time, there is a need for more eco-epidemiological, entomological and migratory studies to determine how these factors contribute to the patterns of maintenance and dissemination of malaria.
Collapse
Affiliation(s)
- Lorenzo Cáceres Carrera
- Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama
- * E-mail:
| | | | - Jose L. Ramirez
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, Peoria, Illinois, United States of America
| | - Carmela Jackman
- Epidemiology Department of the Darién Region, Ministry of Health, Panama City, Panama
| | - José E. Calzada
- Direcction of Research and Technological Development, Gorgas Memorial Institute of Health Studies, Panama City, Panama
| | - Rolando Torres
- Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama
| |
Collapse
|
16
|
Thanapongpichat S, Khammanee T, Sawangjaroen N, Buncherd H, Tun AW. Genetic Diversity of Plasmodium vivax in Clinical Isolates from Southern Thailand using PvMSP1, PvMSP3 (PvMSP3α, PvMSP3β) Genes and Eight Microsatellite Markers. THE KOREAN JOURNAL OF PARASITOLOGY 2019; 57:469-479. [PMID: 31715687 PMCID: PMC6851248 DOI: 10.3347/kjp.2019.57.5.469] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 09/21/2019] [Indexed: 11/23/2022]
Abstract
Plasmodium vivax is usually considered morbidity in endemic areas of Asia, Central and South America, and some part of Africa. In Thailand, previous studies indicated the genetic diversity of P. vivax in malaria-endemic regions such as the western part of Thailand bordering with Myanmar. The objective of the study is to investigate the genetic diversity of P. vivax circulating in Southern Thailand by using 3 antigenic markers and 8 microsatellite markers. Dried blood spots were collected from Chumphon, Phang Nga, Ranong and, Surat Thani provinces of Thailand. By PCR, 3 distinct sizes of PvMSP3α, 2 sizes of PvMSP3β and 2 sizes of PvMSP1 F2 were detected based on the length of PCR products, respectively. PCR/RFLP analyses of these antigen genes revealed high levels of genetic diversity. The genotyping of 8 microsatellite loci showed high genetic diversity as indicated by high alleles per locus and high expected heterozygosity (HE). The genotyping markers also showed multiple-clones of infection. Mixed genotypes were detected in 4.8% of PvMSP3α, 29.1% in PvMSP3β and 55.3% of microsatellite markers. These results showed that there was high genetic diversity of P. vivax isolated from Southern Thailand, indicating that the genetic diversity of P. vivax in this region was comparable to those observed other areas of Thailand.
Collapse
Affiliation(s)
| | - Thunchanok Khammanee
- Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Nongyao Sawangjaroen
- Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Hansuk Buncherd
- Faculty of Medical Technology, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Aung Win Tun
- Faculty of Graduate Studies, Mahidol University, Salaya, Nakhon Pathom, Thailand
| |
Collapse
|
17
|
Auburn S, Getachew S, Pearson RD, Amato R, Miotto O, Trimarsanto H, Zhu SJ, Rumaseb A, Marfurt J, Noviyanti R, Grigg MJ, Barber B, William T, Goncalves SM, Drury E, Sriprawat K, Anstey NM, Nosten F, Petros B, Aseffa A, McVean G, Kwiatkowski DP, Price RN. Genomic Analysis of Plasmodium vivax in Southern Ethiopia Reveals Selective Pressures in Multiple Parasite Mechanisms. J Infect Dis 2019; 220:1738-1749. [PMID: 30668735 PMCID: PMC6804337 DOI: 10.1093/infdis/jiz016] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 01/18/2019] [Indexed: 01/12/2023] Open
Abstract
The Horn of Africa harbors the largest reservoir of Plasmodium vivax in the continent. Most of sub-Saharan Africa has remained relatively vivax-free due to a high prevalence of the human Duffy-negative trait, but the emergence of strains able to invade Duffy-negative reticulocytes poses a major public health threat. We undertook the first population genomic investigation of P. vivax from the region, comparing the genomes of 24 Ethiopian isolates against data from Southeast Asia to identify important local adaptions. The prevalence of the Duffy binding protein amplification in Ethiopia was 79%, potentially reflecting adaptation to Duffy negativity. There was also evidence of selection in a region upstream of the chloroquine resistance transporter, a putative chloroquine-resistance determinant. Strong signals of selection were observed in genes involved in immune evasion and regulation of gene expression, highlighting the need for a multifaceted intervention approach to combat P. vivax in the region.
Collapse
Affiliation(s)
- Sarah Auburn
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, United Kingdom
| | - Sisay Getachew
- College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Richard D Pearson
- Wellcome Sanger Institute, Hinxton, Cambridge
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Oxford, United Kingdom
| | - Roberto Amato
- Wellcome Sanger Institute, Hinxton, Cambridge
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Oxford, United Kingdom
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, Cambridge
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Oxford, United Kingdom
- Mahidol–Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
| | - Hidayat Trimarsanto
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
- Agency for Assessment and Application of Technology, Jakarta, Indonesia
| | - Sha Joe Zhu
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Oxford, United Kingdom
| | - Angela Rumaseb
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
| | - Jutta Marfurt
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
| | | | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Sabah, Malaysia
| | - Bridget Barber
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Sabah, Malaysia
| | - Timothy William
- Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Sabah, Malaysia
- Clinical Research Centre, Queen Elizabeth Hospital, Sabah, Malaysia
- Jesselton Medical Centre, Sabah, Malaysia
| | | | | | - Kanlaya Sriprawat
- Shoklo Malaria Research Unit, Mahidol–Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
| | - Francois Nosten
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, United Kingdom
- Shoklo Malaria Research Unit, Mahidol–Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
| | - Beyene Petros
- College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Abraham Aseffa
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Gil McVean
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Oxford, United Kingdom
| | - Dominic P Kwiatkowski
- Wellcome Sanger Institute, Hinxton, Cambridge
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Oxford, United Kingdom
| | - Ric N Price
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, United Kingdom
| |
Collapse
|
18
|
Elgoraish AG, Elzaki SEG, Ahmed RT, Ahmed AI, Fadlalmula HA, Abdalgader Mohamed S, Abdallah NI, Abdelgadir O, Ageep TB, El-Sayed BB. Epidemiology and distribution of Plasmodium vivax malaria in Sudan. Trans R Soc Trop Med Hyg 2019; 113:517-524. [PMID: 31162590 DOI: 10.1093/trstmh/trz044] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 03/18/2019] [Accepted: 05/06/2019] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Plasmodium vivax malaria has been recognised as an important cause of morbidity in several African countries. The prevalence was previously estimated as 2-5% in eastern Sudan. These estimates are observed to be rising and spreading continuously. The present study was undertaken to investigate the situation of distribution and epidemiology of P. vivax malaria in Sudan. METHODS Cross-sectional malaria surveys carried out in hospitals and health centres covered 21 sites in 10 states. Data and blood samples were collected from 1226 clinically investigated suspected malaria cases of both genders and all ages. Microscopically detected malaria parasites were confirmed by PCR. RESULTS The overall prevalence of P. vivax among the malaria cases was 26.6%. The prevalence showed significant variations between the states (p<0.001), which could be explained by differences in population movement, the presence of refugees and proximity to endemic neighbouring countries. It also varied significantly with residence status (p<0.001), reflecting the stability of transmission. CONCLUSION Although malaria in Sudan is still largely attributed to Plasmodium falciparum, P. vivax has been rising with worrying proportions and spreading to new areas. The emergence and marked increase of P. vivax poses new challenges to malaria treatment and control in Sudan.
Collapse
Affiliation(s)
- Amanda G Elgoraish
- Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Salah Eldin G Elzaki
- Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Rania TagElsir Ahmed
- Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Arwa Ibrahim Ahmed
- Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Huda A Fadlalmula
- Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Shymaa Abdalgader Mohamed
- Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
- Department of Zoology, Faculty of Sciences, University of Khartoum, Khartoum, Sudan
| | - Nusiba I Abdallah
- Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
- National University Research Institute, National University, Khartoum, Sudan
| | - Osman Abdelgadir
- Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
- Department of Parasitology and Medical Entomology, Faculty of Medicine and Health Science, University of Kordofan, Elobeid, Sudan
| | - Tellal B Ageep
- Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Badria B El-Sayed
- Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| |
Collapse
|
19
|
Laneri K, Cabella B, Prado PI, Mendes Coutinho R, Kraenkel RA. Climate drivers of malaria at its southern fringe in the Americas. PLoS One 2019; 14:e0219249. [PMID: 31291316 PMCID: PMC6619762 DOI: 10.1371/journal.pone.0219249] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 06/19/2019] [Indexed: 01/01/2023] Open
Abstract
In this work we analyze potential environmental drivers of malaria cases in Northwestern Argentina. We inspect causal links between malaria and climatic variables by means of the convergent cross mapping technique, which provides a causality criterion from the theory of dynamic systems. Analysis is based on 12 years of weekly malaria P. vivax cases in Tartagal, Salta, Argentina-at the southern fringe of malaria incidence in the Americas-together with humidity and temperature time-series spanning the same period. Our results show that there are causal links between malaria cases and both maximum temperature, with a delay of five weeks, and minimum temperature, with delays of zero and twenty two weeks. Humidity is also a driver of malaria cases, with thirteen weeks delay between cause and effect. Furthermore we also determined the sign and strength of the effects. Temperature has always a positive non-linear effect on cases, with maximum temperature effects more pronounced above 25°C and minimum above 17°C, while effects of humidity are more intricate: maximum humidity above 85% has a negative effect, whereas minimum humidity has a positive effect on cases. These results might be signaling processes operating at short (below 5 weeks) and long (over 12 weeks) time delays, corresponding to effects related to parasite cycle and mosquito population dynamics respectively. The non-linearities found for the strength of the effect of temperature on malaria cases make warmer areas more prone to higher increases in the disease incidence. Moreover, our results indicate that an increase of extreme weather events could enhance the risks of malaria spreading and re-emergence beyond the current distribution. Both situations, warmer climate and increase of extreme events, will be remarkably increased by the end of the century in this hot spot of climate change.
Collapse
Affiliation(s)
- Karina Laneri
- Grupo de Física Estadística e Interdisciplinaria, CONICET, Centro Atómico Bariloche, Bariloche, Río Negro, Argentina
- * E-mail:
| | - Brenno Cabella
- Instituto de Física Teórica, Universidade Estadual Paulista - UNESP, São Paulo, SP, Brazil
| | - Paulo Inácio Prado
- LAGE do Departamento de Ecologia, Instituto de Biociências da Universidade de São Paulo, São Paulo, SP, Brazil
| | - Renato Mendes Coutinho
- Centro de Matemática, Computação e Cognição (CMCC), Universidade Federal do ABC, Santo André, SP, Brazil
| | - Roberto André Kraenkel
- Instituto de Física Teórica, Universidade Estadual Paulista - UNESP, São Paulo, SP, Brazil
| |
Collapse
|
20
|
Muller I, Jex AR, Kappe SHI, Mikolajczak SA, Sattabongkot J, Patrapuvich R, Lindner S, Flannery EL, Koepfli C, Ansell B, Lerch A, Emery-Corbin SJ, Charnaud S, Smith J, Merrienne N, Swearingen KE, Moritz RL, Petter M, Duffy MF, Chuenchob V. Transcriptome and histone epigenome of Plasmodium vivax salivary-gland sporozoites point to tight regulatory control and mechanisms for liver-stage differentiation in relapsing malaria. Int J Parasitol 2019; 49:501-513. [PMID: 31071319 PMCID: PMC9973533 DOI: 10.1016/j.ijpara.2019.02.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 02/01/2019] [Accepted: 02/07/2019] [Indexed: 01/21/2023]
Abstract
Plasmodium vivax is the key obstacle to malaria elimination in Asia and Latin America, largely attributed to its ability to form resilient hypnozoites (sleeper cells) in the host liver that escape treatment and cause relapsing infections. The decision to form hypnozoites is made early in the liver infection and may already be set in sporozoites prior to invasion. To better understand these early stages of infection, we undertook a comprehensive transcriptomic and histone epigenetic characterization of P. vivax sporozoites. Through comparisons with recently published proteomic data for the P. vivax sporozoite, our study found that although highly transcribed, transcripts associated with functions needed for early infection of the vertebrate host are not detectable as proteins and may be regulated through translational repression. We identified differential transcription between the sporozoite and published transcriptomes of asexual blood stages and mixed versus hypnozoite-enriched liver stages. These comparisons point to multiple layers of transcriptional, post-transcriptional and post-translational control that appear active in sporozoites and to a lesser extent hypnozoites, but are largely absent in replicating liver schizonts or mixed blood stages. We also characterised histone epigenetic modifications in the P. vivax sporozoite and explored their role in regulating transcription. Collectively, these data support the hypothesis that the sporozoite is a tightly programmed stage to infect the human host and identify mechanisms for hypnozoite formation that may be further explored in liver stage models.
Collapse
Affiliation(s)
| | - Ivo Muller
- Population Health and Immunity Division, The Walter and
Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, Victoria,
3052, Australia,Malaria: Parasites & Hosts Unit, Institut Pasteur, 28
Rue de Dr. Roux, 75015, Paris, France,Department of Medical Biology, The University of Melbourne,
Victoria, 3010, Australia
| | - Aaron R. Jex
- Population Health and Immunity Division, The Walter and
Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, Victoria,
3052, Australia,Department of Medical Biology, The University of Melbourne,
Victoria, 3010, Australia,Faculty of Veterinary and Agricultural Sciences, The
University of Melbourne, Corner of Park and Flemington Road, Parkville, Victoria,
3010, Australia
| | - Stefan H. I. Kappe
- Seattle Children’s Research Institute, 307 Westlake
Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Sebastian A. Mikolajczak
- Seattle Children’s Research Institute, 307 Westlake
Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Jetsumon Sattabongkot
- Mahidol Vivax Research Center, Faculty of Tropical
Medicine, Mahidol University, Bangkok 10400, Thailand
| | | | - Scott Lindner
- Department of Biochemistry and Molecular Biology, Center
for Malaria Research, Pennsylvania State University, University Park, PA 16802,
USA
| | - Erika L. Flannery
- Seattle Children’s Research Institute, 307 Westlake
Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Cristian Koepfli
- Population Health and Immunity Division, The Walter and
Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, Victoria,
3052, Australia
| | - Brendan Ansell
- Faculty of Veterinary and Agricultural Sciences, The
University of Melbourne, Corner of Park and Flemington Road, Parkville, Victoria,
3010, Australia
| | - Anita Lerch
- Population Health and Immunity Division, The Walter and
Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, Victoria,
3052, Australia
| | - Samantha J Emery-Corbin
- Population Health and Immunity Division, The Walter and
Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, Victoria,
3052, Australia
| | - Sarah Charnaud
- Population Health and Immunity Division, The Walter and
Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, Victoria,
3052, Australia
| | - Jeffrey Smith
- Population Health and Immunity Division, The Walter and
Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, Victoria,
3052, Australia
| | - Nicolas Merrienne
- Malaria: Parasites & Hosts Unit, Institut Pasteur, 28
Rue de Dr. Roux, 75015, Paris, France
| | | | | | - Michaela Petter
- Department of Medicine Royal Melbourne Hospital, The Peter
Doherty Institute, The University of Melbourne, 792 Elizabeth Street, Melbourne,
Victoria 3000, Australia,Institute of Microbiology, University Hospital Erlangen,
Erlangen 91054, Germany
| | - Michael F. Duffy
- Department of Medicine Royal Melbourne Hospital, The Peter
Doherty Institute, The University of Melbourne, 792 Elizabeth Street, Melbourne,
Victoria 3000, Australia
| | - Vorada Chuenchob
- Seattle Children’s Research Institute, 307 Westlake
Avenue North, Suite 500, Seattle, WA 98109, USA
| |
Collapse
|
21
|
Malaria morbidity and mortality following introduction of a universal policy of artemisinin-based treatment for malaria in Papua, Indonesia: A longitudinal surveillance study. PLoS Med 2019; 16:e1002815. [PMID: 31167228 PMCID: PMC6541239 DOI: 10.1371/journal.pmed.1002815] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 04/30/2019] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Malaria control activities can have a disproportionately greater impact on Plasmodium falciparum than on P. vivax in areas where both species are coendemic. We investigated temporal trends in malaria-related morbidity and mortality in Papua, Indonesia, before and after introduction of a universal, artemisinin-based antimalarial treatment strategy for all Plasmodium species. METHODS AND FINDINGS A prospective, district-wide malariometric surveillance system was established in April 2004 to record all cases of malaria at community clinics and the regional hospital and maintained until December 2013. In March 2006, antimalarial treatment policy was changed to artemisinin combination therapy for uncomplicated malaria and intravenous artesunate for severe malaria due to any Plasmodium species. Over the study period, a total of 418,238 patients presented to the surveillance facilities with malaria. The proportion of patients with malaria requiring admission to hospital fell from 26.9% (7,745/28,789) in the pre-policy change period (April 2004 to March 2006) to 14.0% (4,786/34,117) in the late transition period (April 2008 to December 2009), a difference of -12.9% (95% confidence interval [CI] -13.5% to -12.2%). There was a significant fall in the mortality of patients presenting to the hospital with P. falciparum malaria (0.53% [100/18,965] versus 0.32% [57/17,691]; difference = -0.21% [95% CI -0.34 to -0.07]) but not in patients with P. vivax malaria (0.28% [21/7,545] versus 0.23% [28/12,397]; difference = -0.05% [95% CI -0.20 to 0.09]). Between the same periods, the overall proportion of malaria due to P. vivax rose from 44.1% (30,444/69,098) to 53.3% (29,934/56,125) in the community clinics and from 32.4% (9,325/28,789) to 44.1% (15,035/34,117) at the hospital. After controlling for population growth and changes in treatment-seeking behaviour, the incidence of P. falciparum malaria fell from 511 to 249 per 1,000 person-years (py) (incidence rate ratio [IRR] = 0.49 [95% CI 0.48-0.49]), whereas the incidence of P. vivax malaria fell from 331 to 239 per 1,000 py (IRR = 0.72 [95% CI 0.71-0.73]). The main limitations of our study were possible confounding from changes in healthcare provision, a growing population, and significant shifts in treatment-seeking behaviour following implementation of a new antimalarial policy. CONCLUSIONS In this area with high levels of antimalarial drug resistance, adoption of a universal policy of efficacious artemisinin-based therapy for malaria infections due to any Plasmodium species was associated with a significant reduction in total malaria-attributable morbidity and mortality. The burden of P. falciparum malaria was reduced to a greater extent than that of P. vivax malaria. In coendemic regions, the timely elimination of malaria will require that safe and effective radical cure of both the blood and liver stages of the parasite is widely available for all patients at risk of malaria.
Collapse
|
22
|
Auburn S, Benavente ED, Miotto O, Pearson RD, Amato R, Grigg MJ, Barber BE, William T, Handayuni I, Marfurt J, Trimarsanto H, Noviyanti R, Sriprawat K, Nosten F, Campino S, Clark TG, Anstey NM, Kwiatkowski DP, Price RN. Genomic analysis of a pre-elimination Malaysian Plasmodium vivax population reveals selective pressures and changing transmission dynamics. Nat Commun 2018; 9:2585. [PMID: 29968722 PMCID: PMC6030216 DOI: 10.1038/s41467-018-04965-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 06/01/2018] [Indexed: 01/13/2023] Open
Abstract
The incidence of Plasmodium vivax infection has declined markedly in Malaysia over the past decade despite evidence of high-grade chloroquine resistance. Here we investigate the genetic changes in a P. vivax population approaching elimination in 51 isolates from Sabah, Malaysia and compare these with data from 104 isolates from Thailand and 104 isolates from Indonesia. Sabah displays extensive population structure, mirroring that previously seen with the emergence of artemisinin-resistant P. falciparum founder populations in Cambodia. Fifty-four percent of the Sabah isolates have identical genomes, consistent with a rapid clonal expansion. Across Sabah, there is a high prevalence of loci known to be associated with antimalarial drug resistance. Measures of differentiation between the three countries reveal several gene regions under putative selection in Sabah. Our findings highlight important factors pertinent to parasite resurgence and molecular cues that can be used to monitor low-endemic populations at the end stages of P. vivax elimination.
Collapse
Affiliation(s)
- Sarah Auburn
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT 0811 Australia ,Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Old Road Campus, Oxford, OX3 7LF UK
| | - Ernest D. Benavente
- 0000 0004 0425 469Xgrid.8991.9Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT UK
| | - Olivo Miotto
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Old Road Campus, Oxford, OX3 7LF UK ,0000 0004 0606 5382grid.10306.34Wellcome Trust Sanger Institute, Hinxton Cambridge, CB10 1SA UK ,0000 0004 1937 0490grid.10223.32Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, 10400 Thailand
| | - Richard D. Pearson
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Old Road Campus, Oxford, OX3 7LF UK ,0000 0004 0606 5382grid.10306.34Wellcome Trust Sanger Institute, Hinxton Cambridge, CB10 1SA UK
| | - Roberto Amato
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Old Road Campus, Oxford, OX3 7LF UK ,0000 0004 0606 5382grid.10306.34Wellcome Trust Sanger Institute, Hinxton Cambridge, CB10 1SA UK
| | - Matthew J. Grigg
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT 0811 Australia ,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, 88300 Kota Kinabalu Sabah, Malaysia
| | - Bridget E. Barber
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT 0811 Australia ,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, 88300 Kota Kinabalu Sabah, Malaysia
| | - Timothy William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, 88300 Kota Kinabalu Sabah, Malaysia ,0000 0004 1772 8727grid.415560.3Clinical Research Centre, Queen Elizabeth Hospital, 88300 Kota Kinabalu Sabah, Malaysia ,Jesselton Medical Centre, 88300 Kota Kinabalu Sabah, Malaysia
| | - Irene Handayuni
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT 0811 Australia
| | - Jutta Marfurt
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT 0811 Australia
| | - Hidayat Trimarsanto
- 0000 0004 1795 0993grid.418754.bEijkman Institute for Molecular Biology, Jakarta, 10430 Indonesia ,0000 0001 0746 0534grid.432292.cAgency for Assessment and Application of Technology, Jl. MH Thamrin 8, Jakarta, 10340 Indonesia
| | - Rintis Noviyanti
- 0000 0004 1795 0993grid.418754.bEijkman Institute for Molecular Biology, Jakarta, 10430 Indonesia
| | - Kanlaya Sriprawat
- 0000 0004 1937 0490grid.10223.32Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot Tak, 63110 Thailand
| | - Francois Nosten
- 0000 0004 1937 0490grid.10223.32Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot Tak, 63110 Thailand ,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine Research Building, University of Oxford Old Road Campus, Oxford, OX3 7LJ UK
| | - Susana Campino
- 0000 0004 0425 469Xgrid.8991.9Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT UK
| | - Taane G. Clark
- 0000 0004 0425 469Xgrid.8991.9Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT UK ,0000 0004 0425 469Xgrid.8991.9Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT UK
| | - Nicholas M. Anstey
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT 0811 Australia
| | - Dominic P. Kwiatkowski
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Old Road Campus, Oxford, OX3 7LF UK ,0000 0004 0606 5382grid.10306.34Wellcome Trust Sanger Institute, Hinxton Cambridge, CB10 1SA UK
| | - Ric N. Price
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT 0811 Australia ,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine Research Building, University of Oxford Old Road Campus, Oxford, OX3 7LJ UK
| |
Collapse
|
23
|
Lover AA, Baird JK, Gosling R, Price RN. Malaria Elimination: Time to Target All Species. Am J Trop Med Hyg 2018; 99:17-23. [PMID: 29761762 PMCID: PMC6035869 DOI: 10.4269/ajtmh.17-0869] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 03/14/2018] [Indexed: 01/13/2023] Open
Abstract
Important strides have been made within the past decade toward malaria elimination in many regions, and with this progress, the feasibility of eradication is once again under discussion. If the ambitious goal of eradication is to be achieved by 2040, all species of Plasmodium infecting humans will need to be targeted with evidence-based and concerted interventions. In this perspective, the potential barriers to achieving global malaria elimination are discussed with respect to the related diversities in host, parasite, and vector populations. We argue that control strategies need to be reorientated from a sequential attack on each species, dominated by Plasmodium falciparum to one that targets all species in parallel. A set of research themes is proposed to mitigate the potential setbacks on the pathway to a malaria-free world.
Collapse
Affiliation(s)
- Andrew A. Lover
- Malaria Elimination Initiative at the University of California, San Francisco, San Francisco, California
| | - J. Kevin Baird
- Eijkman-Oxford Clinical Research Unit, Eijkman Institute of Molecular Biology, Jakarta, Indonesia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Roly Gosling
- Malaria Elimination Initiative at the University of California, San Francisco, San Francisco, California
| | - Ric N. Price
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| |
Collapse
|
24
|
Mbenda HGN, Zeng W, Bai Y, Siddiqui FA, Yang Z, Cui L. Genetic diversity of the Plasmodium vivax phosphatidylinositol 3-kinase gene in two regions of the China-Myanmar border. INFECTION GENETICS AND EVOLUTION 2018; 61:45-52. [PMID: 29462718 DOI: 10.1016/j.meegid.2018.02.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 02/12/2018] [Accepted: 02/14/2018] [Indexed: 12/25/2022]
Abstract
Artemisinin resistance in Plasmodium falciparum was associated with mutations in the propeller domain of the PfK13 gene and increased phosphatidylinositol-3'-kinase (PfPI3K) activity. Assessment of the genetic diversity of the PfK13 ortholog PvK12 in Plasmodium vivax field samples from the same hotspots of P. falciparum artemisinin resistance revealed a limited genetic diversity of PvK12. Following the same logic, we analyzed genetic variations of the PvPI3K gene in 188 P. vivax field isolates from two geographic locations along the China-Myanmar border. Overall, high genetic diversity of PvPI3K was observed; parasites from Yunnan's Tengchong County had higher genetic diversity than those from Laiza Township, Kachin State, Myanmar. Almost all the neutrality tests applied detected statistically significant deviation from zero. The negative Tajima's D values in both populations implicated that PvPI3K gene might have experienced either a directional selection or an expansion in population size. There was low linkage disequilibrium between the PvPI3K mutations in both populations, suggesting the existence of large, almost panmictic, parasite populations that enabled effective recombination. This later result was confirmed by the detection of a minimum of five recombination events in each population with two major breakpoints. Multiple tests for selection confirmed a signature of purifying selection on PvPI3K. All the amino acid mutations were predicted to be neutral for the PI3K protein's function. These findings provide insights on the genetic diversity of P. vivax populations along the China-Myanmar border.
Collapse
Affiliation(s)
| | - Weilin Zeng
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Yao Bai
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Faiza Amber Siddiqui
- Department of Entomology, Pennsylvania State University, 501 ASI Building, University Park, PA 16802, USA
| | - Zhaoqing Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China.
| | - Liwang Cui
- Department of Entomology, Pennsylvania State University, 501 ASI Building, University Park, PA 16802, USA.
| |
Collapse
|
25
|
Patankar S, Sharma S, Rathod PK, Duraisingh MT. Malaria in India: The Need for New Targets for Diagnosis and Detection of Plasmodium vivax. Proteomics Clin Appl 2018; 12:e1700024. [PMID: 29193853 DOI: 10.1002/prca.201700024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 08/28/2017] [Indexed: 11/08/2022]
Abstract
Plasmodium vivax is a protozoan parasite that is one of the causative agents of human malaria. Due to several occult features of its life cycle, P. vivax threatens to be a problem for the recent efforts toward elimination of malaria globally. With an emphasis on malaria elimination goals, the authors summarize the major gaps in P. vivax diagnosis and describe how proteomics technologies have begun to contribute toward the discovery of antigens that could be used for various technology platforms and applications. The authors suggest areas where, in the future, proteomics technologies could fill in gaps in P. vivax diagnosis that have proved difficult. The discovery of new parasite antigens, host responses, and immune signatures using proteomics technologies will be a key part of the global malaria elimination efforts.
Collapse
Affiliation(s)
- Swati Patankar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India.,Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Shobhona Sharma
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | | | - Manoj T Duraisingh
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| |
Collapse
|
26
|
Carrasco-Escobar G, Miranda-Alban J, Fernandez-Miñope C, Brouwer KC, Torres K, Calderon M, Gamboa D, Llanos-Cuentas A, Vinetz JM. High prevalence of very-low Plasmodium falciparum and Plasmodium vivax parasitaemia carriers in the Peruvian Amazon: insights into local and occupational mobility-related transmission. Malar J 2017; 16:415. [PMID: 29037202 PMCID: PMC5644076 DOI: 10.1186/s12936-017-2063-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 10/11/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The incidence of malaria due both to Plasmodium falciparum and Plasmodium vivax in the Peruvian Amazon has risen in the past 5 years. This study tested the hypothesis that the maintenance and emergence of malaria in hypoendemic regions such as Amazonia is determined by submicroscopic and asymptomatic Plasmodium parasitaemia carriers. The present study aimed to precisely quantify the rate of very-low parasitaemia carriers in two sites of the Peruvian Amazon in relation to transmission patterns of P. vivax and P. falciparum in this area. METHODS This study was carried out within the Amazonian-ICEMR longitudinal cohort. Blood samples were collected for light microscopy diagnosis and packed red blood cell (PRBC) samples were analysed by qPCR. Plasma samples were tested for total IgG reactivity against recombinant PvMSP-10 and PfMSP-10 antigens by ELISA. Occupation and age 10 years and greater were considered surrogates of occupation-related mobility. Risk factors for P. falciparum and P. vivax infections detected by PRBC-qPCR were assessed by multilevel logistic regression models. RESULTS Among 450 subjects, the prevalence of P. vivax by PRBC-PCR (25.1%) was sixfold higher than that determined by microscopy (3.6%). The prevalence of P. falciparum infection was 4.9% by PRBC-PCR and 0.2% by microscopy. More than 40% of infections had parasitaemia under 5 parasites/μL. Multivariate analysis for infections detected by PRBC-PCR showed that participants with recent settlement in the study area (AOR 2.1; 95% CI 1.03:4.2), age ≥ 30 years (AOR 3.3; 95% CI 1.6:6.9) and seropositivity to P. vivax (AOR 1.8; 95% CI 1.0:3.2) had significantly higher likelihood of P. vivax infection, while the odds of P. falciparum infection was higher for participants between 10 and 29 years (AOR 10.7; 95% CI 1.3:91.1) and with a previous P. falciparum infection (AOR 10.4; 95% CI 1.5:71.1). CONCLUSIONS This study confirms the contrasting transmission patterns of P. vivax and P. falciparum in the Peruvian Amazon, with stable local transmission for P. vivax and the source of P. falciparum to the study villages dominated by very low parasitaemia carriers, age 10 years and older, who had travelled away from home for work and brought P. falciparum infection with them.
Collapse
Affiliation(s)
- Gabriel Carrasco-Escobar
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru. .,Facultad de Salud Pública, Universidad Peruana Cayetano Heredia, Lima, Peru.
| | - Julio Miranda-Alban
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Carlos Fernandez-Miñope
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Kimberly C Brouwer
- Division of Epidemiology, Department of Family Medicine & Public Health, University of California, San Diego, La Jolla, CA, USA
| | - Katherine Torres
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru.,Departamento de Ciencias Celulares y Moleculares, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Maritza Calderon
- Departamento de Ciencias Celulares y Moleculares, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Dionicia Gamboa
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru.,Departamento de Ciencias Celulares y Moleculares, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru.,Instituto de Medicinal Tropical "Alexander von Humboldt", Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Alejandro Llanos-Cuentas
- Facultad de Salud Pública, Universidad Peruana Cayetano Heredia, Lima, Peru.,Instituto de Medicinal Tropical "Alexander von Humboldt", Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Joseph M Vinetz
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru. .,Departamento de Ciencias Celulares y Moleculares, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru. .,Instituto de Medicinal Tropical "Alexander von Humboldt", Universidad Peruana Cayetano Heredia, Lima, Peru. .,Division of Infectious Diseases, Department of Medicine, University of California, San Diego, 9500 Gilman Drive MC0760, Biomedical Research Facility-2, Room 4A16, La Jolla, CA, USA.
| |
Collapse
|
27
|
Longley RJ, França CT, White MT, Kumpitak C, Sa-Angchai P, Gruszczyk J, Hostetler JB, Yadava A, King CL, Fairhurst RM, Rayner JC, Tham WH, Nguitragool W, Sattabongkot J, Mueller I. Asymptomatic Plasmodium vivax infections induce robust IgG responses to multiple blood-stage proteins in a low-transmission region of western Thailand. Malar J 2017; 16:178. [PMID: 28454546 PMCID: PMC5410030 DOI: 10.1186/s12936-017-1826-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Accepted: 04/19/2017] [Indexed: 11/11/2022] Open
Abstract
Background Thailand is aiming to eliminate malaria by the year 2024. Plasmodium vivax has now become the dominant species causing malaria within the country, and a high proportion of infections are asymptomatic. A better understanding of antibody dynamics to P. vivax antigens in a low-transmission setting, where acquired immune responses are poorly characterized, will be pivotal for developing new strategies for elimination, such as improved surveillance methods and vaccines. The objective of this study was to characterize total IgG antibody levels to 11 key P. vivax proteins in a village of western Thailand. Methods Plasma samples from 546 volunteers enrolled in a cross-sectional survey conducted in 2012 in Kanchanaburi Province were utilized. Total IgG levels to 11 different proteins known or predicted to be involved in reticulocyte binding or invasion (ARP, GAMA, P41, P12, PVX_081550, and five members of the PvRBP family), as well as the leading pre-erythrocytic vaccine candidate (CSP) were measured using a multiplexed bead-based assay. Associations between IgG levels and infection status, age, and spatial location were explored. Results Individuals from a low-transmission region of western Thailand reacted to all 11 P. vivax recombinant proteins. Significantly greater IgG levels were observed in the presence of a current P. vivax infection, despite all infected individuals being asymptomatic. IgG levels were also higher in adults (18 years and older) than in children. For most of the proteins, higher IgG levels were observed in individuals living closer to the Myanmar border and further away from local health services. Conclusions Robust IgG responses were observed to most proteins and IgG levels correlated with surrogates of exposure, suggesting these antigens may serve as potential biomarkers of exposure, immunity, or both. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1826-8) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Rhea J Longley
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Camila T França
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Michael T White
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Imperial College, London, UK
| | - Chalermpon Kumpitak
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Patiwat Sa-Angchai
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Jakub Gruszczyk
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Jessica B Hostetler
- Malaria Programme, Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, UK.,Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Anjali Yadava
- Malaria Vaccine Branch, United States Military Malaria Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Christopher L King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
| | - Rick M Fairhurst
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Julian C Rayner
- Malaria Programme, Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, UK
| | - Wai-Hong Tham
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Wang Nguitragool
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Jetsumon Sattabongkot
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Ivo Mueller
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia. .,Department of Medical Biology, University of Melbourne, Melbourne, Australia. .,ISGlobal, Barcelona Institute for Global Health, Hospital Clínic-Universitat de Barcelona, 08036, Barcelona, Spain. .,Institut Pasteur, Paris, France.
| |
Collapse
|
28
|
Howes RE, Battle KE, Mendis KN, Smith DL, Cibulskis RE, Baird JK, Hay SI. Global Epidemiology of Plasmodium vivax. Am J Trop Med Hyg 2016; 95:15-34. [PMID: 27402513 PMCID: PMC5198891 DOI: 10.4269/ajtmh.16-0141] [Citation(s) in RCA: 253] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 04/19/2016] [Indexed: 01/09/2023] Open
Abstract
Plasmodium vivax is the most widespread human malaria, putting 2.5 billion people at risk of infection. Its unique biological and epidemiological characteristics pose challenges to control strategies that have been principally targeted against Plasmodium falciparum Unlike P. falciparum, P. vivax infections have typically low blood-stage parasitemia with gametocytes emerging before illness manifests, and dormant liver stages causing relapses. These traits affect both its geographic distribution and transmission patterns. Asymptomatic infections, high-risk groups, and resulting case burdens are described in this review. Despite relatively low prevalence measurements and parasitemia levels, along with high proportions of asymptomatic cases, this parasite is not benign. Plasmodium vivax can be associated with severe and even fatal illness. Spreading resistance to chloroquine against the acute attack, and the operational inadequacy of primaquine against the multiple attacks of relapse, exacerbates the risk of poor outcomes among the tens of millions suffering from infection each year. Without strategies accounting for these P. vivax-specific characteristics, progress toward elimination of endemic malaria transmission will be substantially impeded.
Collapse
Affiliation(s)
- Rosalind E. Howes
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Katherine E. Battle
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Kamini N. Mendis
- Global Malaria Program, World Health Organization, Geneva, Switzerland
| | - David L. Smith
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland
- Sanaria Institute for Global Health and Tropical Medicine, Rockville, Maryland
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, Washington
| | | | - J. Kevin Baird
- Eijkman-Oxford Clinical Research Unit, Jakarta, Indonesia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Simon I. Hay
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, Washington
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, United Kingdom
| |
Collapse
|
29
|
White MT, Yeung S, Patouillard E, Cibulskis R. Costs and Cost-Effectiveness of Plasmodium vivax Control. Am J Trop Med Hyg 2016; 95:52-61. [PMID: 28025283 PMCID: PMC5201223 DOI: 10.4269/ajtmh.16-0182] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 06/03/2016] [Indexed: 01/12/2023] Open
Abstract
The continued success of efforts to reduce the global malaria burden will require sustained funding for interventions specifically targeting Plasmodium vivax The optimal use of limited financial resources necessitates cost and cost-effectiveness analyses of strategies for diagnosing and treating P. vivax and vector control tools. Herein, we review the existing published evidence on the costs and cost-effectiveness of interventions for controlling P. vivax, identifying nine studies focused on diagnosis and treatment and seven studies focused on vector control. Although many of the results from the much more extensive P. falciparum literature can be applied to P. vivax, it is not always possible to extrapolate results from P. falciparum-specific cost-effectiveness analyses. Notably, there is a need for additional studies to evaluate the potential cost-effectiveness of radical cure with primaquine for the prevention of P. vivax relapses with glucose-6-phosphate dehydrogenase testing.
Collapse
Affiliation(s)
- Michael T. White
- MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Shunmay Yeung
- Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Edith Patouillard
- Global Malaria Programme, World Health Organization, Geneva, Switzerland
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- Universität Basel, Basel, Switzerland
| | - Richard Cibulskis
- Global Malaria Programme, World Health Organization, Geneva, Switzerland
| |
Collapse
|
30
|
Fontoura PS, Finco BF, Lima NF, de Carvalho JF, Vinetz JM, Castro MC, Ferreira MU. Reactive Case Detection for Plasmodium vivax Malaria Elimination in Rural Amazonia. PLoS Negl Trop Dis 2016; 10:e0005221. [PMID: 27941968 PMCID: PMC5179126 DOI: 10.1371/journal.pntd.0005221] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 12/22/2016] [Accepted: 12/01/2016] [Indexed: 12/31/2022] Open
Abstract
Background Malaria burden in Brazil has reached its lowest levels in 35 years and Plasmodium vivax now accounts for 84% of cases countrywide. Targeting residual malaria transmission entrenched in the Amazon is the next major challenge for ongoing elimination efforts. Better strategies are urgently needed to address the vast reservoir of asymptomatic P. vivax carriers in this and other areas approaching malaria elimination. Methods We evaluated a reactive case detection (RCD) strategy tailored for P. vivax transmission in farming settlements in the Amazon Basin of Brazil. Over six months, 41 cases detected by passive surveillance triggered four rounds of RCD (0, 30, 60, and 180 days after index case enrollment), using microscopy- and quantitative real-time polymerase chain reaction (qPCR)-based diagnosis, comprising subjects sharing the household (HH) with the index case (n = 163), those living in the 5 nearest HHs within 3 km (n = 878), and individuals from 5 randomly chosen control HHs located > 5 km away from index cases (n = 841). Correlates of infection were identified with mixed-effects logistic regression models. Molecular genotyping was used to infer local parasite transmission networks. Principal findings/Conclusions Subjects in index and neighbor HHs were significantly more likely to be parasitemic than control HH members, after adjusting for potential confounders, and together harbored > 90% of the P. vivax biomass in study subjects. Clustering patterns were temporally stable. Four rounds of microscopy-based RCD would identify only 49.5% of the infections diagnosed by qPCR, but 76.8% of the total parasite biomass circulating in the proximity of index HHs. However, control HHs accounted for 27.6% of qPCR-positive samples, 92.6% of them from asymptomatic carriers beyond the reach of RCD. Molecular genotyping revealed high P. vivax diversity, consistent with complex transmission networks and multiple sources of infection within clusters, potentially complicating malaria elimination efforts. Addressing the vast reservoir of asymptomatic Plasmodium vivax carriers clustered in hard-to-reach rural communities is a major challenge faced by countries approaching malaria elimination across Latin America and Asia. Routine surveillance targets subjects presenting with fever or reporting recent fever, but overlooks asymptomatic infections that might be otherwise detected by periodic mass blood surveys of the entire population at risk. Here we show that subjects living in close proximity to malaria cases detected by routine passive surveillance are much more likely to carry both symptomatic and asymptomatic infections than randomly selected inhabitants in the same farming settlements in the Amazon Basin of Brazil. Four rounds of microscopy-based screening for malaria parasites targeted at these high-risk subjects would identify 49.5% of the parasite carriers (who together harbored 76.8% of the total P. vivax biomass circulating in the proximity of index cases) detected by a more sensitive molecular method. Whether subpatent and asymptomatic carriers outside the identified clusters of symptomatic infections, beyond the reach of our screening, represent a significant parasite reservoir remains undetermined. The extensive genetic diversity found in local P. vivax populations suggests that multiple sources of infection fuel ongoing residual transmission within malaria clusters, further complicating current elimination efforts.
Collapse
Affiliation(s)
- Pablo S. Fontoura
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Bruna F. Finco
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Nathália F. Lima
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Jaques F. de Carvalho
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Joseph M. Vinetz
- Division of Infectious Diseases, Department of Medicine, University of California San Diego, La Jolla, CA, United States of America
- Alexander von Humboldt Institute of Tropical Medicine and Faculty of Sciences, Department of Cellular and Molecular Sciences, Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Márcia C. Castro
- Department of Global Health and Population, Harvard T. H. Chan School of Public Health, Boston, MA, United States of America
| | - Marcelo U. Ferreira
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
- * E-mail:
| |
Collapse
|
31
|
Santos-Vega M, Bouma MJ, Kohli V, Pascual M. Population Density, Climate Variables and Poverty Synergistically Structure Spatial Risk in Urban Malaria in India. PLoS Negl Trop Dis 2016; 10:e0005155. [PMID: 27906962 PMCID: PMC5131912 DOI: 10.1371/journal.pntd.0005155] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 11/02/2016] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND The world is rapidly becoming urban with the global population living in cities projected to double by 2050. This increase in urbanization poses new challenges for the spread and control of communicable diseases such as malaria. In particular, urban environments create highly heterogeneous socio-economic and environmental conditions that can affect the transmission of vector-borne diseases dependent on human water storage and waste water management. Interestingly India, as opposed to Africa, harbors a mosquito vector, Anopheles stephensi, which thrives in the man-made environments of cities and acts as the vector for both Plasmodium vivax and Plasmodium falciparum, making the malaria problem a truly urban phenomenon. Here we address the role and determinants of within-city spatial heterogeneity in the incidence patterns of vivax malaria, and then draw comparisons with results for falciparum malaria. METHODOLOGY/PRINCIPAL FINDINGS Statistical analyses and a phenomenological transmission model are applied to an extensive spatio-temporal dataset on cases of Plasmodium vivax in the city of Ahmedabad (Gujarat, India) that spans 12 years monthly at the level of wards. A spatial pattern in malaria incidence is described that is largely stationary in time for this parasite. Malaria risk is then shown to be associated with socioeconomic indicators and environmental parameters, temperature and humidity. In a more dynamical perspective, an Inhomogeneous Markov Chain Model is used to predict vivax malaria risk. Models that account for climate factors, socioeconomic level and population size show the highest predictive skill. A comparison to the transmission dynamics of falciparum malaria reinforces the conclusion that the spatio-temporal patterns of risk are strongly driven by extrinsic factors. CONCLUSION/SIGNIFICANCE Climate forcing and socio-economic heterogeneity act synergistically at local scales on the population dynamics of urban malaria in this city. The stationarity of malaria risk patterns provides a basis for more targeted intervention, such as vector control, based on transmission 'hotspots'. This is especially relevant for P. vivax, a more resilient parasite than P. falciparum, due to its ability to relapse and the operational shortcomings of delivering a "radical cure".
Collapse
Affiliation(s)
- Mauricio Santos-Vega
- Department of Ecology and Evolution, University of Chicago, Chicago, United States of America
| | - Menno J Bouma
- London School of Hygiene and Tropical Medicine, University of London, United Kingdom
- Institute for Climate Sciences (IC3), University of Barcelona, Barcelona, Spain
| | - Vijay Kohli
- Ahmedabad Municipal Corporation, Ahmedabad, India
| | - Mercedes Pascual
- Department of Ecology and Evolution, University of Chicago, Chicago, United States of America
| |
Collapse
|
32
|
Deng S, Ruan Y, Bai Y, Hu Y, Deng Z, He Y, Ruan R, Wu Y, Yang Z, Cui L. Genetic diversity of the Pvk12 gene in Plasmodium vivax from the China-Myanmar border area. Malar J 2016; 15:528. [PMID: 27809837 PMCID: PMC5096284 DOI: 10.1186/s12936-016-1592-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 10/28/2016] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Plasmodium falciparum resistance to artemisinin emerged in the Greater Mekong Sub-region has been associated with mutations in the propeller domain of the kelch gene Pfk13. METHODS Here the polymorphisms in Pvk12 gene, the orthologue of Pfk13 in Plasmodium vivax, were determined by PCR and sequencing in 262 clinical isolates collected in recent years (2012-2015) from the China-Myanmar border area. RESULTS Sequencing of full-length Pvk12 genes from these isolates identified three synonymous mutations (N172N, S360S, S697S) and one non-synonymous mutation M124I, all of which were at very low prevalence (2.0-3.1%). Moreover, these mutations were non-overlapping between the two study sites on both sides of the border. Molecular evolutionary analysis detected signature of purifying selection on Pvk12. CONCLUSIONS There is no direct evidence that Pvk12 is involved in artemisinin resistance in P. vivax, but it remains a potential candidate requiring further investigation. Continuous monitoring of potential drug resistance in this parasite is needed in order to facilitate the regional malaria elimination campaign.
Collapse
Affiliation(s)
- Shuang Deng
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan Province, China.,Department of Pathology, Kunming Medical University, Kunming, 650500, Yunnan Province, China
| | - Yonghua Ruan
- Department of Pathology, Kunming Medical University, Kunming, 650500, Yunnan Province, China
| | - Yao Bai
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan Province, China.,Department of Pharmacology, Kunming Medical University, Kunming, 650500, Yunnan Province, China
| | - Yue Hu
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan Province, China.,Department of Pathology, Kunming Medical University, Kunming, 650500, Yunnan Province, China
| | - Zeshuai Deng
- Department of Cell Biology and Medical Genetics, Kunming Medical University, Kunming, 650500, Yunnan Province, China
| | - Yongshu He
- Department of Cell Biology and Medical Genetics, Kunming Medical University, Kunming, 650500, Yunnan Province, China
| | - Rui Ruan
- Department of Orthopedics, The First Affiliated Hospital, Kunming Medical University, Kunming, 650500, Yunnan Province, China
| | - Yanrui Wu
- Department of Cell Biology and Medical Genetics, Kunming Medical University, Kunming, 650500, Yunnan Province, China
| | - Zhaoqing Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan Province, China.
| | - Liwang Cui
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan Province, China.
| |
Collapse
|
33
|
Wangdi K, Gatton ML, Kelly GC, Banwell C, Dev V, Clements ACA. Malaria elimination in India and regional implications. THE LANCET. INFECTIOUS DISEASES 2016; 16:e214-e224. [PMID: 27527748 DOI: 10.1016/s1473-3099(16)30123-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 03/30/2016] [Accepted: 05/05/2016] [Indexed: 12/16/2022]
Abstract
The malaria situation in India is complex as a result of diverse socio-environmental conditions. India contributes a substantial burden of malaria outside sub-Saharan Africa, with the third highest Plasmodium vivax prevalence in the world. Successful malaria control in India is likely to enhance malaria elimination efforts in the region. Despite modest gains, there are many challenges for malaria elimination in India, including: varied patterns of malaria transmission in different parts of the country demanding area-specific control measures; intense malaria transmission fuelled by favourable climatic and environment factors; varying degrees of insecticide resistance of vectors; antimalarial drug resistance; a weak surveillance system; and poor national coordination of state programmes. Prevention and protection against malaria are low as a result of a weak health-care system, as well as financial and socioeconomic constraints. Additionally, the open borders of India provide a potential route of entry for artesunate-resistant parasites from southeast Asia. This situation calls for urgent dialogue around tackling malaria across borders-between India's states and neighbouring countries-through sharing of information and coordinated control and preventive measures, if we are to achieve the aim of malaria elimination in the region.
Collapse
Affiliation(s)
- Kinley Wangdi
- Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, Australia; Phuentsholing General Hospital, Phuentsholing, Bhutan.
| | - Michelle L Gatton
- School of Public Health & Social Work, Queensland University of Technology, Brisbane, QLD, Australia
| | - Gerard C Kelly
- Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, Australia
| | - Cathy Banwell
- Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, Australia
| | - Vas Dev
- National Institute of Malaria Research (ICMR), Guwahati, Assam, India
| | - Archie C A Clements
- Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, Australia
| |
Collapse
|
34
|
Vitor-Silva S, Siqueira AM, de Souza Sampaio V, Guinovart C, Reyes-Lecca RC, de Melo GC, Monteiro WM, Del Portillo HA, Alonso P, Bassat Q, Lacerda MVG. Declining malaria transmission in rural Amazon: changing epidemiology and challenges to achieve elimination. Malar J 2016; 15:266. [PMID: 27165432 PMCID: PMC4863332 DOI: 10.1186/s12936-016-1326-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/03/2016] [Indexed: 01/20/2023] Open
Abstract
Background In recent years, considerable success in reducing its incidence has been achieved in Brazil, leading to a relative increase in the proportion of cases caused by Plasmodium vivax, considered a harder-to-eliminate parasite. This study aim is to describe the transmission dynamics and associated risk factors in a rural settlement area in the Western Brazilian Amazon. Methods A prospective cohort was established in a rural settlement area for 3 years. Follow-up included continuous passive case detection and monthly active case detection for a period of 6 months. Demographic, clinical and transmission control practices data were collected. Malaria diagnosis was performed through thick blood smear. Univariable and multivariable analyses of factors associated with malaria incidence were performed using negative binomial regression models. Factors associated with recurrence of P. vivax and Plasmodium falciparum malaria within 90 days of a previous episode were analysed using univariable and multivariable Cox-Proportional Hazard models. Results Malaria prevalence decreased from 7 % at the study beginning to 0.6 % at month 24, with P. vivax predominating and P. falciparum disappearing after 1 year of follow-up. Malaria incidence was significantly higher in the dry season [IRR (95 % CI) 1.4 (1.1–1.6); p < 0.001)]. Use of ITN was associated to malaria protection in the localities [IRR (95 % CI) 0.7 (0.6–0.8); p = 0.001)]. A recurrent P. vivax episode within 90 days was observed in 29.4 % of individuals after an initial diagnosis. A previous P. vivax [IRR (95 % CI) 2.3 (1.3–4.0); p = 0.006)] or mixed P. vivax + P. falciparum [IRR (95 % CI) 2.9 (1.5–5.7); p = 0.002)] infections were significantly associated to a vivax malaria episode within 90 days of follow-up. Conclusions In an area of P. falciparum and P. vivax co-endemicity, a virtual disappearance of P. falciparum was observed with P. vivax increasing its relative contribution, with a large proportion of recurring episodes. This finding reinforces the perception of P. falciparum being more responsive to early diagnosis and treatment and ITN use and the contribution of relapsing P. vivax to maintain this species’ transmission. In areas of P. vivax endemicity, antihypnozoite treatment effectiveness assessment in different transmission intensity may be a fundamental activity for malaria control and elimination. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1326-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Sheila Vitor-Silva
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil.,Universidade do Estado do Amazonas, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil
| | - André Machado Siqueira
- Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Av. Brasil, 4365, Manguinhos, Rio de Janeiro, RJ, 21040-360, Brazil
| | - Vanderson de Souza Sampaio
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil.,Universidade do Estado do Amazonas, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil
| | - Caterina Guinovart
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Rosselló 132, 4°, 08036, Barcelona, Spain
| | - Roberto Carlos Reyes-Lecca
- Secretaria de Vigilância em Saúde, Ministério da Saúde, Lotes 5/6 Bloco F, SAF Sul Trecho 2, Brasília, DF, 70070-600, Brazil
| | - Gisely Cardoso de Melo
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil.,Universidade do Estado do Amazonas, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil
| | - Wuelton Marcelo Monteiro
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil.,Universidade do Estado do Amazonas, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil
| | - Hernando A Del Portillo
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Rosselló 132, 4°, 08036, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Pedro Alonso
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Rosselló 132, 4°, 08036, Barcelona, Spain
| | - Quique Bassat
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Rosselló 132, 4°, 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Marcus Vinícius Guimarães Lacerda
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil. .,Universidade do Estado do Amazonas, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil. .,Instituto de Pesquisas Leônidas & Maria Deane, Fundação Oswaldo Cruz, Rua Terezina, 476, Adrianópolis, Manaus, AM, 69057-070, Brazil.
| |
Collapse
|
35
|
Gabrielli S, Bellina L, Milardi GL, Katende BK, Totino V, Fullin V, Cancrini G. Malaria in children of Tshimbulu (Western Kasai, Democratic Republic of the Congo): epidemiological data and accuracy of diagnostic assays applied in a limited resource setting. Malar J 2016; 15:81. [PMID: 26864461 PMCID: PMC4750168 DOI: 10.1186/s12936-016-1142-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 02/03/2016] [Indexed: 01/08/2023] Open
Abstract
Background The literature data on malaria in Western Kasai, DRC, are limited and inadequate. A recent molecular survey there has detected Plasmodium ovale and Plasmodium malariae as mixed infections with Plasmodium falciparum. In Tshimbulu, Western Kasai, during a humanitarian initiative designed to provide children with free preventive screening and to reduce the local high malaria death rate, accurate species identification was performed,
in order to collect unambiguous epidemiological data and to evaluate the reliability of locally applied diagnostics. Methods Finger pricks provided fresh blood for microscopic analysis (MA), for rapid diagnostic test (RDT) and for molecular diagnostics (MD). MA and RDT were first performed by the local team and then a re-interpretation of the results (on the same slides and on RDT’s taken pictures) was conducted in Italy, where MD were performed. Results The analysis was conducted on 306 children; RDT found 80.9 % as P. falciparum-positive (37.4 % as two-band positive, P. falciparum single infection). MA identified a further four children as positive to P. falciparum and six co-infections with P. ovale. The second RDT evaluation confirmed a similar infection rate (78.2 %) but interpreted as two-band positive a significantly higher share of tests (56.8 %). MA confirmed 80.0 % of the children as malaria positive and, in addition to P. falciparum, identified P. malariae (13.8 %), P. vivax (3.4 %) and P. ovale (2.4 %), and detected Babesia microti in 19 smears. MD confirmed all of the species found (Babesia microti included), classified as mono-infection with P. falciparum a rate of spots comparable to MA revision, and identified all P. ovale as Plasmodium ovale wallikeri. The RDT used locally proved 93.1 % sensitive and 92.1 % specific for P. falciparum. Conclusions The malaria prevalence among the children and the presence of four Plasmodium species, highlighted in this study, identified a sanitary issue which proved to be more alarming than expected, as it was worsened by the unpredictable presence of P. vivax and Babesia microti (never before reported in DRC). Each diagnostic tool showed its point of weakness. Therefore, the most correct approach is by the combined use of different, locally available, diagnostic tools.
Collapse
Affiliation(s)
- Simona Gabrielli
- Dip. Sanità Pubblica e Malattie infettive, Università "Sapienza", P.le Aldo Moro 5, 00185, Rome, Italy.
| | - Livia Bellina
- MobileDiagnosis Onlus, via Sciuti 180, 90144, Palermo, Italy.
| | - Giovanni Luigi Milardi
- Dip. Sanità Pubblica e Malattie infettive, Università "Sapienza", P.le Aldo Moro 5, 00185, Rome, Italy.
| | | | - Valentina Totino
- Dip. Sanità Pubblica e Malattie infettive, Università "Sapienza", P.le Aldo Moro 5, 00185, Rome, Italy.
| | - Valerio Fullin
- St François Hospital, Tshimbulu, BP 185, Kananga, Western Kasai, Democratic Republic of Congo.
| | - Gabriella Cancrini
- Dip. Sanità Pubblica e Malattie infettive, Università "Sapienza", P.le Aldo Moro 5, 00185, Rome, Italy.
| |
Collapse
|
36
|
Sriwichai P, Karl S, Samung Y, Sumruayphol S, Kiattibutr K, Payakkapol A, Mueller I, Yan G, Cui L, Sattabongkot J. Evaluation of CDC light traps for mosquito surveillance in a malaria endemic area on the Thai-Myanmar border. Parasit Vectors 2015; 8:636. [PMID: 26666683 PMCID: PMC4678759 DOI: 10.1186/s13071-015-1225-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/23/2015] [Indexed: 11/10/2022] Open
Abstract
Background Centers for Disease Control and Prevention miniature light traps (CDC-LT) baited with CO2 are a routine tool for adult mosquito sampling used in entomological surveys, and for monitoring and surveillance of disease vectors. The present study was aimed at evaluating the performance of baited and unbaited CDC-LT for indoor and outdoor trapping of endemic mosquito species in northwestern Thailand. Methods CDC-LT (n = 112) with and without dry ice baits were set both indoors and outdoors in 88 selected houses for stretches of 5 consecutive nights per month in 7 villages in Tha Song Yang district, Tak province between January 2011 and March 2013. Individual traps were repeatedly placed in the same location for a median of 6 (range 1–10) times. Mosquitoes were identified by morphological characteristics and classified into blood-fed, empty, male/female and gravid. Absolute mosquito numbers were converted to capture rates (i.e., mosquitoes per trap and year). Capture rates were compared using multilevel negative binomial regression to account for multiple trap placements and adjust for regional and seasonal differences. Results A total of 6,668 mosquitoes from 9 genera were collected from 576 individual CDC-LT placements. Culex was the predominant captured genus (46 %), followed by anopheline mosquitoes (45 %). Overall, CO2 baited traps captured significantly more Culex (especially Culex vishnui Theobald) and Anopheles mosquitoes per unit time (adjusted capture rate ratio (aCRR) 1.64 and 1.38, respectively). Armigeres spp. mosquitoes were trapped in outdoor traps with significantly higher frequency (aCRR: 1.50), whereas Aedes albopictus (Skuse) had a tendency to be trapped more frequently indoors (aCRR: 1.89, p = 0.07). Furthermore, capture rate ratios between CO2 baited and non-baited CDC-LT were significantly influenced by seasonality and indoor vs. outdoor trap placement. Conclusion The present study shows that CDC-LT with CO2 baiting capture significantly more Culex and Anopheles mosquitoes, some of which (e.g., Cx. vishnui, Cx. quinquefasciatus Say, An. minimus s.l. Theobald, An. maculatus s.l. Theobald) represent important disease vectors in Thailand. This study also shows significant differences in the capture efficiency of CDC-LT when placed indoors or outdoors and in different seasons. Our study thus provides important guidelines for more targeted future vector trapping studies on the Thai-Myanmar border, which is an important cross-border malaria transmission region in Thailand. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-1225-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Patchara Sriwichai
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Stephan Karl
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.
| | - Yudthana Samung
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Suchada Sumruayphol
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Kirakorn Kiattibutr
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Anon Payakkapol
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.
| | - Guiyun Yan
- Program in Public Health, University of California, Irvine, CA, USA.
| | - Liwang Cui
- Department of Entomology, Pennsylvania State University, University Park, PA, USA.
| | - Jetsumon Sattabongkot
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| |
Collapse
|
37
|
Talundzic E, Chenet SM, Goldman IF, Patel DS, Nelson JA, Plucinski MM, Barnwell JW, Udhayakumar V. Genetic Analysis and Species Specific Amplification of the Artemisinin Resistance-Associated Kelch Propeller Domain in P. falciparum and P. vivax. PLoS One 2015; 10:e0136099. [PMID: 26292024 PMCID: PMC4546394 DOI: 10.1371/journal.pone.0136099] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 07/29/2015] [Indexed: 11/19/2022] Open
Abstract
Plasmodium falciparum resistance to artemisinin has emerged in the Greater Mekong Subregion and now poses a threat to malaria control and prevention. Recent work has identified mutations in the kelch propeller domain of the P. falciparum K13 gene to be associated artemisinin resistance as defined by delayed parasite clearance and ex vivo ring stage survival assays. Species specific primers for the two most prevalent human malaria species, P. falciparum and P. vivax, were designed and tested on multiple parasite isolates including human, rodent, and non- humans primate Plasmodium species. The new protocol described here using the species specific primers only amplified their respective species, P. falciparum and P. vivax, and did not cross react with any of the other human malaria Plasmodium species. We provide an improved species specific PCR and sequencing protocol that could be effectively used in areas where both P. falciparum and P. vivax are circulating. To design this improved protocol, the kelch gene was analyzed and compared among different species of Plasmodium. The kelch propeller domain was found to be highly conserved across the mammalian Plasmodium species.
Collapse
Affiliation(s)
- Eldin Talundzic
- Centers for Disease Control and Prevention, Center for Global Health, Division of Parasitic Diseases and Malaria, 1600 Clifton Rd, Mail Stop D-67, Atlanta, Georgia, United States of America
- Atlanta Research and Education Foundation/VA Medical Center, Decatur, Georgia, United States of America
- * E-mail:
| | - Stella M. Chenet
- Centers for Disease Control and Prevention, Center for Global Health, Division of Parasitic Diseases and Malaria, 1600 Clifton Rd, Mail Stop D-67, Atlanta, Georgia, United States of America
| | - Ira F. Goldman
- Centers for Disease Control and Prevention, Center for Global Health, Division of Parasitic Diseases and Malaria, 1600 Clifton Rd, Mail Stop D-67, Atlanta, Georgia, United States of America
| | - Dhruviben S. Patel
- Centers for Disease Control and Prevention, Center for Global Health, Division of Parasitic Diseases and Malaria, 1600 Clifton Rd, Mail Stop D-67, Atlanta, Georgia, United States of America
| | - Julia A. Nelson
- Atlanta Research and Education Foundation/VA Medical Center, Decatur, Georgia, United States of America
| | - Mateusz M. Plucinski
- Centers for Disease Control and Prevention, Center for Global Health, Division of Parasitic Diseases and Malaria, 1600 Clifton Rd, Mail Stop D-67, Atlanta, Georgia, United States of America
- President’s Malaria Initiative, Atlanta, Georgia, United States of America
| | - John W. Barnwell
- Centers for Disease Control and Prevention, Center for Global Health, Division of Parasitic Diseases and Malaria, 1600 Clifton Rd, Mail Stop D-67, Atlanta, Georgia, United States of America
| | - Venkatachalam Udhayakumar
- Centers for Disease Control and Prevention, Center for Global Health, Division of Parasitic Diseases and Malaria, 1600 Clifton Rd, Mail Stop D-67, Atlanta, Georgia, United States of America
| |
Collapse
|
38
|
Tadesse FG, Pett H, Baidjoe A, Lanke K, Grignard L, Sutherland C, Hall T, Drakeley C, Bousema T, Mamo H. Submicroscopic carriage of Plasmodium falciparum and Plasmodium vivax in a low endemic area in Ethiopia where no parasitaemia was detected by microscopy or rapid diagnostic test. Malar J 2015; 14:303. [PMID: 26242243 PMCID: PMC4524028 DOI: 10.1186/s12936-015-0821-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 07/23/2015] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Motivated by the success in malaria control that was documented over the last decade Ethiopia is aiming at malaria elimination by 2020 in selected districts. It is currently unknown if asymptomatic, submicroscopic malaria parasite carriage may form a hurdle to achieve elimination. The elimination effort may further be complicated by possible glucose-6 phosphate dehydrogenase (G6PD) deficiency which would hinder the use of 8-aminoquinolines in the elimination efforts. METHOD In February 2014 a community-based cross-sectional survey was conducted in Malo, southwest Ethiopia. Finger-prick blood samples (n = 555) were tested for presence of Plasmodium falciparum and Plasmodium vivax with microscopy, rapid diagnostic test (RDT), and nested polymerase chain reaction (nPCR). Multiplicity of P. falciparum infections was determined based on genotyping the polymorphic merozoite surface protein-2 (MSP-2) gene. Individuals were also genotyped for mutations in the gene that produces G6PD. RESULTS All study participants were malaria infection negative by microscopy and RDT. Nested PCR revealed P. falciparum mono-infection in 5.2% (29/555), P. vivax mono-infection in 4.3% (24/555) and mixed infection in 0.2% (1/555) of individuals. All parasitemic individuals were afebrile (axillary temperature <37.5°C). None of the study participants carried mutations for the G6PD African A-(202GA) and Mediterranean (563CT) variants. All infections, except one, were single-clone infection by MSP-2 genotyping. CONCLUSION The detection of a substantial number of subpatent malaria infections in an apparently asymptomatic population without evidence for malaria transmission by conventional diagnostics raises questions about the path to malaria elimination. It is currently unknown how important these infections are for sustaining malaria transmission in the study sites. The absence of G6PD deficiency indicates that 8-aminoquinolines may be safely deployed to accelerate elimination initiatives.
Collapse
Affiliation(s)
- Fitsum G Tadesse
- Department of Medical Microbiology, Radboud University Medical Centre, Geert Grooteplein 26-28, 6525GA, Nijmegen, The Netherlands.
- Medical Biotechnology Unit, Institute of Biotechnology, Addis Ababa University, POBox 1176, Addis Ababa, Ethiopia.
| | - Helmi Pett
- Department of Medical Microbiology, Radboud University Medical Centre, Geert Grooteplein 26-28, 6525GA, Nijmegen, The Netherlands.
| | - Amrish Baidjoe
- Department of Medical Microbiology, Radboud University Medical Centre, Geert Grooteplein 26-28, 6525GA, Nijmegen, The Netherlands.
| | - Kjerstin Lanke
- Department of Medical Microbiology, Radboud University Medical Centre, Geert Grooteplein 26-28, 6525GA, Nijmegen, The Netherlands.
| | - Lynn Grignard
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Colin Sutherland
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Tom Hall
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Chris Drakeley
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Teun Bousema
- Department of Medical Microbiology, Radboud University Medical Centre, Geert Grooteplein 26-28, 6525GA, Nijmegen, The Netherlands.
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Hassen Mamo
- Department of Microbial, Cellular and Molecular Biology, College of Natural Sciences, Addis Ababa University, POBox 1176, Addis Ababa, Ethiopia.
| |
Collapse
|
39
|
Serologically defined variations in malaria endemicity in Pará state, Brazil. PLoS One 2014; 9:e113357. [PMID: 25419900 PMCID: PMC4242530 DOI: 10.1371/journal.pone.0113357] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 10/25/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Measurement of malaria endemicity is typically based on vector or parasite measures. A complementary approach is the detection of parasite specific IgG antibodies. We determined the antibody levels and seroconversion rates to both P. vivax and P. falciparum merozoite antigens in individuals living in areas of varying P. vivax endemicity in Pará state, Brazilian Amazon region. METHODOLOGY/PRINCIPAL FINDINGS The prevalence of antibodies to recombinant antigens from P. vivax and P. falciparum was determined in 1,330 individuals. Cross sectional surveys were conducted in the north of Brazil in Anajás, Belém, Goianésia do Pará, Jacareacanga, Itaituba, Trairão, all in the Pará state, and Sucuriju, a free-malaria site in the neighboring state Amapá. Seroprevalence to any P. vivax antigens (MSP1 or AMA-1) was 52.5%, whereas 24.7% of the individuals were seropositive to any P. falciparum antigens (MSP1 or AMA-1). For P. vivax antigens, the seroconversion rates (SCR) ranged from 0.005 (Sucuriju) to 0.201 (Goianésia do Pará), and are strongly correlated to the corresponding Annual Parasite Index (API). We detected two sites with distinct characteristics: Goianésia do Pará where seroprevalence curve does not change with age, and Sucuriju where seroprevalence curve is better described by a model with two SCRs compatible with a decrease in force of infection occurred 14 years ago (from 0.069 to 0.005). For P. falciparum antigens, current SCR estimates varied from 0.002 (Belém) to 0.018 (Goianésia do Pará). We also detected a putative decrease in disease transmission occurred ∼29 years ago in Anajás, Goianésia do Pará, Itaituba, Jacareacanga, and Trairão. CONCLUSIONS We observed heterogeneity of serological indices across study sites with different endemicity levels and temporal changes in the force of infection in some of the sites. Our study provides further evidence that serology can be used to measure and monitor transmission of both major species of malaria parasite.
Collapse
|
40
|
White MT, Karl S, Battle KE, Hay SI, Mueller I, Ghani AC. Modelling the contribution of the hypnozoite reservoir to Plasmodium vivax transmission. eLife 2014; 3. [PMID: 25406065 PMCID: PMC4270097 DOI: 10.7554/elife.04692] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 11/13/2014] [Indexed: 12/25/2022] Open
Abstract
Plasmodium vivax relapse infections occur following activation of latent liver-stages parasites (hypnozoites) causing new blood-stage infections weeks to months after the initial infection. We develop a within-host mathematical model of liver-stage hypnozoites, and validate it against data from tropical strains of P. vivax. The within-host model is embedded in a P. vivax transmission model to demonstrate the build-up of the hypnozoite reservoir following new infections and its depletion through hypnozoite activation and death. The hypnozoite reservoir is predicted to be over-dispersed with many individuals having few or no hypnozoites, and some having intensely infected livers. Individuals with more hypnozoites are predicted to experience more relapses and contribute more to onwards P. vivax transmission. Incorporating hypnozoite killing drugs such as primaquine into first-line treatment regimens is predicted to cause substantial reductions in P. vivax transmission as individuals with the most hypnozoites are more likely to relapse and be targeted for treatment. DOI:http://dx.doi.org/10.7554/eLife.04692.001 Malaria is one of the world's most deadly infections, causing 100s of 1000s of deaths each year despite being both preventable and curable. Malaria is caused by Plasmodium parasites, which are transmitted between humans by mosquitoes. When a mosquito bites a human, Plasmodium is injected into the bloodstream with the mosquito's saliva. The parasite then travels through the bloodstream to the liver, infects liver cells and multiplies within those cells without causing any noticeable symptoms. After remaining silent in the liver for weeks or months, the now abundant parasite ruptures the host liver cell, re-enters the bloodstream, and begins infecting red blood cells. If another mosquito bites the infected individual and takes a blood meal, the parasite moves into the mosquito and the cycle of transmission continues. There are several species of Plasmodium that are known to cause malaria. The most widely studied species is P. falciparum, which also causes one of the deadliest types of malaria. However, another Plasmodium species called P. vivax is the most widely distributed species and, despite being less virulent than P. falciparum, is particularly dangerous because it causes recurring malaria. In contrast to P. falciparum, P. vivax has the ability to form hypnozoites: a dormant form of the parasite that can remain inside liver cells for long periods of time, sometimes for years. The reservoir of P. vivax hypnozoites can regularly populate the bloodstream with the infectious form of the parasite, triggering relapses of malaria. Even if an individual suffering a relapse receives prompt treatment to clear parasites in the blood, more parasites may emerge from the liver and cause new blood-stage infections. White et al. developed a mathematical model to help understand how P. vivax is transmitted. Unlike many of the established models of malaria transmission, the new model accounts for the reservoir of P. vivax hypnozoites in the liver, and assumes that hypnozoites in the reservoir either die, or are activated and enter the bloodstream, at a constant rate. This produces patterns that closely match how often relapses occur in patients. White et al. go on to predict that although many infected people have few or no hypnozoites in their liver, some have many hypnozoites, and these people are more likely to suffer from malaria relapses. This suggests that if the initial treatments given to malaria sufferers incorporate additional drugs that kill the hypnozoites in the liver, then it may be possible to substantially reduce the extent of P. vivax transmission. DOI:http://dx.doi.org/10.7554/eLife.04692.002
Collapse
Affiliation(s)
- Michael T White
- MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Stephan Karl
- Department of Infection and Immunity, Walter and Eliza Hall Institute, Melbourne, Australia
| | - Katherine E Battle
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Simon I Hay
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Ivo Mueller
- Department of Infection and Immunity, Walter and Eliza Hall Institute, Melbourne, Australia
| | - Azra C Ghani
- MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| |
Collapse
|
41
|
Sheikh IH, Kaushal DC, Singh V, Kumar N, Chandra D, Kaushal NA. Cloning, overexpression and characterization of soluble 42kDa fragment of merozoite surface protein-1 of Plasmodium vivax. Protein Expr Purif 2014; 103:64-74. [PMID: 25195175 DOI: 10.1016/j.pep.2014.08.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 08/19/2014] [Accepted: 08/25/2014] [Indexed: 11/24/2022]
Abstract
Plasmodium vivax represents the second most prevalent malaria species of major public health importance and the global eradication of malaria requires the development of vaccines to prevent infection. The lack of in vitro culture and a suitable animal model for P. vivax malaria are the major problems for the delay in developing a functional vivax vaccine. A number of antigens have been identified for P. vivax as potential malaria vaccine candidates and among these 42kDa fragment of merozoite surface protein-1 (MSP-142) is one of most promising antigen of asexual blood stage. In most of the earlier studies, the MSP-142 of malaria parasites was expressed as insoluble protein in inclusion bodies and it is difficult to get purified protein in conformation form. In the present study, we have cloned, overexpressed and characterized the 42kDa fragment of P. vivax MSP-1 as soluble protein in Escherichiacoli. The 42kDa gene fragment of P. vivax MSP-1 was PCR amplified using specific primers, sequenced and subcloned into pTriEx-4 expression vector. The optimum expression of recombinant P. vivax protein was obtained in SOC growth medium by inducing with 0.2mM IPTG at 37°C for 4h. The SDS-PAGE analysis showed a fusion protein of 55kDa and about 80% was present in soluble form. The purified P. vivax MSP-142 was characterized and found to be correctly folded and in conformation form as evident by CD spectroscopy, presence of 1 free -SH group and the reactivity with reduction sensitive conformational monoclonals against P. vivax MSP-142.
Collapse
Affiliation(s)
- Inayat Hussain Sheikh
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226031, India; Department of Biochemistry, Lucknow University, Lucknow, India
| | - Deep C Kaushal
- Amity University Uttar Pradesh, Lucknow Campus, Lucknow 226010, India
| | - Vandana Singh
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Niraj Kumar
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Deepak Chandra
- Department of Biochemistry, Lucknow University, Lucknow, India
| | - Nuzhat A Kaushal
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226031, India.
| |
Collapse
|
42
|
Ariey F, Paul RE. Antimalarial resistance: is vivax left behind? THE LANCET. INFECTIOUS DISEASES 2014; 14:908-9. [PMID: 25213734 DOI: 10.1016/s1473-3099(14)70921-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Frédéric Ariey
- Genetics and Genomics of Insect Vectors Unit, Institut Pasteur, Paris 75724, France.
| | - Richard E Paul
- Functional Genetics of Infectious Diseases Unit, Institut Pasteur, Paris 75724, France
| |
Collapse
|
43
|
Epidemiology of disappearing Plasmodium vivax malaria: a case study in rural Amazonia. PLoS Negl Trop Dis 2014; 8:e3109. [PMID: 25166263 PMCID: PMC4148206 DOI: 10.1371/journal.pntd.0003109] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 07/11/2014] [Indexed: 11/19/2022] Open
Abstract
Background New frontier settlements across the Amazon Basin pose a major challenge for malaria elimination in Brazil. Here we describe the epidemiology of malaria during the early phases of occupation of farming settlements in Remansinho area, Brazilian Amazonia. We examine the relative contribution of low-density and asymptomatic parasitemias to the overall Plasmodium vivax burden over a period of declining transmission and discuss potential hurdles for malaria elimination in Remansinho and similar settings. Methods Eight community-wide cross-sectional surveys, involving 584 subjects, were carried out in Remansinho over 3 years and complemented by active and passive surveillance of febrile illnesses between the surveys. We used quantitative PCR to detect low-density asexual parasitemias and gametocytemias missed by conventional microscopy. Mixed-effects multiple logistic regression models were used to characterize independent risk factors for P. vivax infection and disease. Principal Findings/Conclusions P. vivax prevalence decreased from 23.8% (March–April 2010) to 3.0% (April–May 2013), with no P. falciparum infections diagnosed after March–April 2011. Although migrants from malaria-free areas were at increased risk of malaria, their odds of having P. vivax infection and disease decreased by 2–3% with each year of residence in Amazonia. Several findings indicate that low-density and asymptomatic P. vivax parasitemias may complicate residual malaria elimination in Remansinho: (a) the proportion of subpatent infections (i.e. missed by microscopy) increased from 43.8% to 73.1% as P. vivax transmission declined; (b) most (56.6%) P. vivax infections were asymptomatic and 32.8% of them were both subpatent and asymptomatic; (c) asymptomatic parasite carriers accounted for 54.4% of the total P. vivax biomass in the host population; (d) over 90% subpatent and asymptomatic P. vivax had PCR-detectable gametocytemias; and (e) few (17.0%) asymptomatic and subpatent P. vivax infections that were left untreated progressed to clinical disease over 6 weeks of follow-up and became detectable by routine malaria surveillance. Despite decades of control efforts, malaria remains a major public health concern in Brazil. A large proportion of the 243,000 cases diagnosed per year originate from areas of recent colonization in the densely forested Amazon Basin. This population-based longitudinal study addresses the epidemiology of malaria during the early stages of colonization of frontier settlements in Remansinho area, rural Amazonia. We documented a major decline in the prevalence of P. vivax infection, from 23.8% to 3.0%, between March–April 2010 and April–May 2013. Up to 73.1% of the P. vivax infections were missed by microscopy as malaria transmission declined and most (56.6%) of these infections caused no clinical signs or symptoms. Few (17.0%) asymptomatic P. vivax infections that were left untreated eventually progressed to clinical disease, becoming detectable by routine malaria surveillance, over 6 weeks of follow-up. Moreover, nearly all P. vivax infections that were undetected by microscopy had gametocytes, the parasite's blood stages responsible for malaria transmission to mosquito vectors, detected by molecular methods. These findings indicate that apparently healthy carriers of low-density parasitemias, who are often missed by conventional microscopy, contribute significantly to ongoing P. vivax transmission and may further complicate residual malaria elimination in Remansinho and similar endemic settings.
Collapse
|
44
|
Chootong P, McHenry AM, Ntumngia FB, Sattabongkot J, Adams JH. The association of Duffy binding protein region II polymorphisms and its antigenicity in Plasmodium vivax isolates from Thailand. Parasitol Int 2014; 63:858-64. [PMID: 25108177 DOI: 10.1016/j.parint.2014.07.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 07/15/2014] [Accepted: 07/28/2014] [Indexed: 11/19/2022]
Abstract
Plasmodium vivax Duffy binding protein II (DBPII) plays an important role in reticulocyte invasion and is a potential vaccine candidate against vivax malaria. However, polymorphisms in DBPII are a challenge for the successful design of a broadly protective vaccine. In this study, the genetic diversity of DBPII among Thai isolates was analyzed from Plasmodium vivax-infected blood samples and polymorphism characters were defined with the MEGA4 program. Sequence analysis identified 12 variant residues that are common among Thai DBPII haplotypes with variant residues L333F, L424I, W437R and I503K having the highest frequency. Variant residue D384K occurs in combination with either E385K or K386N/Q. Additionally, variant residue L424I occurs in conjunction with W437R in most Thai DBPII alleles and these variants frequently occur in combination with the I503K variant. The polymorphic patterns of Thai isolates were defined into 9 haplotypes (Thai DBL-1, -2, -3, etc.…). Thai DBL-2, -5, -6 haplotypes are the most common DBPII variants in Thai residents. To study the association of these Thai DBPII polymorphisms with antigenic character, the functional inhibition of anti-DBPII monoclonal antibodies against a panel of Thai DBL variants was characterized by an in vitro erythrocyte binding inhibition assay. The functional inhibition of anti-DBPII monoclonal antibodies 3C9, 2D10 and 2C6 against Thai variants was significantly different, suggesting that polymorphisms of Thai DBPII variants alter the antigenic character of the target epitopes. In contrast, anti-DBPII monoclonal antibody 2H2 inhibited all Thai DBPII variants equally well. Our results suggest that the immune efficacy of a DBPII vaccine will depend on the specificity of the anti-DBPII antibodies induced and that it is preferable to optimize responses to conserved epitopes for broadly neutralizing protection against P. vivax.
Collapse
MESH Headings
- Alleles
- Animals
- Antibodies, Monoclonal
- Antibodies, Neutralizing/immunology
- Antibodies, Protozoan/immunology
- Antigens, Protozoan/genetics
- Antigens, Protozoan/immunology
- COS Cells
- Chlorocebus aethiops
- Erythrocytes/parasitology
- Haplotypes
- Malaria, Vivax/immunology
- Malaria, Vivax/parasitology
- Mice
- Phylogeny
- Plasmodium vivax/genetics
- Plasmodium vivax/immunology
- Polymorphism, Genetic
- Protozoan Proteins/genetics
- Protozoan Proteins/immunology
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/immunology
- Sequence Analysis, DNA
- Thailand
Collapse
Affiliation(s)
- Patchanee Chootong
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand.
| | - Amy M McHenry
- Department of Biology, Southwestern Adventist University, Keene, TX, United States
| | - Francis B Ntumngia
- Department of Global Health, University of South Florida, Tampa, FL, United States
| | | | - John H Adams
- Department of Global Health, University of South Florida, Tampa, FL, United States
| |
Collapse
|
45
|
Chang KS, Shin EH, Yoo DH, Ahn YJ. Enhanced toxicity of binary mixtures of Bacillus thuringiensis subsp. israelensis and three essential oil major constituents to wild Anopheles sinensis (Diptera: Culicidae) and Aedes albopictus (Diptera: Culicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2014; 51:804-810. [PMID: 25118412 DOI: 10.1603/me13128] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
An assessment was made of the toxicity of 12 insecticides and three essential oils as well as Bacillus thuringiensis subsp. israelensis (Bti) alone or in combination with the oil major constituents (E)-anethole (AN), (E) -cinnamaldehyde (CA), and eugenol (EU; 1:1 ratio) to third instars of bamboo forest-collected Aedes albopictus (Skuse) and rice paddy field-collected Anopheles sinensis Wiedemann. An. sinensis larvae were resistant to various groups of the tested insecticides. Based on 24-h LC50 values, binary mixtures of Bti and CA, AN, or EU were significantly more toxic against Ae. albopictus larvae (0.0084, 0.0134, and 0.0237 mg/liter) and An. sinensis larvae (0.0159, 0.0388, and 0.0541 mg/liter) than either Bti (1.7884 and 2.1681 mg/liter) or CA (11.46 and 18.56 mg/liter), AN (16.66 and 25.11 mg/liter), or EU (24.60 and 31.09 mg/liter) alone. As judged by cotoxicity coefficient (CC) and synergistic factor (SF), the three binary mixtures operated in a synergy pattern (CC, 140.7-368.3 and SF, 0.0007-0.0010 for Ae. albopictus; CC, 75.1-245.3 and SF, 0.0008-0.0017 for An. sinensis). Global efforts to reduce the level of highly toxic synthetic insecticides in the aquatic environment justify further studies on the binary mixtures of Bti and essential oil constituents described, in particular CA, as potential larvicides for the control of malaria vector mosquito populations.
Collapse
|
46
|
Prevalence of mutations in the antifolates resistance-associated genes (dhfr and dhps) in Plasmodium vivax parasites from Eastern and Central Sudan. INFECTION GENETICS AND EVOLUTION 2014; 26:153-9. [PMID: 24861816 DOI: 10.1016/j.meegid.2014.05.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 05/10/2014] [Accepted: 05/14/2014] [Indexed: 01/17/2023]
Abstract
Plasmodium vivax is the most geographically widespread species, and its burden has been increasingly documented in Eastern and Central Sudan. P. vivax becomes the crucial challenge during elimination programs; thus an effective treatment is necessary to prevent the development and the spread of resistant parasites. Therefore, the main objective of the present study was to provide data on the prevalence of molecular markers in two genes (pvdhfr and pvdhps) associated with SP resistance after nine years of AS+SP deployment among P. vivax parasites from Eastern and Central Sudan using PCR-RFLP. During 2012-2013, a number of 66 blood spots were obtained on filter paper. The samples were collected before treatment from febrile patients who were microscopically positive for P. vivax, from three states in Eastern and Central Sudan (Gezira, Gedarif, and Kassala). Mutations were detected in three codons of pvdhfr (I13L, S58R, and S117N) and none in pvdhps. The majority of P. vivax parasites had double mutations (58R/117N, 58%) in dhfr gene, while all parasites were wild type in dhps gene. In addition, limited distinct haplotypes (n=4) were detected. In conclusion, the prevalence of mutations associated with SP resistance is low in Eastern and Central Sudan. Such information is necessary for guiding malaria control measures in the frame of Roll Back Malaria strategies for the elimination of malaria in the world.
Collapse
|
47
|
Battle KE, Karhunen MS, Bhatt S, Gething PW, Howes RE, Golding N, Van Boeckel TP, Messina JP, Shanks GD, Smith DL, Baird JK, Hay SI. Geographical variation in Plasmodium vivax relapse. Malar J 2014; 13:144. [PMID: 24731298 PMCID: PMC4021508 DOI: 10.1186/1475-2875-13-144] [Citation(s) in RCA: 194] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 03/31/2014] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Plasmodium vivax has the widest geographic distribution of the human malaria parasites and nearly 2.5 billion people live at risk of infection. The control of P. vivax in individuals and populations is complicated by its ability to relapse weeks to months after initial infection. Strains of P. vivax from different geographical areas are thought to exhibit varied relapse timings. In tropical regions strains relapse quickly (three to six weeks), whereas those in temperate regions do so more slowly (six to twelve months), but no comprehensive assessment of evidence has been conducted. Here observed patterns of relapse periodicity are used to generate predictions of relapse incidence within geographic regions representative of varying parasite transmission. METHODS A global review of reports of P. vivax relapse in patients not treated with a radical cure was conducted. Records of time to first P. vivax relapse were positioned by geographic origin relative to expert opinion regions of relapse behaviour and epidemiological zones. Mixed-effects meta-analysis was conducted to determine which geographic classification best described the data, such that a description of the pattern of relapse periodicity within each region could be described. Model outputs of incidence and mean time to relapse were mapped to illustrate the global variation in relapse. RESULTS Differences in relapse periodicity were best described by a historical geographic classification system used to describe malaria transmission zones based on areas sharing zoological and ecological features. Maps of incidence and time to relapse showed high relapse frequency to be predominant in tropical regions and prolonged relapse in temperate areas. CONCLUSIONS The results indicate that relapse periodicity varies systematically by geographic region and are categorized by nine global regions characterized by similar malaria transmission dynamics. This indicates that relapse may be an adaptation evolved to exploit seasonal changes in vector survival and therefore optimize transmission. Geographic patterns in P. vivax relapse are important to clinicians treating individual infections, epidemiologists trying to infer P. vivax burden, and public health officials trying to control and eliminate the disease in human populations.
Collapse
Affiliation(s)
- Katherine E Battle
- Department of Zoology, Spatial Ecology and Epidemiology Group, Tinbergen Building, University of Oxford, South Parks Road, Oxford, UK
| | - Markku S Karhunen
- Department of Zoology, Spatial Ecology and Epidemiology Group, Tinbergen Building, University of Oxford, South Parks Road, Oxford, UK
| | - Samir Bhatt
- Department of Zoology, Spatial Ecology and Epidemiology Group, Tinbergen Building, University of Oxford, South Parks Road, Oxford, UK
| | - Peter W Gething
- Department of Zoology, Spatial Ecology and Epidemiology Group, Tinbergen Building, University of Oxford, South Parks Road, Oxford, UK
| | - Rosalind E Howes
- Department of Zoology, Spatial Ecology and Epidemiology Group, Tinbergen Building, University of Oxford, South Parks Road, Oxford, UK
| | - Nick Golding
- Department of Zoology, Spatial Ecology and Epidemiology Group, Tinbergen Building, University of Oxford, South Parks Road, Oxford, UK
| | - Thomas P Van Boeckel
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA
| | - Jane P Messina
- Department of Zoology, Spatial Ecology and Epidemiology Group, Tinbergen Building, University of Oxford, South Parks Road, Oxford, UK
| | - G Dennis Shanks
- Australian Army Malaria Institute, Enoggera, Queensland, Australia
| | - David L Smith
- Department of Epidemiology and Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
- Fogarty International Center, National Institutes of Health, Bethesda, MD, USA
| | - J Kevin Baird
- Eijkman-Oxford Clinical Research Unit, Jalan Diponegoro No 69, Jakarta, Indonesia
- Nuffield Department of Medicine, Centre for Tropical Medicine, University of Oxford, Oxford, UK
| | - Simon I Hay
- Department of Zoology, Spatial Ecology and Epidemiology Group, Tinbergen Building, University of Oxford, South Parks Road, Oxford, UK
- Fogarty International Center, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
48
|
Hsiang MS, Hwang J, Tao AR, Liu Y, Bennett A, Shanks GD, Cao J, Kachur SP, Feachem RGA, Gosling RD, Gao Q. Mass drug administration for the control and elimination of Plasmodium vivax malaria: an ecological study from Jiangsu province, China. Malar J 2013; 12:383. [PMID: 24175930 PMCID: PMC3842644 DOI: 10.1186/1475-2875-12-383] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 10/24/2013] [Indexed: 12/05/2022] Open
Abstract
Background Recent progress in malaria control has caused renewed interest in mass drug administration (MDA) as a potential elimination strategy but the evidence base is limited. China has extensive experience with MDA, but it is not well documented. Methods An ecological study was conducted to describe the use of MDA for the control and elimination of Plasmodium vivax in Jiangsu Province and explore the association between MDA and malaria incidence. Two periods were focused on: 1973 to 1983 when malaria burden was high and MDA administered to highly endemic counties province-wide, and 2000 to 2009, when malaria burden was low and a focal approach was used in two counties. All available data about the strategies implemented, MDA coverage, co-interventions, incidence, and adverse events were collected and described. Joinpoint analysis was used to describe trends in incidence and the relationship between MDA coverage and incidence was explored in negative binomial regression models. Results From 1973 to 1983, MDA with pyrimethamine and primaquine was used on a large scale, with up to 30 million people in target counties covered in a peak year (50% of the total population). Joinpoint analyses identified declines in annual incidence, -56.7% (95% CI -75.5 to -23.7%) from 1973–1976 and -12.4% (95% CI -24.7 to 2.0%) from 1976–1983. Population average negative binomial models identified a relationship between higher total population MDA coverage and lower monthly incidence from 1973–1976, IRR 0.98 (95% CI 0.97 to 1.00), while co-interventions, rainfall and GDP were not associated. From 2000–2009, incidence in two counties declined (annual change -43.7 to -14.0%) during a time when focal MDA using chloroquine and primaquine was targeted to villages and/or individuals residing near passively detected index cases (median 0.04% of total population). Although safety data were not collected systematically, there were rare reports of serious but non-fatal events. Conclusions In Jiangsu Province, China, large-scale MDA was implemented and associated with declines in high P. vivax malaria transmission; a more recent focal approach may have contributed to interruption of transmission. MDA should be considered a potential key strategy for malaria control and elimination.
Collapse
Affiliation(s)
- Michelle S Hsiang
- Global Health Group, University of California San Francisco (UCSF), San Francisco, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Chareonviriyaphap T, Bangs MJ, Suwonkerd W, Kongmee M, Corbel V, Ngoen-Klan R. Review of insecticide resistance and behavioral avoidance of vectors of human diseases in Thailand. Parasit Vectors 2013; 6:280. [PMID: 24294938 PMCID: PMC3850650 DOI: 10.1186/1756-3305-6-280] [Citation(s) in RCA: 147] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 09/20/2013] [Indexed: 11/10/2022] Open
Abstract
Physiological resistance and behavioral responses of mosquito vectors to insecticides are critical aspects of the chemical-based disease control equation. The complex interaction between lethal, sub-lethal and excitation/repellent ('excito-repellent') properties of chemicals is typically overlooked in vector management and control programs. The development of "physiological" resistance, metabolic and/or target site modifications, to insecticides has been well documented in many insect groups and disease vectors around the world. In Thailand, resistance in many mosquito populations has developed to all three classes of insecticidal active ingredients currently used for vector control with a majority being synthetic-derived pyrethroids. Evidence of low-grade insecticide resistance requires immediate countermeasures to mitigate further intensification and spread of the genetic mechanisms responsible for resistance. This can take the form of rotation of a different class of chemical, addition of a synergist, mixtures of chemicals or concurrent mosaic application of different classes of chemicals. From the gathered evidence, the distribution and degree of physiological resistance has been restricted in specific areas of Thailand in spite of long-term use of chemicals to control insect pests and disease vectors throughout the country. Most surprisingly, there have been no reported cases of pyrethroid resistance in anopheline populations in the country from 2000 to 2011. The precise reasons for this are unclear but we assume that behavioral avoidance to insecticides may play a significant role in reducing the selection pressure and thus occurrence and spread of insecticide resistance. The review herein provides information regarding the status of physiological resistance and behavioral avoidance of the primary mosquito vectors of human diseases to insecticides in Thailand from 2000 to 2011.
Collapse
Affiliation(s)
| | - Michael J Bangs
- Public Health & Malaria Control Department, International SOS, Kuala Kencana, Papua 99920, Indonesia
| | - Wannapa Suwonkerd
- Department of Disease Control, Ministry of Public Health, Chiang Mai 52000, Thailand
| | - Monthathip Kongmee
- Department of Entomology, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand
| | - Vincent Corbel
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok 10900, Thailand
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC, IRD 224-CNRS 5290 UM1-UM2), Montpellier, France
| | - Ratchadawan Ngoen-Klan
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok 10900, Thailand
| |
Collapse
|
50
|
Rahul C, Shiva Krishna K, Meera Bai N, Kumar V, Phadke S, Rajesh V. Plasmodium vivax: C-terminal diversity in the blood stage SERA genes from Indian field isolates. Exp Parasitol 2013; 134:82-91. [DOI: 10.1016/j.exppara.2013.02.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 12/21/2012] [Accepted: 02/05/2013] [Indexed: 10/27/2022]
|