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Kirar M, Singh SP, Singh H, Sehrawat N. Efficacy of maturase K and rpL20 protein extracted from C. procera leaves on Anophelesstephensi. Toxicon 2024; 243:107714. [PMID: 38626820 DOI: 10.1016/j.toxicon.2024.107714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 04/05/2024] [Accepted: 04/09/2024] [Indexed: 04/26/2024]
Abstract
The present work is carried out to protein isolation, purification, and characterization from leaves, stem, and seed of C. procera and to evaluate the larvicidal potential on Anopheles stephensi. The whole protein was isolated using protein extraction buffer and precipitated by ammonium sulphate and larvicidal active protein was purified by the column chromatography. The homogeneity of larvicidal protein was confirmed by the SDS-PAGE. The identification of protein was done by the HPLC and LC-MS/ESI-MS. The crude protein from leaves showed 100% mortality of 3rd instar larvae of An. stephensi at the concentration of 5.5 mg/ml after 24 h of exposure. The crude protein from stem showed 25% mortality and no mortality observed was observed in seed protein. The leaves crude protein was further purified by ion exchange chromatography and eluted fractions were tested for larvicidal potential. The purified single protein fractions L2 and L3 from C. procera leaves showed 100% mortality at concentration of 0.06 mg/ml. The homogeneity of purified protein was confirmed by SDS-PAGE and two bands of 26 kDa and 15 kDa protein were observed. The peptide sequence "R.SQMLENSFLIENVMKR.L" was identified in the trypsin digested homogenous protein fraction L2 and "R.DRGSQKR.N" peptide sequence in L3 fraction by LC-MS/ESI-MS. The CprL2 peptide showed the sequence similarity with the protein maturase K and CprL3 peptide showed the sequence similarity with ribosomal protein L20 of C. procera. The conserved functional domain was also identified in both the CprL2 and CprL3 peptide. The identified proteins showed strong larvicidal efficacy at very low concentration. The identified proteins are novel and natural larvicidal agents against An. stephensi and hence can be used to control the malaria.
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Affiliation(s)
- Manisha Kirar
- Department of Genetics, Maharshi Dayanand University, Rohtak, Haryana, India
| | - S P Singh
- National Institute for Malaria Research, New Delhi, India
| | - Hitesh Singh
- Department of Genetics, Maharshi Dayanand University, Rohtak, Haryana, India
| | - Neelam Sehrawat
- Department of Genetics, Maharshi Dayanand University, Rohtak, Haryana, India.
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Kokori E, Olatunji G, Akinboade A, Akinoso A, Egbunu E, Aremu SA, Okafor CE, Oluwole O, Aderinto N. Triple artemisinin-based combination therapy (TACT): advancing malaria control and eradication efforts. Malar J 2024; 23:25. [PMID: 38238781 PMCID: PMC10797909 DOI: 10.1186/s12936-024-04844-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Accepted: 01/05/2024] [Indexed: 01/22/2024] Open
Abstract
This paper examines the far-reaching implications of Triple Artemisinin-Based Combination Therapy (TACT) in the global battle against malaria. Artemisinin-Based Combination Therapy (ACT) is recognized for its cost-effectiveness, lower likelihood of adverse events, and widespread acceptance by patients and healthcare providers. However, TACT introduces novel dimensions to the fight against malaria that make them a superior choice in several aspects. TACT has been demonstrated to address resistance, offer a broader spectrum of action, reduce the risk of treatment failure, and can be tailored to meet regional needs, strengthening the global effort to combat malaria. However, maximizing these benefits of TACT depends on accessibility, particularly in resource-limited regions where malaria is most prevalent. Collaborative efforts among stakeholders, sustainable pricing strategies, efficient supply chains, and public-private partnerships are essential to ensure that TACT reaches needy populations. Moreover, dispelling prevalent malaria myths through health education campaigns is critical in this endeavour. The paper underscores the significance of collaborative initiatives and partnerships among governments, international organizations, research institutions, acadaemia, pharmaceutical companies, and local communities. Together, these efforts can pave the way for the acceptance, adoption, and success of TACT, ultimately advancing the global goal of a malaria-free world.
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Affiliation(s)
- Emmanuel Kokori
- Department of Medicine and Surgery, University of Ilorin, Ilorin, Kwara, Nigeria
| | - Gbolahan Olatunji
- Department of Medicine and Surgery, University of Ilorin, Ilorin, Kwara, Nigeria
| | - Adeola Akinboade
- Department of Medicine and Surgery, University of Ilorin, Ilorin, Kwara, Nigeria
| | - Aminat Akinoso
- Department of Medicine and Surgery, University of Ilorin, Ilorin, Kwara, Nigeria
| | | | | | | | | | - Nicholas Aderinto
- Department of Medicine, Ladoke Akintola University of Technology, Ogbomosho, Nigeria.
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Tajudeen YA, Oladipo HJ, Oladunjoye IO, Oladipo MK, Shittu HD, Abdulmumeen IF, Afolabi AO, El-Sherbini MS. Transforming malaria prevention and control: the prospects and challenges of gene drive technology for mosquito management. Ann Med 2024; 55:2302504. [PMID: 38232762 PMCID: PMC10795774 DOI: 10.1080/07853890.2024.2302504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 01/02/2024] [Indexed: 01/19/2024] Open
Abstract
Background: In the era of insecticides and anti-malarial drug resistance, gene drive technology holds considerable promise for malaria control. Gene drive technology deploys genetic modifications into mosquito populations to impede their ability to transmit the malaria parasite. This can be either through the disruption of an essential mosquito gene or the association of gene drive with a desirable effector gene. CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is a gene editing tool that precisely modifies mosquito vector DNA sequences and curtails the rate of pathogen transmission.Methods: A comprehensive search was conducted in the SCOPUS and MEDLINE databases (via PubMed) until October 2023. The keywords used were related to the principles and mechanisms of gene drive technology, its advantages, and disadvantages, and its ethical and regulatory considerations in sustainable malaria eradication.Results: The development of gene drive enables the preferential inheritance of specific genes in targeted mosquitoes, potentially obstructing the transmission of the Plasmodium parasite. This technology was also studied for the control of other vector-borne diseases such as dengue and chikungunya viruses. Despite its experimental superiority over other traditional methods such as insecticide-treated nets and insecticide sprays, the long-term dynamic interplay of mutation and resistance poses challenges for gene drive efficiency in sustainable malaria control.Conclusions: This commentary elucidates the underlying mechanisms and principles of gene drive technology, underscoring its promise and challenges as a novel strategy to curtail malaria prevalence. Although the release of such genetically modified mosquitoes into the natural environment would result in the eradication of the locally targeted species of mosquitoes, the complete eradication of the entire species remains questionable. Thus, the practical application raises significant ethical and regulatory concerns for further research and risk assessment, including the risk of gene drive spreading to nontarget species in the wider theatre of biodiverse species.
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Affiliation(s)
- Yusuf Amuda Tajudeen
- Department of Epidemiology and Medical Statistics, Faculty of Public Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
- Department of Microbiology, Faculty of Life Sciences, University of Ilorin, Ilorin, Nigeria
| | - Habeebullah Jayeola Oladipo
- Department of Microbiology, Faculty of Life Sciences, University of Ilorin, Ilorin, Nigeria
- Faculty of Pharmaceutical Sciences, University of Ilorin, Ilorin, Nigeria
| | | | | | | | - Imam-Fulani Abdulmumeen
- Faculty of health science, Department of Public health, Alhikmah University Ilorin, Ilorin, Nigeria
| | - Abdullateef Opeyemi Afolabi
- Faculty of Biomedical Sciences, Department of Microbiology and Immunology, Kampala International University, Bushenyi, Uganda
| | - Mona Said El-Sherbini
- Department of Medical Parasitology, Faculty of Medicine, Cairo University, Cairo, Egypt
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Kua KP, Lee SWH, Chongmelaxme B. The impact of home-based management of malaria on clinical outcomes in sub-Saharan African populations: a systematic review and meta-analysis. Trop Med Health 2024; 52:7. [PMID: 38191459 PMCID: PMC10773121 DOI: 10.1186/s41182-023-00572-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 12/24/2023] [Indexed: 01/10/2024] Open
Abstract
BACKGROUND Malaria remains a significant cause of morbidity and mortality globally and continues to disproportionately afflict the African population. We aimed to evaluate the effect of home management of malaria intervention on health outcomes. METHODS In our systematic review and meta-analysis, six databases (Pubmed, Cochrane CENTRAL, EMBASE, CAB Abstracts and Global Health, CINAHL Complete, and BIOSIS) were searched for studies of home management of malaria from inception until November 15, 2023. We included before-after studies, observational studies, and randomised controlled trials of home management intervention delivered in community settings. The primary outcomes were malaria mortality and all-cause mortality. The risk of bias in individual observational studies was assessed using the ROBINS-I tool, whilst randomised controlled trials were judged using a revised Cochrane risk of bias tool and cluster-randomised controlled trials were evaluated using an adapted Cochrane risk of bias tool for cluster-randomised trials. We computed risk ratios with accompanying 95% confidence intervals for health-related outcomes reported in the studies and subsequently pooled the results by using a random-effects model (DerSimonian-Laird method). RESULTS We identified 1203 citations through database and hand searches, from which 56 articles from 47 studies encompassing 234,002 participants were included in the systematic review. All studies were conducted in people living in sub-Saharan Africa and were rated to have a low or moderate risk of bias. Pooled analyses showed that mortality rates due to malaria (RR = 0.40, 95% CI = 0.29-0.54, P = 0.00001, I2 = 0%) and all-cause mortality rates (RR = 0.62, 95% CI = 0.53-0.72, P = 0.00001, I2 = 0%) were significantly lower among participants receiving home management intervention compared to the control group. However, in children under 5 years of age, there was no significant difference in mortality rates before and after implementation of home management of malaria. In terms of secondary outcomes, home management of malaria was associated with a reduction in the risk of febrile episodes (RR = 1.27, 95% CI = 1.09-1.47, P = 0.002, I2 = 97%) and higher effective rates of antimalarial treatments (RR = 2.72, 95% CI = 1.90-3.88, P < 0.00001, I2 = 96%) compared to standard care. Home malaria management combined with intermittent preventive treatment showed a significantly lower incidence risk of malaria than home management intervention that exclusively provided treatment to individuals with febrile illness suggestive of malaria. The risks for adverse events were found to be similar for home management intervention using different antimalarial drugs. Cost-effectiveness findings depicted that home malaria management merited special preferential scale-up. CONCLUSIONS Home management of malaria intervention was associated with significant reductions in malaria mortality and all-cause mortality. The intervention could help decrease health and economic burden attributable to malaria. Further clinical studies are warranted to enable more meaningful interpretations with regard to wide-scale implementation of the intervention, settings of differing transmission intensity, and new antimalarial drugs.
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Affiliation(s)
- Kok Pim Kua
- Department of Civil and Environmental Engineering, School of Engineering and Doerr School of Sustainability, Stanford University, Stanford, CA, 94305, USA
- MIT Alumni Association, Massachusetts Institute of Technology, Cambridge, MA, 02139-4822, USA
- Pharmacy Unit, Puchong Health Clinic, Petaling District Health Office, Ministry of Health Malaysia, 47100, Puchong, Selangor, Malaysia
- A.S. Watson Group, Watson's Personal Care Stores, 55188, Kuala Lumpur, Malaysia
| | - Shaun Wen Huey Lee
- School of Pharmacy, Monash University, Bandar Sunway, 47500, Subang Jaya, Selangor, Malaysia
- Asian Center for Evidence Synthesis in Population, Implementation, and Clinical Outcomes (PICO), Health and Well-Being Cluster, Global Asia in the 21st Century (GA21) Platform, Monash University, Bandar Sunway, 47500, Subang Jaya, Selangor, Malaysia
- Gerontechnology Laboratory, Global Asia in the 21st Century (GA21) Platform, Monash University, Bandar Sunway, 47500, Subang Jaya, Selangor, Malaysia
- Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya, 47500, Lakeside CampusSelangor, Malaysia
- Center for Global Health, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Bunchai Chongmelaxme
- Department of Social and Administrative Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, 10330, Thailand.
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N'Guessan R, Assi SB, Koffi A, Ahoua Alou PL, Mian A, Achee NL, Fustec B, Grieco JP, Liu F, Kumar S, Noffsinger M, Hudson A, Möhlmann TWR, Farenhorst M. EaveTubes for control of vector-borne diseases in Côte d'Ivoire: study protocol for a cluster randomized controlled trial. Trials 2023; 24:704. [PMID: 37919815 PMCID: PMC10621221 DOI: 10.1186/s13063-023-07639-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 09/11/2023] [Indexed: 11/04/2023] Open
Abstract
BACKGROUND Vector control tools, long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS), have significantly contributed to malaria prevention efforts in sub-Saharan Africa. However, insecticide resistance has seriously hampered their efficacy in recent years and new tools are essential to further progress. In2Care® EaveTubes (ETs) are an inexpensive, new resistance-breaking vector control product under World Health Organization (WHO) evaluation informed by mosquito ecology to efficiently target malaria vectors. By installing ETs in the walls of the house at the eave level that funnel the natural airflow, mosquitoes are drawn in by the same heat and odor cues that typically attract them through open eaves. Once inside an ET, mosquitoes are exposed to insecticide-treated netting placed inside the ET. The aim of this study is to test whether ETs as stand-alone tool have an effect on the epidemiology of malaria in villages where houses have been modified with the ET intervention. METHODS A two-armed, cluster randomized controlled trial will be conducted to evaluate the effect of ETs on clinical malaria incidence in children living in Côte d'Ivoire. Thirty-four villages will be selected based on population size and the proportion of houses suitable for modification with ETs (17 treatment arms (ETs + LLINs, 17 control arms (LLINs only)). Based on the population census, 55 households per cluster with eligible children (i.e., between the ages of 6 months to 8 years old at the start of the study) will be randomly selected for recruitment into the active detection cohorts. In the treatment arm, we will enroll eligible children who reside in ET-treated houses. The intervention and control cohorts will be followed for 4 months for baseline covariate measurements and 24 months with intervention. During case detection visits, blood samples will be taken from all febrile children and tested for malaria infection with rapid diagnostic tests (RDTs). All positive clinical malaria infections will be treated. To estimate the impact of the ET on malaria vector densities, entomological measurements (indoor sampling with CDC traps) will be conducted monthly in 20 clusters (10 ET, 10 Control) in 10 randomly selected households per cluster. To estimate the infectiousness of malaria vectors, sporozoite rates will be measured in subsets of the collected mosquito samples. DISCUSSION Findings will serve as an efficacy trial of ETs and will be submitted to the WHO Vector Control Advisory Group (VCAG) for assessment of public health value. Entomological outcomes will also be measured as proxies of malaria transmission to help develop guidelines for the evaluation of future In2Care® ETs products. TRIAL REGISTRATION ClinicalTrials.gov NCT05736679. Registered on 10 February 2023.
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Affiliation(s)
- Raphael N'Guessan
- Vector Control Product Evaluation Centre/Institut Pierre Richet, Bouaké, Côte d'Ivoire
| | - Serge-Brice Assi
- Vector Control Product Evaluation Centre/Institut Pierre Richet, Bouaké, Côte d'Ivoire
| | - Alphonsine Koffi
- Vector Control Product Evaluation Centre/Institut Pierre Richet, Bouaké, Côte d'Ivoire
| | | | - Anatole Mian
- Vector Control Product Evaluation Centre/Institut Pierre Richet, Bouaké, Côte d'Ivoire
| | | | | | | | - Fang Liu
- University of Notre Dame, Notre Dame, IN, USA
| | - Santosh Kumar
- Keough School of Global Affairs, University of Notre Dame, Notre Dame, IN, USA
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Tine R, Herrera S, Badji MA, Daniels K, Ndiaye P, Smith Gueye C, Tairou F, Slutsker L, Hwang J, Ansah E, Littrell M. Defining operational research priorities to improve malaria control and elimination in sub-Saharan Africa: results from a country-driven research prioritization setting process. Malar J 2023; 22:219. [PMID: 37517990 PMCID: PMC10387205 DOI: 10.1186/s12936-023-04654-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 07/22/2023] [Indexed: 08/01/2023] Open
Abstract
BACKGROUND In order to reignite gains and accelerate progress toward improved malaria control and elimination, policy, strategy, and operational decisions should be derived from high-quality evidence. The U.S. President's Malaria Initiative (PMI) Insights project together with the Université Cheikh Anta Diop of Dakar, Senegal, conducted a broad stakeholder consultation process to identify pressing evidence gaps in malaria control and elimination across sub-Saharan Africa (SSA), and developed a priority list of country-driven malaria operational research (OR) and programme evaluation (PE) topics to address these gaps. METHODS Five key stakeholder groups were engaged in the process: national malaria programmes (NMPs), research institutions in SSA, World Health Organization (WHO) representatives in SSA, international funding agencies, and global technical partners who support malaria programme implementation and research. Stakeholders were engaged through individual or small group interviews and an online survey, and asked about key operational challenges faced by NMPs, pressing evidence gaps in current strategy and implementation guidance, and priority OR and PE questions to address the challenges and gaps. RESULTS Altogether, 47 interviews were conducted with 82 individuals, and through the online survey, input was provided by 46 global technical partners. A total of 33 emergent OR and PE topics were identified through the consultation process and were subsequently evaluated and prioritized by an external evaluation committee of experts from NMPs, research institutions, and the WHO. The resulting prioritized OR and PE topics predominantly focused on generating evidence needed to close gaps in intervention coverage, address persistent challenges faced by NMPs in the implementation of core strategic interventions, and inform the effective deployment of new tools. CONCLUSION The prioritized research list is intended to serve as a key resource for informing OR and PE investments, thereby ensuring future investments focus on generating the evidence needed to strengthen national strategies and programme implementation and facilitating a more coordinated and impactful approach to malaria operational research.
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Affiliation(s)
- Roger Tine
- Université Cheikh Anta Diop, Dakar, Senegal
| | | | | | - Kyle Daniels
- PMI Insights Project/University of California, San Francisco Malaria Elimination Initiative, San Francisco, USA
| | | | - Cara Smith Gueye
- PMI Insights Project/University of California, San Francisco Malaria Elimination Initiative, San Francisco, USA
| | | | | | - Jimee Hwang
- U.S. President's Malaria Initiative, Malaria Branch, U.S. Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Evelyn Ansah
- University of Health and Allied Sciences, Accra, Ghana
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DANIS M. [Malaria today]. Med Trop Sante Int 2023; 3:mtsi.v3i2.2023.375. [PMID: 37525676 PMCID: PMC10387315 DOI: 10.48327/mtsi.v3i2.2023.375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 02/13/2023] [Indexed: 08/02/2023]
Abstract
Malaria, a parasitic disease the pathogen of which was discovered by Alphonse Laveran in 1880 in the blood of febrile patients, remains in 2022 the most frequent endemic disease in tropical and subtropical countries. In its latest "World Malaria Report" available in November 2021, the WHO deals in great detail with the data collected in the field in 2019-2020, their progression over the last 20 years, and the measures to be taken to try to better control this life-threatening endemic. The number of malaria cases is estimated at 232 million in 2019 in 87 endemic countries, down from 245 million in 2000. The WHO African Region alone accounts for 94% of cases and the most frequent and severe infections due to Plasmodium falciparum species. If children under the age of 5 are not treated promptly, they can die. Globally, the number of malaria deaths declined steadily over the period 2000-2019, from 897,000 in 2000 to 568,000 in 2019, with nearly 95% of deaths occurring in 31 countries, primarily in sub-Saharan Africa. In other WHO regions, including Southeast Asia, malaria deaths decreased by 74%, with 35,000 deaths in 2000 compared to 9,000 in 2019. Malaria can be controlled worldwide, and possibly eradicated, if public information campaigns are strengthened and sufficient funds are made available.
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Muema JM, Mutunga JM, Obonyo MA, Getahun MN, Mwakubambanya RS, Akala HM, Cheruiyot AC, Yeda RA, Juma DW, Andagalu B, Johnson JL, Roth AL, Bargul JL. Isoliensinine from Cissampelos pariera rhizomes exhibits potential gametocytocidal and anti-malarial activities against Plasmodium falciparum clinical isolates. Malar J 2023; 22:161. [PMID: 37208735 DOI: 10.1186/s12936-023-04590-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Accepted: 05/15/2023] [Indexed: 05/21/2023] Open
Abstract
BACKGROUND The unmet demand for effective malaria transmission-blocking agents targeting the transmissible stages of Plasmodium necessitates intensive discovery efforts. In this study, a bioactive bisbenzylisoquinoline (BBIQ), isoliensinine, from Cissampelos pariera (Menispermaceae) rhizomes was identified and characterized for its anti-malarial activity. METHODS Malaria SYBR Green I fluorescence assay was performed to evaluate the in vitro antimalarial activity against D6, Dd2, and F32-ART5 clones, and immediate ex vivo (IEV) susceptibility for 10 freshly collected P. falciparum isolates. To determine the speed- and stage-of-action of isoliensinine, an IC50 speed assay and morphological analyses were performed using synchronized Dd2 asexuals. Gametocytocidal activity against two culture-adapted gametocyte-producing clinical isolates was determined using microscopy readouts, with possible molecular targets and their binding affinities deduced in silico. RESULTS Isoliensinine displayed a potent in vitro gametocytocidal activity at mean IC50gam values ranging between 0.41 and 0.69 µM for Plasmodium falciparum clinical isolates. The BBIQ compound also inhibited asexual replication at mean IC50Asexual of 2.17 µM, 2.22 µM, and 2.39 µM for D6, Dd2 and F32-ART5 respectively, targeting the late-trophozoite to schizont transition. Further characterization demonstrated a considerable immediate ex vivo potency against human clinical isolates at a geometric mean IC50IEV = 1.433 µM (95% CI 0.917-2.242). In silico analyses postulated a probable anti-malarial mechanism of action by high binding affinities for four mitotic division protein kinases; Pfnek1, Pfmap2, Pfclk1, and Pfclk4. Additionally, isoliensinine was predicted to possess an optimal pharmacokinetics profile and drug-likeness properties. CONCLUSION These findings highlight considerable grounds for further exploration of isoliensinine as an amenable scaffold for malaria transmission-blocking chemistry and target validation.
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Affiliation(s)
- Jackson M Muema
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, Kenya.
- U.S. Army Medical Research Directorate-Africa (USAMRD-A), Centre for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya.
| | - James M Mutunga
- U.S. Army Medical Research Directorate-Africa (USAMRD-A), Centre for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
- Department of Biological Sciences, School of Pure and Applied Sciences, Mount Kenya University, Thika, Kenya
- School of Engineering Design, Technology and Professional Programs, Pennsylvania State University, University Park, PA, 16802, USA
| | - Meshack A Obonyo
- Department of Biochemistry and Molecular Biology, Egerton University, Egerton, Kenya
| | - Merid N Getahun
- International Centre of Insect Physiology and Ecology (Icipe), Nairobi, Kenya
| | | | - Hoseah M Akala
- U.S. Army Medical Research Directorate-Africa (USAMRD-A), Centre for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Agnes C Cheruiyot
- U.S. Army Medical Research Directorate-Africa (USAMRD-A), Centre for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Redemptah A Yeda
- U.S. Army Medical Research Directorate-Africa (USAMRD-A), Centre for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Dennis W Juma
- U.S. Army Medical Research Directorate-Africa (USAMRD-A), Centre for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Ben Andagalu
- U.S. Army Medical Research Directorate-Africa (USAMRD-A), Centre for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Jaree L Johnson
- U.S. Army Medical Research Directorate-Africa (USAMRD-A), Centre for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Amanda L Roth
- U.S. Army Medical Research Directorate-Africa (USAMRD-A), Centre for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Joel L Bargul
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, Kenya.
- International Centre of Insect Physiology and Ecology (Icipe), Nairobi, Kenya.
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da Silva Ferreira Lima AC, Galardo AKR, Müller JN, de Andrade Corrêa APS, Ribeiro KAN, Silveira GA, Hijjar AV, Soares da Roch Bauzer LG, Lima JBP. Evaluation of Long-lasting insecticidal nets (LLINs) for malaria control in an endemic area in Brazil. Parasit Vectors 2023; 16:162. [PMID: 37173754 PMCID: PMC10182611 DOI: 10.1186/s13071-023-05759-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 03/29/2023] [Indexed: 05/15/2023] Open
Abstract
BACKGROUND Most cases of malaria in Brazil are concentrated in the Amazon region. One of the vector control alternatives recommended by the WHO is the long-lasting insecticidal net (LLIN). This tool is used in the nine federal states of the Brazilian Legal Amazon, where LLINs are essential for reducing vector density and disease transmission as they prevent contact between the mosquito and the individual. The objective of this study was to evaluate the residuality and use of LLIN insecticides in different health regions in a city located in the Brazilian Amazon. METHODS A total of 17,027 LLINs were installed in the third, fifth and ninth health regions of the municipality of Porto Velho, Rondonia State, Brazil. The LLINs were of two types: Olyset (permethrin), for around the bed, and Interceptor (alphacypermethrin), for around hammocks. The residuality of 172 LLINs was evaluated using cone bioassays to verify the mortality rate of the mosquito Nyssorhynchus darlingi, over a period of 2 years. Structured questionnaires on the acceptance and use of LLINs were distributed to the participating population (n = 391), covering a total sample of 1147 mosquito nets. The mortality rate was evaluated both in terms of days after LLIN installation and the type of insecticide used. Statistical analyses were based on analysis of variance (ANOVA) and Chi-square and were performed using the SPSS statistical program. RESULTS For the Ny. darlingi mosquito, Interceptor-type LLINs showed residual efficacy, with mortality rates ≥ 80% during the 2-year study period, as determined by the WHO. In contrast, Olyset-type LLINs were associated with a reduction in mortality rates, with 76% and 45% mortality rates in the last two assessments, which occurred during the last 6 months of the study period. Based on the structured questionnaires, the acceptance rate, i.e. percentage of individuals accepting the permanence of the 1147 LLINs sampled, in the three health regions of Porto Velho was 93.8% (of 1076 LLINs). CONCLUSION The alphacypermethrin-impregnated LLIN was more effective than the LLIN impregnated with permethrin. The results indicate that the correct use of mosquito nets-and consequently the protection of the population-needs to be supported by health promotion actions. These initiatives are considered to be essential for the success of this vector control strategy. New studies that consider the monitoring of the placement of mosquito nets are necessary to provide effective support in the correct use of this methodology.
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Affiliation(s)
- Ana Cristina da Silva Ferreira Lima
- Laboratório de Entomologia Médica, Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá (IEPA), Macapá, Amapá, Brazil
- Laboratório de Fisiologia e Controle de Artrópodes Vetores, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Instituto Oswaldo Cruz FIOCRUZ, Rio de Janeiro, Brazil
| | - Allan Kardec Ribeiro Galardo
- Laboratório de Entomologia Médica, Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá (IEPA), Macapá, Amapá, Brazil
| | - Josiane Nogueira Müller
- Laboratório de Entomologia Médica, Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá (IEPA), Macapá, Amapá, Brazil.
- Laboratório de Fisiologia e Controle de Artrópodes Vetores, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
- Programa de Pós-Graduação em Medicina Tropical, Instituto Oswaldo Cruz FIOCRUZ, Rio de Janeiro, Brazil.
| | - Ana Paula Sales de Andrade Corrêa
- Laboratório de Entomologia Médica, Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá (IEPA), Macapá, Amapá, Brazil
- Laboratório de Fisiologia e Controle de Artrópodes Vetores, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Instituto Oswaldo Cruz FIOCRUZ, Rio de Janeiro, Brazil
| | | | | | | | | | - José Bento Pereira Lima
- Laboratório de Fisiologia e Controle de Artrópodes Vetores, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Instituto Oswaldo Cruz FIOCRUZ, Rio de Janeiro, Brazil
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Nnaji A, Ozdal MA. Perception and awareness towards malaria vaccine policy implementation in Nigeria by health policy actors. Malar J 2023; 22:111. [PMID: 36991411 PMCID: PMC10054212 DOI: 10.1186/s12936-023-04536-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 03/17/2023] [Indexed: 03/31/2023] Open
Abstract
BACKGROUND This study aimed to assess the perception and awareness of malaria vaccine policy implementation among health policy actors in Nigeria. METHODS A descriptive study was conducted to assess the opinions and perceptions of policy actors on the implementation of a vaccination programme against malaria in Nigeria. Descriptive statistics were carried out to study the characteristics of the population and the univariate analysis of the responses to questions presented to the participants. Multinomial logistic regression was conducted to evaluate the association between demographic characteristics and the responses. RESULTS The study revealed that malaria vaccine awareness was poor, with only 48.9% of the policy actors having previous knowledge of the malaria vaccine. The majority of participants (67.8%) declared that they were aware of the importance of vaccine policy in efforts to manage disease transmission. As the number of years of work experience of the participants increased, the odds of being more likely to be aware of the malaria vaccine increased [OR 2.491 (1.183-5.250), p value < 0.05]. CONCLUSION It is recommended that policy-makers develop methods of educating populations, increase awareness of the acceptability of the vaccine and ensure that an affordable malaria vaccine programme is implemented in the population.
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Affiliation(s)
- Adaugo Nnaji
- Institute of Graduate Studies and Research, European University of Lefke, Northern Cyprus, TR-10, Mersin, Turkey.
| | - Macide Artac Ozdal
- Faculty of Health Sciences, Department of Health Management, European University of Lefke, Northern Cyprus, TR-10, Mersin, Turkey
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Bofu RM, Santos EM, Msugupakulya BJ, Kahamba NF, Swilla JD, Njalambaha R, Kelly AH, Lezaun J, Christofides N, Okumu FO, Finda MF. The needs and opportunities for housing improvement for malaria control in southern Tanzania. Malar J 2023; 22:69. [PMID: 36849883 PMCID: PMC9972788 DOI: 10.1186/s12936-023-04499-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 02/16/2023] [Indexed: 03/01/2023] Open
Abstract
BACKGROUND Malaria disproportionately affects low-income households in rural communities where poor housing is common. Despite evidence that well-constructed and mosquito-proofed houses can reduce malaria risk, housing improvement is rarely included in malaria control toolboxes. This study assessed the need, magnitude, and opportunities for housing improvement to control malaria in rural Tanzania. METHODS A mixed-methods study was conducted in 19 villages across four district councils in southern Tanzania. A structured survey was administered to 1292 community members to assess need, perceptions, and opportunities for housing improvement for malaria control. Direct observations of 802 houses and surrounding environments were done to identify the actual needs and opportunities, and to validate the survey findings. A market survey was done to assess availability and cost of resources and services necessary for mosquito-proofing homes. Focus group discussions were conducted with key stakeholders to explore insights on the potential and challenges of housing improvement as a malaria intervention. RESULTS Compared to other methods for malaria control, housing improvement was among the best understood and most preferred by community members. Of the 735 survey respondents who needed housing improvements, a majority needed window screening (91.1%), repairs of holes in walls (79.4%), door covers (41.6%), closing of eave spaces (31.2%) and better roofs (19.0%). Community members invested significant efforts to improve their own homes against malaria and other dangers, but these efforts were often slow and delayed due to high costs and limited household incomes. Study participants suggested several mechanisms of support to improve their homes, including government loans and subsidies. CONCLUSION Addressing the need for housing improvement is a critical component of malaria control efforts in southern Tanzania. In this study, a majority of the community members surveyed needed modest modifications and had plans to work on those modifications. Without additional support, their efforts were however generally slow; households would take years to sufficiently mosquito-proof their houses. It is, therefore, crucial to bring together the key players across sectors to reduce barriers in malaria-proofing housing in endemic settings. These may include government subsidies or partnerships with businesses to make housing improvement more accessible and affordable to residents.
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Affiliation(s)
- Ramadhani M. Bofu
- grid.414543.30000 0000 9144 642XDepartment of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania ,grid.451346.10000 0004 0468 1595School of Life Sciences and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania ,Mpwapwa Institute of Health and Allied Sciences, The Ministry of Health, P.O. Box 743, Dodoma, Tanzania
| | - Ellen M. Santos
- grid.263857.d0000 0001 0816 4489Department of Applied Health, Southern Illinois University Edwardsville, Edwardsville, USA
| | - Betwel J. Msugupakulya
- grid.414543.30000 0000 9144 642XDepartment of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania ,grid.48004.380000 0004 1936 9764Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Najat F. Kahamba
- grid.414543.30000 0000 9144 642XDepartment of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania ,grid.8756.c0000 0001 2193 314XSchool of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G128QQ UK
| | - Joseph D. Swilla
- grid.451346.10000 0004 0468 1595School of Life Sciences and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania ,grid.8193.30000 0004 0648 0244Department of Molecular Biology and Biotechnology, University of Dar es Salaam, Dar es Salaam, Tanzania
| | - Rukiyah Njalambaha
- grid.414543.30000 0000 9144 642XDepartment of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania
| | - Ann H. Kelly
- grid.13097.3c0000 0001 2322 6764Department of Global Health and Social Medicine, King’s College London, London, UK
| | - Javier Lezaun
- grid.4991.50000 0004 1936 8948Institute for Science, Innovation, and Society, School of Anthropology and Museum Ethnography, University of Oxford, Oxford, UK
| | - Nicola Christofides
- grid.11951.3d0000 0004 1937 1135School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 1 Smuts Avenue, Braamfontein, Johannesburg, 2000 South Africa
| | - Fredros O. Okumu
- grid.414543.30000 0000 9144 642XDepartment of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania ,grid.451346.10000 0004 0468 1595School of Life Sciences and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania ,grid.8756.c0000 0001 2193 314XSchool of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G128QQ UK ,grid.11951.3d0000 0004 1937 1135School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 1 Smuts Avenue, Braamfontein, Johannesburg, 2000 South Africa
| | - Marceline F. Finda
- grid.414543.30000 0000 9144 642XDepartment of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania ,grid.451346.10000 0004 0468 1595School of Life Sciences and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania
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Rulisa A, van Kempen L, Hakizimana E, Koenraadt CJM. Local resource mobilization for malaria vector control among Rwandan rice farmers: a pilot study into the role of community ownership. J Health Popul Nutr 2023; 42:6. [PMID: 36691108 PMCID: PMC9872385 DOI: 10.1186/s41043-023-00345-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 01/11/2023] [Indexed: 01/25/2023]
Abstract
BACKGROUND Evidence suggests a vicious cycle between rice cultivation and malaria control in Rwanda. Rice fields offer an attractive breeding ground for malaria vectors, which increases the disease burden in rice farming communities, and, consequently, reduces productivity in the rice sector. Community-based larval source management in rice fields is propagated as a sustainable solution to break this cycle. A sense of agency and ownership of malaria control interventions, as well as the mobilization of resources at the local level, are often considered preconditions for success. However, an evidence gap exists regarding the interaction between the agentive and financial dimension of local sustainability. METHODS We conduct a larviciding pilot involving three groups; one group where rice farmers sprayed their fields under expert supervision, one group where rice farmers organised the larviciding campaign themselves, and a (non-sprayed) control group. We test whether the difference in agency between the intervention groups affects farmers' willingness-to-pay for a larviciding campaign. Willingness-to-pay is elicited in a contingent valuation exercise, more specifically a bidding game, and is assessed both before and after the pilot (n = 288). Difference-in-difference estimates are computed, using a propensity score matching technique. Supplementary data were collected in a survey and two focus group discussions for triangulation. RESULTS The high-agency (self-organised) group significantly outperforms the low-agency (expert-supervised) group in terms of maintaining its willingness to contribute financially. However, higher willingness-to-pay in the high-agency group does not appear to be driven by a stronger sense of ownership per se. The supplementary data indicate high levels of ownership in both treatment groups compared to the control group. A tentative explanation lies in diverging perceptions concerning the effectiveness of the pilot. CONCLUSIONS The study supports the idea that community-led organization of larval source management can prove instrumental in mobilizing finance for malaria control in low-income settings where rice production interferes with the fight against malaria. However, the causality is complex. Feelings of ownership do not appear the main driver of willingness-to-pay, at least not directly, which opens up the possibility of initiating community-driven malaria control interventions that promote the agentive and financial dimension of local sustainability simultaneously.
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Affiliation(s)
- Alexis Rulisa
- grid.5590.90000000122931605Department of Cultural Anthropology and Development Studies, and Radboud Social Cultural Research, Radboud University, 6525 XZ Nijmegen, The Netherlands
| | - Luuk van Kempen
- grid.5590.90000000122931605Department of Cultural Anthropology and Development Studies, and Radboud Social Cultural Research, Radboud University, 6525 XZ Nijmegen, The Netherlands
| | - Emmanuel Hakizimana
- grid.452755.40000 0004 0563 1469Malaria and Other Parasitic Diseases Division, Rwanda Biomedical Center, 7162 Kigali, Rwanda
| | - Constantianus J. M. Koenraadt
- grid.4818.50000 0001 0791 5666Laboratory of Entomology, Wageningen University & Research, 6708 Wageningen, The Netherlands
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Koenker H, Worges M, Yukich J, Gitanya P, Chacky F, Lazaro S, Mwalimu CD, Aaron S, Ibrahim R, Abbas F, Khamis M, Mwingizi D, Dadi D, Selby A, Serbantez N, Msangi L, Loll D, Kamala B. Estimating population ITN access at council level in Tanzania. Malar J 2023; 22:4. [PMID: 36604693 PMCID: PMC9815063 DOI: 10.1186/s12936-022-04432-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 12/24/2022] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Since 2013, the National Malaria Control Programme in mainland Tanzania and the Zanzibar Malaria Elimination Programme have implemented mass insecticide-treated net (ITN) distribution campaigns, routine ITN distribution to pregnant women and infants, and continuous distribution through primary schools (mainland) and community leaders (Zanzibar) to further malaria control efforts. Mass campaigns are triggered when ITN access falls below 40%. In this context, there is a need to monitor ITN access annually to assess whether it is below threshold and inform quantification of ITNs for the following year. Annual estimates of access are needed at the council level to inform programmatic decision-making. METHODS An age-structured stock and flow model was used to predict annual net crops from council-level distribution data in Tanzania from 2012 to 2020 parameterized with a Tanzania-specific net median lifespan of 2.15 years. Annual nets-per-capita (NPC) was calculated by dividing each annual net crop by mid-year council projected population. A previously fit nonparametric conditional quantile function for the proportion of the population with access to an ITN (ITN access) as a function of NPC was used to predict ITN access at the council level based on the predicted NPC value. These estimates were compared to regional-level ITN access from large household surveys. RESULTS For regions with the same ITN strategy for all councils, predicted council-level ITN access was consistent with regional-level survey data for 79% of councils. Regions where ITN strategy varied by council had regional estimates of ITN access that diverged from the council-specific estimates. Predicted ITN access reached 60% only when "nets issued as a percentage of the council population" (NPP) exceeded 15%, and approached 80% ITN access when NPP was at or above 20%. CONCLUSION Modelling ITN access with country-specific net decay rates, council-level population, and ITN distribution data is a promising approach to monitor ITN coverage sub-regionally and between household surveys in Tanzania and beyond.
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Affiliation(s)
- Hannah Koenker
- USAID Tanzania Vector Control Activity, Tropical Health, Baltimore, MD USA
| | - Matt Worges
- USAID Tanzania Vector Control Activity, Tropical Health, New Orleans, LA USA
| | - Joshua Yukich
- USAID Tanzania Vector Control Activity, Tropical Health, New Orleans, LA USA ,grid.265219.b0000 0001 2217 8588Tulane University, New Orleans, LA USA
| | - Peter Gitanya
- National Malaria Control Programme, Ministry of Health, Dodoma, Tanzania
| | - Frank Chacky
- National Malaria Control Programme, Ministry of Health, Dodoma, Tanzania
| | - Samwel Lazaro
- National Malaria Control Programme, Ministry of Health, Dodoma, Tanzania
| | | | - Sijenunu Aaron
- National Malaria Control Programme, Ministry of Health, Dodoma, Tanzania
| | - Raya Ibrahim
- Zanzibar Malaria Elimination Programme, Zanzibar, Tanzania
| | - Faiza Abbas
- Zanzibar Malaria Elimination Programme, Zanzibar, Tanzania
| | - Mwinyi Khamis
- Zanzibar Malaria Elimination Programme, Zanzibar, Tanzania
| | - Deodatus Mwingizi
- USAID Tanzania Vector Control Activity, Johns Hopkins University School of Public Health Center for Communication Programs, Dar Es Salaam, Tanzania
| | - David Dadi
- USAID Tanzania Vector Control Activity, Johns Hopkins University School of Public Health Center for Communication Programs, Dar Es Salaam, Tanzania
| | - Ato Selby
- USAID Tanzania Vector Control Activity, Johns Hopkins University School of Public Health Center for Communication Programs, Dar Es Salaam, Tanzania
| | - Naomi Serbantez
- U.S. President’s Malaria Initiative, Dar Es Salaam, Tanzania
| | - Lulu Msangi
- U.S. President’s Malaria Initiative, Dar Es Salaam, Tanzania
| | - Dana Loll
- grid.21107.350000 0001 2171 9311USAID Tanzania Vector Control Activity, Johns Hopkins University School of Public Health Center for Communication Programs, Baltimore, MD USA
| | - Benjamin Kamala
- USAID Tanzania Vector Control Activity, Johns Hopkins University School of Public Health Center for Communication Programs, Dar Es Salaam, Tanzania
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Ngonghala CN. Assessing the impact of insecticide-treated nets in the face of insecticide resistance on malaria control. J Theor Biol 2022; 555:111281. [PMID: 36154815 DOI: 10.1016/j.jtbi.2022.111281] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 09/01/2022] [Accepted: 09/17/2022] [Indexed: 01/14/2023]
Abstract
The mosquito-borne disease, malaria, continues to impose a devastating health and economic burden worldwide. In malaria-endemic areas, insecticide-treated nets (ITNs) have been useful in curtailing the burden of the disease. However, mosquito resistance to insecticides, decay in ITN efficacy, net attrition, etc., undermine the effectiveness of ITNs in combatting malaria. In this study, mathematical models that account for asymptomatic infectious humans (through a partially immune class or a separate asymptomatic infectious class), insecticide resistance, and decay in ITN efficacy are proposed and analyzed. Analytical and numerical results of the models when ITN efficacy is constant show that there are parameter regimes for which a backward bifurcation occurs. Local and global sensitivity analyses are performed to identify parameters (some of which are potential targets for disease control) with the most significant influence on the control reproduction (Rc) and disease prevalence. These influential parameters include the maximum biting rate of resistant mosquitoes, ITN coverage, initial ITN efficacy against sensitive mosquitoes, the probability that an infectious mosquito (human) infects a susceptible human (mosquito), and the rate at which adult mosquitoes develop (lose) resistance to insecticides. Simulations of the models show that accounting for asymptomatic infectious humans through a separate class, or not accounting for the decay in ITN efficacy leads to an underestimation of disease burden. In particular, if the initial efficacy of ITNs against sensitive and resistance mosquitoes is 96%, the minimum ITN coverage required to reduce Rc below one (and hence, contain malaria) is approximately 11% (27%) lower when ITN efficacy is averaged (constant) for a model with a separate asymptomatic class. For the model with a partially immune class and decaying ITN efficacy, reducing Rc below one is impossible even if the entire populace uses ITNs. The study shows that replacing ITNs before their prescribed lifespans, or designing ITNs with longer lifespans is important for malaria control. Furthermore, the study shows that piperonyl butoxide (PBO) ITNs (which inhibit or reverse insecticide resistance) outperform regular ITNs in malaria control. Hence, prospects for effectively controlling malaria are enhanced by widespread use of high quality ITNs (e.g. PBO ITNs), especially if the useful lifespans of the ITNs are long enough and the ITNs are replaced before the end of their useful lifespans.
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Affiliation(s)
- Calistus N Ngonghala
- Department of Mathematics, University of Florida, 1400 Stadium Rd, Gainesville, FL 32611, United States of America; Emerging Pathogens Institute, University of Florida, 2055 Mowry Rd, Gainesville, FL 32610, United States of America; Center for African Studies, University of Florida, 427 Grinter Hall 1523 Union Rd, Gainesville, FL 32611, United States of America.
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Akello AR, Byagamy JP, Etajak S, Okadhi CS, Yeka A. Factors influencing consistent use of bed nets for the control of malaria among children under 5 years in Soroti District, North Eastern Uganda. Malar J 2022; 21:363. [PMID: 36461059 PMCID: PMC9716664 DOI: 10.1186/s12936-022-04396-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 11/21/2022] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND The use of insecticide-treated bed nets has been proven to be effective in reducing malaria transmission in highly endemic areas. Use of long-lasting insecticidal nets (LLINs) has been embraced by many malaria endemic countries. LLINs are up to 95% effective in inhibiting blood feeding, when used consistently even after 7 years. The challenge, however, is enhancing their consistent use, especially by the most vulnerable groups (children under 5 years and pregnant women). The study established factors associated with consistent use of bed nets for malaria control among children under 5 years in Soroti district. METHODS The study employed a cross-sectional design, with multi-stage sampling of households. A total of 400 households (HH) were sampled and the HH head in each household interviewed. Key informant interviews (KIIs) were conducted with 7 key informants who were knowledgeable on the subject matter. Data analysis was done using SPSS 17.0 at Univariate, Bivariate and Multivariable levels; after entry and cleaning. Key informants' data were summarized manually; verbatim quotes and text used to reinforce quantitative data in line with objectives. RESULTS Only 56.8% of the 690 children under 5 years used bed nets consistently. The factors affecting consistent bed net use were age of the child, their use of bed nets the previous night, occupation of caretaker, respondents' perceived susceptibility, perceived risk of getting malaria, size and shape of the bed nets. Rectangular nets were difficult to hang daily in huts according to most key informants. CONCLUSION Consistent bed net use among under fives is still below the RBM target of 85% by 2015 and can be enhanced by providing conical bed nets and setting aside a health education programme to emphasize the effectiveness of even one mosquito in spreading malaria at night to the entire household and ability of bed nets to stop transmission better than other methods.
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Affiliation(s)
- Anne Ruth Akello
- Department of Public Health, Faculty of Health Sciences, Lira University, Lira, Uganda ,grid.11194.3c0000 0004 0620 0548Deprtment of Disease Control and Environmental Health, School of Public Health, Makerere University, Kampala, Uganda
| | - John Paul Byagamy
- Department of Public Health, Faculty of Health Sciences, Lira University, Lira, Uganda
| | - Samuel Etajak
- grid.11194.3c0000 0004 0620 0548Deprtment of Disease Control and Environmental Health, School of Public Health, Makerere University, Kampala, Uganda
| | | | - Adoke Yeka
- grid.11194.3c0000 0004 0620 0548Deprtment of Disease Control and Environmental Health, School of Public Health, Makerere University, Kampala, Uganda
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Graboyes M, Meta J, Clarke R. Mazingira and the malady of malaria: Perceptions of malaria as an environmental disease in contemporary Zanzibar. Stud Hist Philos Sci 2022; 95:134-144. [PMID: 36027656 DOI: 10.1016/j.shpsa.2022.07.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 02/25/2022] [Accepted: 07/28/2022] [Indexed: 06/15/2023]
Abstract
This paper addresses how contemporary Zanzibaris perceive the relationship between the mazingira (roughly translated as "environment") and the malady of malaria. More broadly, this article presents data exploring Zanzibari conceptions of the mazingira, the relationship between the mazingira and malaria, and who Zanzibaris believe are responsible for acting on, or for, the mazingira in regards to malaria. We use the biomedical disease malaria-and the local syncretic understanding of it, which we recognize by referring to it as the "malady of malaria"-as a lens to investigate Zanzibari conceptions of the mazingira. We highlight the need to integrate local forms of knowledge, which we refer to as vernacular knowledge. 50 interviews show that Zanzibaris believe the mazingira can be modified in positive ways to cleaner, safer spaces that will also reduce malaria levels. People expressed widespread agreement that there is a clear relationship between the mazingira and the malady of malaria, though they differed in what exactly the relationship was.
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Oladipo HJ. Increasing challenges of malaria control in sub-Saharan Africa: Priorities for public health research and policymakers. Ann Med Surg (Lond) 2022; 81:104366. [PMID: 36046715 PMCID: PMC9421173 DOI: 10.1016/j.amsu.2022.104366] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 08/11/2022] [Indexed: 11/21/2022] Open
Abstract
The ever-increasing cases and mortality due to malaria remains one of the most important public health threats, especially in sub-Saharan Africa-where this burden is considerably high. In 2020, sub-Saharan Africa accounted for about 95% of all cases and 96% of all malaria deaths with about 80% of these deaths reported in children under the age of 5. This review, adopting a public health focus, aimed to understand the challenges of malaria control in sub-Saharan Africa despite ongoing public health interventions. Our review highlights two important findings. First, the increasing resistance of malaria parasites to artemisinin-based combination therapy (ACT) and its partner drugs coupled with increased vector resistance to pyrethroids and insecticides is reversing the progress of public health interventions in keeping malaria under control. Second, the wanning for the efficacy of the WHO-approved vaccine i.e. RTS,S from 60 to 70% following 18 months of observation, and its short-term availability remains an impediment to achieving the WHO target of producing malaria vaccines with more than 75% efficacy by 2030. Our findings underline the need to reassess research priorities with a focus on vaccine production in sub-Saharan Africa. Furthermore, African governments and policymakers must be committed to invest both the political and financial capital in vaccine production and distribution.
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Koenker H, Worges M, Kamala B, Gitanya P, Chacky F, Lazaro S, Mwalimu CD, Aaron S, Mwingizi D, Dadi D, Selby A, Serbantez N, Msangi L, Loll D, Yukich J. Annual distributions of insecticide-treated nets to schoolchildren and other key populations to maintain higher ITN access than with mass campaigns: a modelling study for mainland Tanzania. Malar J 2022; 21:246. [PMID: 36028866 PMCID: PMC9417077 DOI: 10.1186/s12936-022-04272-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 08/16/2022] [Indexed: 11/12/2022] Open
Abstract
Background Since 2013, the National Malaria Control Programme in mainland Tanzania has deployed annual distributions of insecticide-treated nets (ITNs) through primary schools to maintain ITN access and use. This School Net Programme (SNP) is slated to be used throughout mainland Tanzania by 2023. This modelling study projects ITN access under different ITN distribution strategies and quantification approaches. Methods A stock and flow model with a Tanzania-specific ITN decay rate was used to calculate annual net crops for four different ITN distribution strategies, varying quantification approaches within each strategy. Annual nets-per-capita (NPC) was derived from net crop and a standardized population projection. Nonparametric conditional quartile functions for the proportion of the population with access to an ITN (ITN access) as a function of NPC were used to predict ITN access and its variability. The number of ITNs required under the varying quantification approaches for the period 2022–2030 was calculated. Results Annual SNP quantified using a “population times 15%” approach maintained ITN access between 80 and 90%, when combined with reproductive and child health (RCH) ITN distribution, requiring 133.2 million ITNs. The same strategy quantified with “population times 22%” maintained ITN access at or above 90%, requiring 175.5 million ITNs. Under 5-year mass campaigns with RCH distribution for pregnant women and infants, ITN access reached 90% post-campaign and fell to 27–35% in the 4th year post-campaign, requiring 120.5 million ITNs over 8 years. 3-yearly mass campaigns with RCH reached 100% ITN access post-campaign and fell to 70% in the 3rd year post-campaign, requiring 154.4 million ITNs. Conclusion Given an ITN retention time in Tanzania of 2.15 years, the model predicts that mass campaigns conducted every 3 years in mainland Tanzania will not maintain ITN access at target levels of 80%, even with strong RCH channels. Mainland Tanzania can however expect to maintain ITN access at 80% or above by quantifying SNP using “population × 15%”, in addition to RCH ITN delivery. This strategy requires 14% fewer ITNs than a 3-year campaign strategy while providing more consistent ITN coverage. Meeting the targets of 80% ITN use would require maintaining 90% ITN access, achievable using a “population times 22%” quantification approach for SNP. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04272-w.
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Affiliation(s)
- Hannah Koenker
- USAID Tanzania Vector Control Activity, Tropical Health, Baltimore, MD, USA.
| | - Matt Worges
- USAID Tanzania Vector Control Activity, Tropical Health, New Orleans, LA, USA
| | - Benjamin Kamala
- USAID Tanzania Vector Control Activity, Johns Hopkins University School of Public Health Center for Communication Programmes, Dar es Salaam, Tanzania
| | - Peter Gitanya
- National Malaria Control Programme, Ministry of Health, Dodoma, Tanzania
| | - Frank Chacky
- National Malaria Control Programme, Ministry of Health, Dodoma, Tanzania
| | - Samwel Lazaro
- National Malaria Control Programme, Ministry of Health, Dodoma, Tanzania
| | | | - Sijenunu Aaron
- National Malaria Control Programme, Ministry of Health, Dodoma, Tanzania
| | - Deodatus Mwingizi
- USAID Tanzania Vector Control Activity, Johns Hopkins University School of Public Health Center for Communication Programmes, Dar es Salaam, Tanzania
| | - David Dadi
- USAID Tanzania Vector Control Activity, Johns Hopkins University School of Public Health Center for Communication Programmes, Dar es Salaam, Tanzania
| | - Ato Selby
- USAID Tanzania Vector Control Activity, Johns Hopkins University School of Public Health Center for Communication Programmes, Dar es Salaam, Tanzania
| | | | - Lulu Msangi
- US President's Malaria Initiative, Dar es Salaam, Tanzania
| | - Dana Loll
- USAID Tanzania Vector Control Activity, Johns Hopkins University School of Public Health Center for Communication Programs, Baltimore, MD, USA
| | - Joshua Yukich
- USAID Tanzania Vector Control Activity, Tropical Health, New Orleans, LA, USA
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19
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Njoroge MM, Hiscox A, Saddler A, Takken W, van Loon JJA, Fillinger U. Less is more: repellent-treated fabric strips as a substitute for full screening of open eave gaps for indoor and outdoor protection from malaria mosquito bites. Parasit Vectors 2022; 15:259. [PMID: 35858931 PMCID: PMC9297553 DOI: 10.1186/s13071-022-05384-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 07/06/2022] [Indexed: 11/10/2022] Open
Abstract
Background Providing protection from malaria vector bites, both indoors and outdoors, is crucial to curbing malaria parasite transmission. Screening of house entry points, especially with incorporated insecticides, confers significant protection but remains a costly and labour-intensive application. Use of spatial repellents has shown promise in creating areas of protection in peri-domestic areas. Methods This study aimed at comparing the protection provided by transfluthrin-treated and untreated complete screens over open eave gaps with incomplete transfluthrin-treated eave strips as a potential replacement for a full screen. Human landing catches were implemented independently inside and outside an experimental hut under controlled semi-field conditions, with insectary-reared Anopheles arabiensis mosquitoes. Results The odds of a female mosquito finding a human volunteer indoors and attempting to bite were similar whether the eaves were completely open or there was an untreated fabric strip fixed around the eaves. However, when the eave gap was completely screened without insecticide, the odds of receiving a bite indoors were reduced by 70% (OR 0.30, 95% CI 0.20–0.47). Adding transfluthrin to the full screen, further increased the protection indoors, with the odds of receiving a bite reduced by 92% (0.08, 95% CI 0.04–0.16) compared to the untreated screen. Importantly, the same protection was conferred when only a narrow transfluthrin-treated fabric strip was loosely fixed around the eave gap (OR 0.07, 95% CI 0.04–0.13). The impact of the transfluthrin treatment on outdoor biting was correlated with evening temperatures during the experiments. At lower evening temperatures, a transfluthrin-treated, complete screen provided moderate and variable protection from bites (OR 0.62, 95% CI 0.37–1.03), whilst at higher evening temperatures the odds of receiving a bite outdoors was over four times lower in the presence of transfluthrin, on either a full screen (OR 0.22 95% 0.12–0.38) or a fabric strip (OR 0.25, 95% 0.15–0.42), than when no treatment was present. Conclusion The findings suggest that transfluthrin-treated fabric strips can provide a substitute for complete eave screens. They are a simple, easy-to-handle tool for protecting people from malaria mosquito bites indoors and potentially around the house in climatic areas where evening and night-time temperatures are relatively high.
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Affiliation(s)
- Margaret Mendi Njoroge
- International Centre of Insect Physiology and Ecology (icipe), Human Health Theme, P.O. Box 30772-00100, Nairobi, Kenya. .,Wageningen University & Research, Laboratory of Entomology, P.O. Box 16, 6700 AA, Wageningen, The Netherlands.
| | - Alexandra Hiscox
- Wageningen University & Research, Laboratory of Entomology, P.O. Box 16, 6700 AA, Wageningen, The Netherlands.,ARCTEC, London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Adam Saddler
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Socinstrasse 57, 4051 833, Basel, Switzerland.,Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania.,Malaria Atlas Project, Telethon Kids Institute, 15 Hospital Ave, Nedlands, Perth, WA, 6009, Australia
| | - Willem Takken
- Wageningen University & Research, Laboratory of Entomology, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
| | - Joop J A van Loon
- Wageningen University & Research, Laboratory of Entomology, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
| | - Ulrike Fillinger
- International Centre of Insect Physiology and Ecology (icipe), Human Health Theme, P.O. Box 30772-00100, Nairobi, Kenya
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20
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Edwards HM, Sarwar R, Mahmud P, Emmanuel S, Maxwell K, Tibenderana JK. The private sector market for malaria rapid diagnostic tests in Nigeria: results of the 2018 market survey. Malar J 2022; 21:190. [PMID: 35710474 DOI: 10.1186/s12936-022-04209-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 05/30/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND To avoid misuse of anti-malarials, correct diagnosis of fever prior to drug prescription is essential. Presumptive treatment in the private healthcare sector is a concern in Nigeria, where availability of affordable artemisinin-based combination therapy (ACT) is high following the implementation of subsidy schemes from 2010 to 2017. Similar subsidies have not, however, been implemented for malaria rapid diagnostic tests (RDTs). A market survey in 2018 predominantly designed to assess the ACT market in the private sector also collected data related to RDTs, results of which are presented herein. METHODS A 2018 market survey consisted of (i) an outlet survey targeting private pharmacies and Proprietary and Patent Medicine Vendors (PPMVs) across different regions of Nigeria to assess supply-side market factors related to availability of RDTs (defined as having stock available for purchase at the time of the survey) and (ii) a household survey to determine demand-side factors related to knowledge of RDTs, healthcare-seeking practices and affordability. RESULTS Availability of RDTs at the time of the survey was low in both outlet types and significantly lower in PPMVs (22.1%, 95% CI) among pharmacies versus (13.6%, 95% CI) among PPMVs (p < 0.01). Reasons for not restocking RDTs included low demand and no supply. The majority of households diagnose malaria based on experience, while one-third would visit a PPMV or pharmacy. Half of households had heard of RDTs (48.4%) and 38.6% thought they were affordable. CONCLUSIONS Low availability of RDTs among PPMVs and pharmacies may be attributed to lack of demand, supply-side issues and cost. Increasing household knowledge of RDTs may aid increasing demand, while subsidized RDTs may address supply and price issues. Addressing the deficit in RDT provision is important for targeting of ACT medicines.
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21
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Naserrudin NA, Monroe A, Culleton R, Hod R, Jeffree MS, Ahmed K, Hassan MR. Reimagining zoonotic malaria control in communities exposed to Plasmodium knowlesi infection. J Physiol Anthropol 2022; 41:14. [PMID: 35413881 PMCID: PMC9004057 DOI: 10.1186/s40101-022-00288-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 03/31/2022] [Indexed: 12/21/2022] Open
Abstract
Plasmodium knowlesi malaria infection in humans has been reported throughout southeast Asia. The communities at risk are those living in areas where Macaque monkeys and Anopheles mosquito are present. Zoonotic malaria control is challenging due to the presence of the reservoir host and the possibility of human-vector-human transmission. Current control measures, including insecticide-treated nets (ITNs) and indoor residual spraying (IRS), are insufficient to address this threat due to gaps in protection associated with outdoor and early evening vector biting and social and economic activities, such as agricultural and forest work. Understanding the challenges faced by affected communities in preventing mosquito bites is important for reducing disease transmission. This opinion paper discusses opportunities to improve P. knowlesi malaria control through understanding the challenges faced by communities at risk and increasing community engagement and ownership of control measures. The paper highlights this issue by describing how the concept of reimagining malaria can be adapted to zoonotic malaria control measures including identifying current gaps in vector control, understanding interactions between environmental, economic, and human behavioral factors, and increasing community participation in and ownership of control measures.
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Affiliation(s)
- Nurul Athirah Naserrudin
- Department of Community Health, Faculty of Medicine, Universiti Kebangsaan Malaysia, Cheras, Kuala Lumpur, Malaysia.,Borneo Medical and Health Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia, Kota Kinabalu, Sabah, Malaysia.,Sabah State Health Department, Ministry of Health, Kota Kinabalu, Malaysia
| | - April Monroe
- Johns Hopkins Center for Communication Programs, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - Richard Culleton
- Department of Molecular Parasitology, Proteo-Science Centre, Ehime University, Matsuyama, Japan
| | - Rozita Hod
- Department of Community Health, Faculty of Medicine, Universiti Kebangsaan Malaysia, Cheras, Kuala Lumpur, Malaysia
| | - Muhammad Saffree Jeffree
- Borneo Medical and Health Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia, Kota Kinabalu, Sabah, Malaysia.,Department of Public Health, Universiti Malaysia Sabah, Kota Kinabalu, Malaysia
| | - Kamruddin Ahmed
- Borneo Medical and Health Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia, Kota Kinabalu, Sabah, Malaysia.,Department of Public Health, Universiti Malaysia Sabah, Kota Kinabalu, Malaysia
| | - Mohd Rohaizat Hassan
- Department of Community Health, Faculty of Medicine, Universiti Kebangsaan Malaysia, Cheras, Kuala Lumpur, Malaysia.
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22
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Krezanoski PJ, Roh ME, Rek J, Nankabirwa JI, Arinaitwe E, Staedke SG, Nayiga S, Hsiang MS, Smith D, Kamya M, Dorsey G. Marked reduction in antibiotic usage following intensive malaria control in a cohort of Ugandan children. BMC Med 2021; 19:294. [PMID: 34844601 PMCID: PMC8630830 DOI: 10.1186/s12916-021-02167-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 10/21/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Intensive malaria control may have additional benefits beyond reducing the incidence of symptomatic malaria. We compared antibiotic treatment of children before and after the implementation of highly effective malaria control interventions in Tororo, a historically high transmission area of Uganda. METHODS Two successive cohorts of children, aged 0.5 to 10 years, were followed from September 2011 to October 2019 in a dedicated study clinic. Universal distribution of long-lasting insecticidal nets was conducted in 2013 and 2017. Sustained indoor residual spraying of insecticide (IRS) was initiated in December 2014. Generalized linear mixed-effects models were used to compare the incidence of antimalarial and antibiotic treatments before and after vector control measures were implemented. RESULTS Comparing the period prior to the implementation of IRS to the period after IRS had been sustained for 4-5 years, the adjusted incidence of malaria treatments decreased from 2.68 to 0.05 per person-year (incidence rate ratio [IRR] = 0.02, 95% CI 0.01-0.03, p < 0.001), and the adjusted incidence of antibiotic treatments decreased from 4.14 to 1.26 per person-year (IRR = 0.30, 95% CI 0.27-0.34, p < 0.001). The reduction in antibiotic usage was primarily associated with fewer episodes of symptomatic malaria and fewer episodes of fever with sub-microscopic parasitemia, both of which were frequently treated with antibiotics. CONCLUSIONS In a historically high transmission setting, the implementation of highly effective vector control interventions was followed by a marked reduction in antibiotic treatment of children. This added benefit of malaria control could have important implications for antibiotic prescribing practices, efforts to curtail antimicrobial resistance, and health system costs.
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Affiliation(s)
- Paul J Krezanoski
- University of California, 1001 Potrero Avenue, San Francisco, CA, 94118, USA.
| | - Michelle E Roh
- University of California, 1001 Potrero Avenue, San Francisco, CA, 94118, USA
| | - John Rek
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Joaniter I Nankabirwa
- Infectious Diseases Research Collaboration, Kampala, Uganda.,Makerere University College of Health Sciences, Kampala, Uganda
| | | | | | - Susan Nayiga
- Infectious Diseases Research Collaboration, Kampala, Uganda.,London School of Hygiene and Tropical Medicine, London, UK
| | - Michelle S Hsiang
- University of California, 1001 Potrero Avenue, San Francisco, CA, 94118, USA
| | | | - Moses Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda.,Makerere University College of Health Sciences, Kampala, Uganda
| | - Grant Dorsey
- University of California, 1001 Potrero Avenue, San Francisco, CA, 94118, USA
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23
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Galactionova K, Smith TA, Penny MA. Insights from modelling malaria vaccines for policy decisions: the focus on RTS,S. Malar J 2021; 20:439. [PMID: 34794430 PMCID: PMC8600337 DOI: 10.1186/s12936-021-03973-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 11/04/2021] [Indexed: 11/17/2022] Open
Abstract
Mathematical models are increasingly used to inform decisions throughout product development pathways from pre-clinical studies to country implementation of novel health interventions. This review illustrates the utility of simulation approaches by reviewing the literature on malaria vaccine modelling, with a focus on its link to the development of policy guidance for the first licensed product, RTS,S/AS01. The main contributions of modelling studies have been in inferring the mechanism of action and efficacy profile of RTS,S; to predicting the public health impact; and economic modelling mainly comprising cost-effectiveness analysis. The value of both product-specific and generic modelling of vaccines is highlighted.
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Affiliation(s)
- Katya Galactionova
- Swiss Tropical and Public Health Institute, 4051, Basel, Switzerland.,University of Basel, 4001, Basel, Switzerland.,European Center of Pharmaceutical Medicine, Brombacherstrasse 5, 4057, Basel, Switzerland
| | - Thomas A Smith
- Swiss Tropical and Public Health Institute, 4051, Basel, Switzerland. .,University of Basel, 4001, Basel, Switzerland.
| | - Melissa A Penny
- Swiss Tropical and Public Health Institute, 4051, Basel, Switzerland.,University of Basel, 4001, Basel, Switzerland
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24
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Tarekegn M, Tekie H, Dugassa S, Wolde-Hawariat Y. Malaria prevalence and associated risk factors in Dembiya district, North-western Ethiopia. Malar J 2021; 20:372. [PMID: 34535130 DOI: 10.1186/s12936-021-03906-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 09/06/2021] [Indexed: 11/10/2022] Open
Abstract
Background Ethiopia embarked on combating malaria with an aim to eliminate malaria from low transmission districts by 2030. A continuous monitoring of malaria prevalence in areas under elimination settings is important to evaluate the status of malaria transmission and the effectiveness of the currently existing malaria intervention strategies. The aim of this study was to assess the prevalence of malaria and associated risk factors in selected areas of Dembiya district. Methods A cross-sectional parasitological and retrospective survey was conducted in the two localities of Dembiya District, selected based on their long standing history of implementing malaria prevention and elimination strategies. Thin and thick blood smears collected from 735 randomly selected individuals between October and December, 2018 were microscopically examined for malaria parasites. Six years (2012–2017) retrospective malaria data was collected from the medical records of the health centres. Structured questionnaires were prepared to collect information about the socio-economic data of the population. Logistic regression analysis was used to determine a key risk factor explaining the prevalence of malaria. The data were analysed using SPSS version 20 and p ≤ 0.05 were considered statistically significant. Results The 6-year retrospective malaria prevalence trend indicates an overall malaria prevalence of 22.4%, out of which Plasmodium falciparum was the dominant species. From a total of 735 slides examined for the presence of malaria parasites, 3.5% (n = 26) were positive for malaria parasites, in which P. falciparum was more prevalent (n = 17; 2.3%), Plasmodium vivax (n = 5; 0.7%), and mixed infections (n = 4; 0.5%). Males were 2.6 times more likely to be infected with malaria than females (AOR = 2.6; 95% CI 1.0, 6.4), and individuals with frequent outdoor activity were 16.4 times more vulnerable than individuals with limited outdoor activities (AOR = 16.4, 95% CI 1.8, 147.9). Furthermore, awareness about malaria transmission was significantly associated with the prevalence of malaria. Conclusions Malaria is still a public health problem in Dembiya district irrespective of the past and existing vector control interventions. Therefore, the authorities should work on designing alternative intervention strategies targeting outdoor malaria transmission and improving community awareness about malaria transmission and control methods in the study area. For this, continuous monitoring of vectors’ susceptibility, density, and behaviour is very important in such areas.
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25
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Charlwood JD, Andegiorgish AK, Asfaha YE, Tekle Weldu L, Petros F, Legese L, Afewerki R, Mihreteab S, LeClair C, Kampango A. Novel sampling methods for monitoring Anopheles arabiensis from Eritrea. PeerJ 2021; 9:e11497. [PMID: 34322315 PMCID: PMC8297471 DOI: 10.7717/peerj.11497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 04/30/2021] [Indexed: 01/03/2023] Open
Abstract
Background Studies comparing novel collection methods for host seeking and resting mosquitoes A. arabiensis were undertaken in a village in Eritrea. Techniques included an odor baited trap, a novel tent-trap, human landing collection and three methods of resting collection. A technique for the collection of mosquitoes exiting vegetation is also described. Pre-gravid rates were determined by dissection of host seeking insects and post-prandial egg development among insects collected resting. Results Overall 5,382 host-seeking, 2,296 resting and 357 A. arabiensis exiting vegetation were collected. The Furvela tent-trap was the most efficient, risk-free method for the collection of outdoor host-seeking insects, whilst the Suna trap was the least effective method. Mechanical aspirators (the CDC backpack or the Prokopack aspirator) were superior to manual aspiration in a dark shelter but there was no advantage over manual aspiration in a well-lit one. An estimated two-thirds of newly-emerged mosquitoes went through a pre-gravid phase, feeding twice before producing eggs. Mosquitoes completed gonotrophic development in a dark shelter but left a well-lit shelter soon after feeding. One blood-fed female marked in the village was recaptured 2 days after release exiting vegetation close to the oviposition site and another, shortly after oviposition, attempting to feed on a human host 3 days after release. Exit rates of males from vegetation peaked 3 min after the initial male had left. Unfed and gravid females exited approximately 6 min after the first males. Conclusions Furvela tent-traps are suitable for the collection of outdoor biting A. arabiensis in Eritrea whilst the Prokopack sampler is the method of choice for the collection of resting insects. Constructing well-lit, rather than dark, animal shelters, may encourage otherwise endophilic mosquitoes to leave and so reduce their survival and hence their vectorial capacity.
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Affiliation(s)
- Jacques D Charlwood
- Epidemiology and Public Health, College of Health Sciences, Asmara, Eritrea.,Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Lisbon, Portugal
| | - Amanuel Kidane Andegiorgish
- Epidemiology and Public Health, College of Health Sciences, Asmara, Eritrea.,Department of Epidemiology and Biostatistics, Xi'an Jiaotong University, Shaanxi, China
| | | | - Liya Tekle Weldu
- Epidemiology and Public Health, College of Health Sciences, Asmara, Eritrea
| | - Feven Petros
- Epidemiology and Public Health, College of Health Sciences, Asmara, Eritrea
| | - Lidia Legese
- Epidemiology and Public Health, College of Health Sciences, Asmara, Eritrea
| | - Robel Afewerki
- Epidemiology and Public Health, College of Health Sciences, Asmara, Eritrea
| | | | | | - Ayubo Kampango
- Instituto Nacional de Saude, Maputo, Mozambique.,Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
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26
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Lautu-Gumal D, Razook Z, Koleala T, Nate E, McEwen S, Timbi D, Hetzel MW, Lavu E, Tefuarani N, Makita L, Kazura J, Mueller I, Pomat W, Laman M, Robinson LJ, Barry AE. Surveillance of molecular markers of Plasmodium falciparum artemisinin resistance (kelch13 mutations) in Papua New Guinea between 2016 and 2018. Int J Parasitol Drugs Drug Resist 2021; 16:188-193. [PMID: 34271323 PMCID: PMC8286961 DOI: 10.1016/j.ijpddr.2021.06.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/22/2021] [Accepted: 06/25/2021] [Indexed: 11/28/2022]
Abstract
Plasmodium falciparum resistance to artemisinin-based combination therapy (ACT) is a global threat to malaria control and elimination efforts. Mutations in the P. falciparum kelch13 gene (Pfk13) that are associated with delayed parasite clearance have emerged on the Thai-Cambodian border since 2008. There is growing evidence of widespread Pfk13 mutations throughout South-East Asia and they have independently emerged in other endemic regions. In Papua New Guinea (PNG), Pfk13 “C580Y” mutant parasites with reduced in vitro sensitivity to artemisinin have been isolated in Wewak, a port town in East Sepik Province. However, the extent of any local spread of these mutant parasites in other parts of PNG is unknown. We investigated the prevalence of Pfk13 mutations in multiple malaria-endemic regions of PNG. P. falciparum isolates (n = 1152) collected between 2016 and 2018 and assessed for Pfk13 variation by sequencing. Of 663 high quality Pfk13 sequences a total of five variants were identified. They included C580Y, a mutation at a previously documented polymorphic locus: N499K, and three previously undescribed mutations: R471C, K586E and Y635C. All variants were found in single isolates, indicating that these Pfk13 mutations were rare in the areas surveyed. Notably, C580Y was absent from Maprik district, which neighbours Wewak where C580Y mutant parasites were previously identified. The single C580Y isolate was found in the port town of Lae, Morobe Province, a potential entry site for the importation of drug resistant parasites into PNG. Although sample size in this location was small (n = 5), our identification of a C580Y mutant in this second location is concerning, highlighting the urgent need for further surveillance in Lae. Other Pfk13 mutants were rare in PNG between 2016 and 2018. Continued surveillance for molecular markers of drug resistance is critically important to inform malaria control in PNG.
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Affiliation(s)
- Dulcie Lautu-Gumal
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia; Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea; Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia.
| | - Zahra Razook
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; Institute for Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Tamarah Koleala
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Elma Nate
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Samuel McEwen
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia
| | - Diana Timbi
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Manuel W Hetzel
- Health Interventions Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Evelyn Lavu
- Papua New Guinea Central Public Health Laboratories, Port Moresby, National Capital District, Papua New Guinea
| | - Nakapi Tefuarani
- School of Medicine & Health Sciences, University of Papua New Guinea, Port Moresby, National Capital District, Papua New Guinea
| | - Leo Makita
- Papua New Guinea National Department of Health, Port Moresby, National Capital District, Papua New Guinea
| | - James Kazura
- Centre for Global Health Diseases, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia; Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - William Pomat
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Moses Laman
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Leanne J Robinson
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia; Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea; Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; School of Preventative Medicine and Public Health, Monash University, Melbourne, Victoria, Australia
| | - Alyssa E Barry
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia; Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; Institute for Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Geelong, Victoria, Australia
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Pons-Duran C, Llach M, Sacoor C, Sanz S, Macete E, Arikpo I, Ramírez M, Meremikwu M, Mbombo Ndombe D, Méndez S, Manun'Ebo MF, Ramananjato R, Rabeza VR, Tholandi M, Roman E, Pagnoni F, González R, Menéndez C. Coverage of intermittent preventive treatment of malaria in pregnancy in four sub-Saharan countries: findings from household surveys. Int J Epidemiol 2021; 50:550-559. [PMID: 33349871 PMCID: PMC8128463 DOI: 10.1093/ije/dyaa233] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/26/2020] [Indexed: 11/25/2022] Open
Abstract
Background Intermittent preventive treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) is a key malaria prevention strategy in areas with moderate to high transmission. As part of the TIPTOP (Transforming IPT for Optimal Pregnancy) project, baseline information about IPTp coverage was collected in eight districts from four sub-Saharan countries: Democratic Republic of Congo (DRC), Madagascar, Mozambique and Nigeria. Methods Cross-sectional household surveys were conducted using a multistage cluster sampling design to estimate the coverage of IPTp and antenatal care attendance. Eligible participants were women of reproductive age who had ended a pregnancy in the 12 months preceding the interview and who had resided in the selected household during at least the past 4 months of pregnancy. Coverage was calculated using percentages and 95% confidence intervals. Results A total of 3911 women were interviewed from March to October 2018. Coverage of at least three doses of IPTp (IPTp3+) was 22% and 24% in DRC project districts; 23% and 12% in Madagascar districts; 11% and 16% in Nigeria local government areas; and 63% and 34% in Mozambique districts. In DRC, Madagascar and Nigeria, more than two-thirds of women attending at least four antenatal care visits during pregnancy received less than three doses of IPTp. Conclusions The IPTp3+ uptake in the survey districts was far from the universal coverage. However, one of the study districts in Mozambique showed a much higher coverage of IPTp3+ than the other areas, which was also higher than the 2018 average national coverage of 41%. The reasons for the high IPTp3+ coverage in this Mozambican district are unclear and require further study.
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Affiliation(s)
- Clara Pons-Duran
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Spain
| | - Mireia Llach
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Spain
| | - Charfudin Sacoor
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Sergi Sanz
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Spain.,Departament de Fonaments Clínics, Facultat de Medicina, Universitat de Barcelona (UB), Barcelona, Spain
| | - Eusebio Macete
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Iwara Arikpo
- Cross River Health and Demographic Surveillance System, University of Calabar, Cross River State, Nigeria
| | - Máximo Ramírez
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Spain
| | - Martin Meremikwu
- Cross River Health and Demographic Surveillance System, University of Calabar, Cross River State, Nigeria
| | - Didier Mbombo Ndombe
- Bureau d'Étude et de Gestion de l'Information Statistique (BÉGIS), Kinshasa, DRC
| | - Susana Méndez
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Manu F Manun'Ebo
- Bureau d'Étude et de Gestion de l'Information Statistique (BÉGIS), Kinshasa, DRC
| | - Ranto Ramananjato
- Malagasy Associates for Numerical Information and Statistical Analysis (MANISA), Antananarivo, Madagascar
| | - Victor R Rabeza
- Malagasy Associates for Numerical Information and Statistical Analysis (MANISA), Antananarivo, Madagascar
| | - Maya Tholandi
- Jhpiego, Affiliate of Johns Hopkins University, Baltimore, MD, USA
| | - Elaine Roman
- Jhpiego, Affiliate of Johns Hopkins University, Baltimore, MD, USA
| | - Franco Pagnoni
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Raquel González
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Spain
| | - Clara Menéndez
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
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Sinzinkayo D, Baza D, Gnanguenon V, Koepfli C. The lead-up to epidemic transmission: malaria trends and control interventions in Burundi 2000 to 2019. Malar J 2021; 20:298. [PMID: 34215270 PMCID: PMC8249825 DOI: 10.1186/s12936-021-03830-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/23/2021] [Indexed: 11/10/2022] Open
Abstract
Burundi has experienced an increase in malaria cases since 2000, reaching 843,000 cases per million inhabitants in 2019, a more than twofold increase compared to the early 2000s. Burundi thus contrasts the decreasing number of cases in many other African countries. To evaluate the impact of malaria control on this increase, data on interventions from 2000 to 2019 were compiled. Over this period, the number of health facilities increased threefold, and the number of tests 20-fold. The test positivity rate remained stable at around 50-60% in most years. Artemisinin-based combination therapy was introduced in 2003, initially using artesunate-amodiaquine and changed to artemether-lumefantrine in 2019/2020. Mass distribution campaigns of insecticide-treated bed nets were conducted, and indoor residual spraying and intermittent preventive treatment in pregnancy introduced. Thus, the increase in cases was not the result of faltering control activities. Increased testing was likely a key contributor to higher case numbers. Despite the increase in testing, the test positivity rate remined high, indicating that current case numbers might still underestimate the true burden.
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Affiliation(s)
- Denis Sinzinkayo
- University of Burundi, Bujumbura, Burundi.,National Malaria Control Program, Ministry of Health, Bujumbura, Burundi
| | - Dismas Baza
- World Health Organization, Burundi Country Office, Bujumbura, Burundi
| | - Virgile Gnanguenon
- PMI VectorLink Project, U.S. Agency for International Development, Abt Associates, Bujumbura, Burundi
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Molina-de la Fuente I, Pastor A, Herrador Z, Benito A, Berzosa P. Impact of Plasmodium falciparum pfhrp2 and pfhrp3 gene deletions on malaria control worldwide: a systematic review and meta-analysis. Malar J 2021; 20:276. [PMID: 34158065 PMCID: PMC8220794 DOI: 10.1186/s12936-021-03812-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 06/11/2021] [Indexed: 12/15/2022] Open
Abstract
Background Deletion of pfhrp2 and/or pfhrp3 genes cause false negatives in malaria rapid diagnostic test (RDT) and threating malaria control strategies. This systematic review aims to assess the main methodological aspects in the study of pfhrp2 and pfhrp3 gene deletions and its global epidemiological status, with special focus on their distribution in Africa; and its possible impact in RDT. Methods The systematic review was conducted by examining the principal issues of study design and methodological workflow of studies addressing pfhrp2 deletion. Meta-analysis was applied to represent reported prevalences of pfhrp2 and pfhrp3 single and double deletion in the World Health Organization (WHO) region. Pooled-prevalence of deletions was calculated using DerSimonnian-Laird random effect model. Then, in-deep analysis focused on Africa was performed to assess possible variables related with these deletions. Finally, the impact of these deletions in RDT results was analysed combining reported information about RDT sensitivity and deletion prevalences. Results 49 articles were included for the systematic review and 37 for the meta-analysis, 13 of them placed in Africa. Study design differs significantly, especially in terms of population sample and information reported, resulting in high heterogeneity between studies that difficulties comparisons and merged conclusions. Reported prevalences vary widely in all the WHO regions, significantly higher deletion were reported in South-Central America, following by Africa and Asia. Pfhrp3 deletion is more prevalent (43% in South-Central America; 3% in Africa; and 1% in Asia) than pfhrp2 deletion (18% in South-Central America; 4% in Africa; and 3% in Asia) worldwide. In Africa, there were not found differences in deletion prevalence by geographical or population origin of samples. The prevalence of deletion among false negatives ranged from 0 to 100% in Africa, but in Asia and South-Central America was only up to 90% and 48%, respectively, showing substantial relation between deletions and false negatives. Conclusion The concerning prevalence of pfhrp2, pfhrp3 and pfhrp2/3 gene deletions, as its possible implications in malaria control, highlights the importance of regular and systematic surveillance of these deletions. This review has also outlined that a standardized methodology could play a key role to ensure comparability between studies to get global conclusions. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-03812-0.
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Affiliation(s)
- Irene Molina-de la Fuente
- Department of Biomedicine and Biotechnology, School of Pharmacy, University of Alcalá, Alcalá de Henares, Madrid, Spain. .,Malaria and Neglected Diseases Laboratory, National Centre of Tropical Medicine, Institute of Health Carlos III, 28029, Madrid, Spain. .,Public Health and Epidemiology Research Group, School of Medicine, University of Alcalá, 28871, Alcalá de Henares, Madrid, Spain.
| | - Andrea Pastor
- Public Health and Epidemiology Research Group, School of Medicine, University of Alcalá, 28871, Alcalá de Henares, Madrid, Spain
| | - Zaida Herrador
- National Centre of Epidemiology, Institute of Health Carlos III, 28029, Madrid, Spain.,Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
| | - Agustín Benito
- Malaria and Neglected Diseases Laboratory, National Centre of Tropical Medicine, Institute of Health Carlos III, 28029, Madrid, Spain.,Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
| | - Pedro Berzosa
- Malaria and Neglected Diseases Laboratory, National Centre of Tropical Medicine, Institute of Health Carlos III, 28029, Madrid, Spain.,Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
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Oboh MA, Oriero EC, Ndiaye T, Badiane AS, Ndiaye D, Amambua-Ngwa A. Comparative analysis of four malaria diagnostic tools and implications for malaria treatment in southwestern Nigeria. Int J Infect Dis 2021; 108:377-81. [PMID: 34044139 DOI: 10.1016/j.ijid.2021.05.049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 05/18/2021] [Accepted: 05/21/2021] [Indexed: 01/24/2023] Open
Abstract
OBJECTIVES One of the problems encountered in malaria control and elimination is inaccurate diagnosis, resulting from the degree of sensitivity of the different malaria diagnostic tools. Even though microscopy remains the gold standard for malaria diagnosis, more sensitive and robust diagnostic tools such as polymerase chain reactions (PCR) are used in research settings to monitor interventions and track sub-microscopic infections due to some of the drawbacks of microscopy. Since diagnosis is a critical determinant for rational malaria treatment, it is imperative that accurate diagnosis must be assured for an effective treatment plan. Therefore, this study compared two routinely used point of care malaria diagnostic tools with two molecular tools and discussed their implication for malaria treatment. DESIGN In this study, 436 individuals with suspected malaria were sampled and systematically tested using four methods, namely rapid diagnostic test (henceforth referred to as malaria RDT- mRDT), microscopy, nested PCR (nPCR), and quantitative PCR (qPCR). Test sensitivities and specificities were compared, and their level of concordance was determined. RESULTS With nPCR as the gold standard, a false positivity rate of 42.2%, 8.9%, and 57.8% was obtained for mRDT, microscopy, and qPCR. Similarly, false negativity rates of 12.5%, 62.5%, and 0.8% were obtained for each of the methods mentioned above, respectively. Of all the tools assessed, qPCR gave the highest sensitivity (99.2%) and moderate specificity (42.2%), followed by the mRDT kit used (87.5%). CONCLUSIONS With the detection of a high false positivity rate based on mRDT and a substantial proportion of sub-microscopic carriers in this study area by nested/quantitative PCR, we recommend that these molecular tools should be in specialized laboratories within the region to (i) track and treat sub-microscopic carriers to prevent their contribution to malaria transmission; (ii) provide reliable epidemiological data using high throughput testing tools for evaluating malaria interventions.
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Galindo MS, Lambert Y, Mutricy L, Garancher L, Bordalo Miller J, Gomes JH, Sanna A, Peterka C, Hilderal H, Cairo H, Hiwat H, Nacher M, Suárez-Mutis MC, Vreden S, Douine M. Setting-up a cross-border action-research project to control malaria in remote areas of the Amazon: describing the birth and milestones of a complex international project (Malakit). Malar J 2021; 20:216. [PMID: 33975624 PMCID: PMC8111981 DOI: 10.1186/s12936-021-03748-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 04/28/2021] [Indexed: 11/27/2022] Open
Abstract
Background In French Guiana, gold miners working illegally represents a major reservoir of malaria. This mobile population, mainly of Brazilian descent, enters the French Guianese forest from neighbouring countries, Suriname and Brazil. A complex and innovative intervention was piloted as a cooperation with the three involved countries involved to control malaria in this specific population. The principle was that health workers called “facilitators” provide the participants with a self-diagnosis and self-treatment kit along with adequate training and material to rapidly manage an episode of malaria symptoms on their own, when they find themselves isolated from health care services. Methods This paper describes the design, development, content of the intervention and players’ organization of this multi-country project, the opportunities and constraints encountered, and the lessons learnt at this stage. Results The choice not to implement the usual “Test and Treat” approach within the community is mainly driven by regulatory reasons. The content of medical messages tends to balance the tension between thoroughness, accuracy and efficacy. The wide range of tools developed through a participatory approach was intended to cope with the challenges of the literacy level of the target population. Despite the difficulties encountered due to language, regulation differences and distance between partners, cooperation was fruitful, due to the complementary of stakeholders, their involvement at all important stages and regular face-to-face meetings. Discussion and conclusion This experience shows the feasibility of an ambitious project of action-research in a border malaria context, involving several countries and with a mobile and undocumented population. It reveals some factors of success which may be transferable in analogous settings. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-03748-5.
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Affiliation(s)
- Muriel Suzanne Galindo
- Centre d'Investigation Clinique Antilles-Guyane, Inserm 1424, Centre Hospitalier de Cayenne Andrée Rosemon, Cayenne, French Guiana.
| | - Yann Lambert
- Centre d'Investigation Clinique Antilles-Guyane, Inserm 1424, Centre Hospitalier de Cayenne Andrée Rosemon, Cayenne, French Guiana
| | - Louise Mutricy
- Centre d'Investigation Clinique Antilles-Guyane, Inserm 1424, Centre Hospitalier de Cayenne Andrée Rosemon, Cayenne, French Guiana
| | | | | | | | - Alice Sanna
- Agence Régionale de Santé de la Guyane, Cayenne, French Guiana
| | - Cassio Peterka
- National Malaria Control Programme, Ministry of Health of Brazil, Brasilia, Brazil
| | - Hélène Hilderal
- Centre d'Investigation Clinique Antilles-Guyane, Inserm 1424, Centre Hospitalier de Cayenne Andrée Rosemon, Cayenne, French Guiana
| | - Hedley Cairo
- National Malaria Control Programme, Ministry of Health of Suriname, Paramaribo, Suriname
| | - Helene Hiwat
- National Malaria Control Programme, Ministry of Health of Suriname, Paramaribo, Suriname
| | - Mathieu Nacher
- Centre d'Investigation Clinique Antilles-Guyane, Inserm 1424, Centre Hospitalier de Cayenne Andrée Rosemon, Cayenne, French Guiana
| | | | - Stephen Vreden
- Foundation for the Advancement of Scientific Research in Suriname, Paramaribo, Suriname
| | - Maylis Douine
- Centre d'Investigation Clinique Antilles-Guyane, Inserm 1424, Centre Hospitalier de Cayenne Andrée Rosemon, Cayenne, French Guiana
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Manana PN, Jewett S, Zikhali J, Dlamini D, Mabaso N, Mlambo Z, Ngobese R, Munhenga G. "Maskandi experience": exploring the use of a cultural song for community engagement in preparation for a pilot Sterile Insect Technique release programme for malaria vector control in KwaZulu-Natal Province, South Africa 2019. Malar J 2021; 20:204. [PMID: 33910575 PMCID: PMC8082840 DOI: 10.1186/s12936-021-03736-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 04/16/2021] [Indexed: 11/12/2022] Open
Abstract
Background An assessment of the Sterile Insect Technique (SIT) as a complementary malaria vector control tool, is at an advanced stage in South Africa. The technique involves the release of laboratory-reared sterilized male mosquitoes of the major malaria vector Anopheles arabiensis, raising social, ethical and regulatory concerns. Therefore, its implementation largely depends on community participation and acceptance. Against this background, it is critical that robust and effective community strategies are developed. This study describes the development of a cultural song to engage the community and increase awareness on SIT and malaria control in KwaZulu-Natal, South Africa. Methods An exploratory concurrent mixed-methods study was conducted to get opinions about the effectiveness of a cultural song developed to engage communities and increase acceptability of the SIT technology. Two self-administered surveys (expert and community) were conducted. Additionally, more in depth opinions of the song and its effectiveness in conveying the intended information were investigated through three community dialogue sessions with community members in the study area. Results A total of 40 experts and 54 community members participated in the survey. Four themes were identified in relation to the appropriateness and effectiveness of the song, with a fifth theme focused on recommendations for adaptations. Overall, the song was well received with the audience finding it entertaining and informative. Responses to unstructured questions posed after the song showed an increase in the knowledge on malaria transmission and SIT technology. In particular, the explanation that male mosquitoes do not bite allayed anxiety and fears about the SIT technology. Conclusion The song was deemed both culturally appropriate and informative in engaging community members about the SIT technology. It proved useful in promoting health messages and conveying SIT technology as a complementary malaria vector control tool. With minor adaptations, the song has potential as an area-wide community engagement tool in areas targeted for sterile male releases. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-03736-9.
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Affiliation(s)
- Pinky N Manana
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases (NICD), Division of National Health Laboratory Services (NHLS), Johannesburg, South Africa. .,Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
| | - Sara Jewett
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Jabulani Zikhali
- Clinton Health Access Initiative, Malaria, KwaZulu-Natal, South Africa.,Department of Health, Environmental Health, Malaria and Communicable Disease Control, KwaZulu-Natal, South Africa
| | - Dumsani Dlamini
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Nondumiso Mabaso
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Zothile Mlambo
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Roxanne Ngobese
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Givemore Munhenga
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases (NICD), Division of National Health Laboratory Services (NHLS), Johannesburg, South Africa.,Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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Hartley S, Smith RDJ, Kokotovich A, Opesen C, Habtewold T, Ledingham K, Raymond B, Rwabukwali CB. Ugandan stakeholder hopes and concerns about gene drive mosquitoes for malaria control: new directions for gene drive risk governance. Malar J 2021; 20:149. [PMID: 33726763 PMCID: PMC7968178 DOI: 10.1186/s12936-021-03682-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 03/03/2021] [Indexed: 11/17/2022] Open
Abstract
Background The African Union’s High-Level Panel on Emerging Technologies identified gene drive mosquitoes as a priority technology for malaria elimination. The first field trials are expected in 5–10 years in Uganda, Mali or Burkina Faso. In preparation, regional and international actors are developing risk governance guidelines which will delineate the framework for identifying and evaluating risks. Scientists and bioethicists have called for African stakeholder involvement in these developments, arguing the knowledge and perspectives of those people living in malaria-afflicted countries is currently missing. However, few African stakeholders have been involved to date, leaving a knowledge gap about the local social-cultural as well as ecological context in which gene drive mosquitoes will be tested and deployed. This study investigates and analyses Ugandan stakeholders’ hopes and concerns about gene drive mosquitoes for malaria control and explores the new directions needed for risk governance. Methods This qualitative study draws on 19 in-depth semi-structured interviews with Ugandan stakeholders in 2019. It explores their hopes for the technology and the risks they believed pertinent. Coding began at a workshop and continued through thematic analysis. Results Participants’ hopes and concerns for gene drive mosquitoes to address malaria fell into three themes: (1) ability of gene drive mosquitoes to prevent malaria infection; (2) impacts of gene drive testing and deployment; and, (3) governance. Stakeholder hopes fell almost exclusively into the first theme while concerns were spread across all three. The study demonstrates that local stakeholders are able and willing to contribute relevant and important knowledge to the development of risk frameworks. Conclusions International processes can provide high-level guidelines, but risk decision-making must be grounded in the local context if it is to be robust, meaningful and legitimate. Decisions about whether or not to release gene drive mosquitoes as part of a malaria control programme will need to consider the assessment of both the risks and the benefits of gene drive mosquitoes within a particular social, political, ecological, and technological context. Just as with risks, benefits—and importantly, the conditions that are necessary to realize them—must be identified and debated in Uganda and its neighbouring countries.
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Affiliation(s)
- Sarah Hartley
- University of Exeter, Northcote House, Queen's Drive, Exeter, EX4 4QJ, UK.
| | - Robert D J Smith
- Science, Technology & Innovation Studies, School of Social and Political Sciences, University of Edinburgh, Chisholm House, High School Yard, Edinburgh, EH1 1LZ, UK
| | - Adam Kokotovich
- Department of Forestry & Environmental Resources, Genetic Engineering and Society Center, North Carolina State University, Campus Box 7565, Raleigh, NC, 27695-7565, USA
| | - Chris Opesen
- Makerere University, PO Box 7062, Kampala, Uganda
| | - Tibebu Habtewold
- Department of Life Sciences, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Katie Ledingham
- University of Exeter, Northcote House, Queen's Drive, Exeter, EX4 4QJ, UK
| | - Ben Raymond
- University of Exeter, Penryn Campus, Treliever Road, Penryn, TR10 9FE, UK
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Mawejje HD, Kilama M, Kigozi SP, Musiime AK, Kamya M, Lines J, Lindsay SW, Smith D, Dorsey G, Donnelly MJ, Staedke SG. Impact of seasonality and malaria control interventions on Anopheles density and species composition from three areas of Uganda with differing malaria endemicity. Malar J 2021; 20:138. [PMID: 33678166 PMCID: PMC7938603 DOI: 10.1186/s12936-021-03675-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 02/25/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are the malaria control interventions primarily responsible for reductions in transmission intensity across sub-Saharan Africa. These interventions, however, may have differential impact on Anopheles species composition and density. This study examined the changing pattern of Anopheles species in three areas of Uganda with markedly different transmission intensities and different levels of vector control. METHODS From October 2011 to June 2016 mosquitoes were collected monthly using CDC light traps from 100 randomly selected households in three areas: Walukuba (low transmission), Kihihi (moderate transmission) and Nagongera (high transmission). LLINs were distributed in November 2013 in Walukuba and Nagongera and in June 2014 in Kihihi. IRS was implemented only in Nagongera, with three rounds of bendiocarb delivered between December 2014 and June 2015. Mosquito species were identified morphologically and by PCR (Polymerase Chain Reaction). RESULTS In Walukuba, LLIN distribution was associated with a decline in Anopheles funestus vector density (0.07 vs 0.02 mosquitoes per house per night, density ratio [DR] 0.34, 95% CI: 0.18-0.65, p = 0.001), but not Anopheles gambiae sensu stricto (s.s.) nor Anopheles arabiensis. In Kihihi, over 98% of mosquitoes were An. gambiae s.s. and LLIN distribution was associated with a decline in An. gambiae s.s. vector density (4.00 vs 2.46, DR 0.68, 95% CI: 0.49-0.94, p = 0.02). In Nagongera, the combination of LLINs and multiple rounds of IRS was associated with almost complete elimination of An. gambiae s.s. (28.0 vs 0.17, DR 0.004, 95% CI: 0.002-0.009, p < 0.001), and An. funestus sensu lato (s.l.) (3.90 vs 0.006, DR 0.001, 95% CI: 0.0005-0.004, p < 0.001), with a less pronounced decline in An. arabiensis (9.18 vs 2.00, DR 0.15 95% CI: 0.07-0.33, p < 0.001). CONCLUSIONS LLIN distribution was associated with reductions in An. funestus s.l. in the lowest transmission site and An. gambiae s.s. in the moderate transmission site. In the highest transmission site, a combination of LLINs and multiple rounds of IRS was associated with the near collapse of An. gambiae s.s. and An. funestus s.l. Following IRS, An. arabiensis, a behaviourally resilient vector, became the predominant species, which may have implications for malaria vector control activities. Development of interventions targeted at outdoor biting remains a priority.
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Affiliation(s)
- Henry Ddumba Mawejje
- Infectious Diseases Research Collaboration, Kampala, Uganda. .,London School of Hygiene and Tropical Medicine, London, UK.
| | - Maxwell Kilama
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Simon P Kigozi
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Alex K Musiime
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Moses Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda.,Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Jo Lines
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - David Smith
- Department of Health Metrics Sciences, University of Washington, Seattle, WA, USA
| | - Grant Dorsey
- Department of Medicine, University of California, San Francisco, USA
| | - Martin J Donnelly
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place Liverpool, UK
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Ahmad RA, Ferdiana A, Surendra H, Sy TR, Herbianto D, Rahayujati TB, Rejeki DSS, Murhandarwati EEH. A participatory approach to address within-country cross-border malaria: the case of Menoreh Hills in Java, Indonesia. Malar J 2021; 20:137. [PMID: 33676491 PMCID: PMC7937247 DOI: 10.1186/s12936-021-03673-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 02/25/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria remains a significant public health issue in Indonesia. Most of the endemic areas are in the eastern parts of Indonesia, but there are a few remaining foci of persistent endemic malaria in Java, particularly in Menoreh Hills, a region bordering three districts of two provinces on this island. Despite a commitment to build a partnership to eliminate cross-border malaria, there is a lack of understanding of how this partnership might be translated into an implementable strategic plan. The study aims to provide evidence of how a participatory approach was used to strengthen the cross-border collaboration and stakeholders' capacity to develop a joint strategic, operational, and costing plan for cross-border malaria elimination. METHODS A participatory action research was conducted from January to August 2017, involving participants from the village, district, provincial, and national levels. This study was conducted in seven phases, including document review, focus group discussions (FGDs), planning and costing workshops, and a dissemination meeting. A total of 44 participants from primary health centres (PHC) and 27 representatives of affected villages in three districts, 16 participants from the district and provincial malaria programmes and planning bureaus, and 11 participants from the national level were involved in the processes. Data on priority issues, costing, programme coverage, and administration were collected. Thematic coding and feedback were used for analysis. RESULTS Problems identified by stakeholders included low community awareness and participation in malaria prevention, high mobility across three districts, lack of financial and human resources, lack of inter-district coordination, and poor implementation of migration surveillance. Cross-border strategies identified to address malaria were improving cross-border migration surveillance, strengthening the network, governance, and advocacy of malaria control implementation across borders, and developing the malaria information system. A working group composed of the three districts' representatives authorized to decide on cross-border issues will be created. CONCLUSIONS The participatory approach was applicable in cross-border malaria planning for within-country settings and useful in enhancing stakeholders' capacities as implementers. While done in a participatory way, the joint plan crafted was a non-binding agreement; stakeholders should advocate to ensure adequate funds are poured into mobilizing the programme.
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Affiliation(s)
- Riris Andono Ahmad
- Centre for Tropical Medicine, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia. .,Department of Biostatistics, Epidemiology and Population Health, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia.
| | - Astri Ferdiana
- Centre for Tropical Medicine, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia.,Department of Public Health, Faculty of Medicine, University of Mataram, Mataram, Indonesia
| | - Henry Surendra
- Centre for Tropical Medicine, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia.,Eijkman-Oxford Clinical Research Unit, Jakarta, Indonesia
| | - Tyrone Reden Sy
- Centre for Tropical Medicine, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Deni Herbianto
- Centre for Tropical Medicine, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Theodola Baning Rahayujati
- Disease Prevention and Control, District Health Office of Kulon Progo, Kulon Progo, Yogyakarta, Indonesia
| | - Dwi Sarwani Sri Rejeki
- Department of Public Health, Faculty of Health Sciences, Universitas Jenderal Soedirman, Purwokerto, Central Java, Indonesia
| | - E Elsa Herdiana Murhandarwati
- Centre for Tropical Medicine, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia.,Department of Parasitology, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia
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Mapua SA, Finda MF, Nambunga IH, Msugupakulya BJ, Ukio K, Chaki PP, Tripet F, Kelly AH, Christofides N, Lezaun J, Okumu FO. Addressing key gaps in implementation of mosquito larviciding to accelerate malaria vector control in southern Tanzania: results of a stakeholder engagement process in local district councils. Malar J 2021; 20:123. [PMID: 33653355 PMCID: PMC7923449 DOI: 10.1186/s12936-021-03661-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 02/20/2021] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Larval source management was historically one of the most effective malaria control methods but is now widely deprioritized in Africa, where insecticide-treated nets (ITNs) and indoor residual spraying (IRS) are preferred. However, in Tanzania, following initial successes in urban Dar-es-Salaam starting early-2000s, the government now encourages larviciding in both rural and urban councils nationwide to complement other efforts; and a biolarvicide production-plant has been established outside the commercial capital. This study investigated key obstacles and opportunities relevant to effective rollout of larviciding for malaria control, with a focus on the meso-endemic region of Morogoro, southern Tanzania. METHODS Key-informants were interviewed to assess awareness and perceptions regarding larviciding among designated health officials (malaria focal persons, vector surveillance officers and ward health officers) in nine administrative councils (n = 27). Interviewer-administered questionnaires were used to assess awareness and perceptions of community members in selected areas regarding larviciding (n = 490). Thematic content analysis was done and descriptive statistics used to summarize the findings. RESULTS A majority of malaria control officials had participated in larviciding at least once over the previous three years. A majority of community members had neutral perceptions towards positive aspects of larviciding, but overall support for larviciding was high, although several challenges were expressed, notably: (i) insufficient knowledge for identifying relevant aquatic habitats of malaria vectors and applying larvicides, (ii) inadequate monitoring of programme effectiveness, (iii) limited financing, and (iv) lack of personal protective equipment. Although the key-informants reported sensitizing local communities, most community members were still unaware of larviciding and its potential. CONCLUSIONS The larviciding programme was widely supported by both communities and malaria control officials, but there were gaps in technical knowledge, implementation and public engagement. To improve overall impact, it is important to: (i) intensify training efforts, particularly for identifying habitats of important vectors, (ii) adopt standard technical principles for applying larvicides or larval source management, (iii) improve financing for local implementation and (iv) improve public engagement to boost community awareness and participation. These lessons could also be valuable for other malaria endemic areas wishing to deploy larviciding for malaria control or elimination.
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Affiliation(s)
- Salum A Mapua
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Morogoro, Tanzania.
| | - Marceline F Finda
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Morogoro, Tanzania
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Ismail H Nambunga
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Morogoro, Tanzania
| | - Betwel J Msugupakulya
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Morogoro, Tanzania
- School of Life Science and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania
| | - Kusirye Ukio
- President's Office-Regional Administration and Local Government, Morogoro Regional Secretariat, P.O. Box 610, Morogoro, Tanzania
| | - Prosper P Chaki
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Morogoro, Tanzania
| | - Frederic Tripet
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Huxley Building, Keele, Staffordshire, ST5 5BG, UK
| | - Ann H Kelly
- Department of Global Health and Social Medicine, King's College London, London, UK
| | - Nicola Christofides
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Javier Lezaun
- Institute for Science, Innovation and Society, School of Anthropology and Museum Ethnography, University of Oxford, 64 Banbury Road, Oxford, OX2 6PN, UK
| | - Fredros O Okumu
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Morogoro, Tanzania.
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
- School of Life Science and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania.
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK.
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Chakraborty M, Ramaiah A, Adolfi A, Halas P, Kaduskar B, Ngo LT, Jayaprasad S, Paul K, Whadgar S, Srinivasan S, Subramani S, Bier E, James AA, Emerson JJ. Hidden genomic features of an invasive malaria vector, Anopheles stephensi, revealed by a chromosome-level genome assembly. BMC Biol 2021; 19:28. [PMID: 33568145 PMCID: PMC7876825 DOI: 10.1186/s12915-021-00963-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 01/19/2021] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND The mosquito Anopheles stephensi is a vector of urban malaria in Asia that recently invaded Africa. Studying the genetic basis of vectorial capacity and engineering genetic interventions are both impeded by limitations of a vector's genome assembly. The existing assemblies of An. stephensi are draft-quality and contain thousands of sequence gaps, potentially missing genetic elements important for its biology and evolution. RESULTS To access previously intractable genomic regions, we generated a reference-grade genome assembly and full transcript annotations that achieve a new standard for reference genomes of disease vectors. Here, we report novel species-specific transposable element (TE) families and insertions in functional genetic elements, demonstrating the widespread role of TEs in genome evolution and phenotypic variation. We discovered 29 previously hidden members of insecticide resistance genes, uncovering new candidate genetic elements for the widespread insecticide resistance observed in An. stephensi. We identified 2.4 Mb of the Y chromosome and seven new male-linked gene candidates, representing the most extensive coverage of the Y chromosome in any mosquito. By tracking full-length mRNA for > 15 days following blood feeding, we discover distinct roles of previously uncharacterized genes in blood metabolism and female reproduction. The Y-linked heterochromatin landscape reveals extensive accumulation of long-terminal repeat retrotransposons throughout the evolution and degeneration of this chromosome. Finally, we identify a novel Y-linked putative transcription factor that is expressed constitutively throughout male development and adulthood, suggesting an important role. CONCLUSION Collectively, these results and resources underscore the significance of previously hidden genomic elements in the biology of malaria mosquitoes and will accelerate the development of genetic control strategies of malaria transmission.
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Affiliation(s)
- Mahul Chakraborty
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, 92697, USA
| | - Arunachalam Ramaiah
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, 92697, USA
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, 92093-0335, USA
- Tata Institute for Genetics and Society, Center at inStem, Bangalore, Karnataka, 560065, India
| | - Adriana Adolfi
- Department of Microbiology & Molecular Genetics, University of California, Irvine, CA, 92697, USA
| | - Paige Halas
- Department of Microbiology & Molecular Genetics, University of California, Irvine, CA, 92697, USA
| | - Bhagyashree Kaduskar
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, 92093-0335, USA
- Tata Institute for Genetics and Society, Center at inStem, Bangalore, Karnataka, 560065, India
| | - Luna Thanh Ngo
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, 92697, USA
| | - Suvratha Jayaprasad
- Institute of Bioinformatics and Applied Biotechnology, Bangalore, KA, 560100, India
| | - Kiran Paul
- Institute of Bioinformatics and Applied Biotechnology, Bangalore, KA, 560100, India
| | - Saurabh Whadgar
- Institute of Bioinformatics and Applied Biotechnology, Bangalore, KA, 560100, India
| | - Subhashini Srinivasan
- Tata Institute for Genetics and Society, Center at inStem, Bangalore, Karnataka, 560065, India
- Institute of Bioinformatics and Applied Biotechnology, Bangalore, KA, 560100, India
| | - Suresh Subramani
- Tata Institute for Genetics and Society, Center at inStem, Bangalore, Karnataka, 560065, India
- Section of Molecular Biology, University of California, San Diego, La Jolla, CA, 92093-0322, USA
- Tata Institute for Genetics and Society, University of California, San Diego, La Jolla, CA, 92093-0335, USA
| | - Ethan Bier
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, 92093-0335, USA
- Tata Institute for Genetics and Society, University of California, San Diego, La Jolla, CA, 92093-0335, USA
| | - Anthony A James
- Department of Microbiology & Molecular Genetics, University of California, Irvine, CA, 92697, USA
- Tata Institute for Genetics and Society, University of California, San Diego, La Jolla, CA, 92093-0335, USA
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, 92697, USA
| | - J J Emerson
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, 92697, USA.
- Center for Complex Biological Systems, University of California, Irvine, CA, 92697, USA.
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Perera R, Caldera A, Wickremasinghe AR. Reactive Case Detection (RACD) and foci investigation strategies in malaria control and elimination: a review. Malar J 2020; 19:401. [PMID: 33172462 PMCID: PMC7653886 DOI: 10.1186/s12936-020-03478-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 11/02/2020] [Indexed: 11/30/2022] Open
Abstract
Background Reactive case detection (RACD) and foci investigation are key strategies in malaria elimination and prevention of its re-establishment. They are a key part of surveillance that has been recommended by the World Health Organization (WHO) to be considered as a core intervention and as one of the three pillars of the Global Technical Strategy for Malaria 2016–2030. Methods A search using the key words “Reactive Case Detection”, “RACD”, “RCD” and “Malaria” was carried out in PubMed, Scopus, Taylor and Francis online databases for studies published until 31st July 2019. The inclusion criteria for selection of articles for review included (1) how RACD is implemented in each country; (2) challenges faced in RACD implementation; (3) suggestions on how the effectiveness of RACD process can be improved. Results 411 titles were identified, 41 full text articles were screened and 29 were found eligible for inclusion in the review. Published literature on RACD, and case and foci investigations has mostly assessed the process of the activity. Most studies have documented that the yield of positives in RACD has been highest in the index case’s household and the immediate neighbourhood of the index case. Microscopy and RDTs are the common tests used in RACD. The guidelines for case and foci investigation, and RACD and PACD, are not universally adopted and are country-specific. Some of the limitations and challenges identified include lack of proper guidelines, logistic issues and problems with public compliance. Conclusions Although there is no documented evidence that RACD is useful in malaria elimination settings, most authors have opined that RACD is necessary for malaria elimination. Lack of knowledge in the target populations, a target radius and how to carry out the RACD process is a major challenge in the decision-making process.
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Affiliation(s)
- Ruwanthi Perera
- Department of Public Health, Faculty of Medicine, University of Kelaniya, P. O. Box 6, Thalagolla Road, Ragama, 11010, Sri Lanka
| | - Amandhi Caldera
- Department of Public Health, Faculty of Medicine, University of Kelaniya, P. O. Box 6, Thalagolla Road, Ragama, 11010, Sri Lanka
| | - A Rajitha Wickremasinghe
- Department of Public Health, Faculty of Medicine, University of Kelaniya, P. O. Box 6, Thalagolla Road, Ragama, 11010, Sri Lanka.
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Abstract
Malaria risk and endemicity is often associated with the nature of human habitation and living environment. The disappearance of malaria from regions where it had been endemic for centuries, such as coastal areas of southern England, has been attributed, at least in part, to improvement in the quality of housing. Moreover, indigenous malaria transmission ceased throughout England without the necessity to eliminate the vector mosquitoes. The principles of malaria transmission, as formulated following the thinking of the pioneers of malaria epidemiology, Ronald Ross and George Macdonald, show how this may happen. Malaria ceases to be sustainable where its reproduction number, R0, the number of new cases generated on average for each existing case of malaria, falls below 1. In the terms of a Ross/Macdonald analysis the reduced contact between humans and blood-feeding mosquitoes that is achieved through housing that is secure against mosquito entry can have a powerful effect in reducing malaria R0. The island of Sri Lanka, where malaria had been endemic probably for centuries previously, has reported no indigenous cases of malaria since 2012. The disappearance of malaria from Sri Lanka followed an effective attack upon malaria transmission by the Sri Lanka Anti Malaria Campaign. The targeted and enhanced efforts of this campaign launched in 1999, drove the malaria R0 below 1 for most of the period up to 2012, leading to a nearly continuous decline in malaria cases until their extinction. The decades leading up to the launch of these efforts were ones of general improvement of living environment and notably in the quality of housing stock. Studies in the late 1980s had shown that quality of housing in a highly malarious district of Sri Lanka was a strong determinant of malaria risk. Through its effects on malaria R0, improved housing is likely to have facilitated the malaria control and cessation of indigenous malaria transmission in Sri Lanka and that it will help reduce the risk of the re-introduction of malaria to the island.
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Affiliation(s)
- Richard Carter
- School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Nadira D Karunaweera
- Department of Parasitology, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka.
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Galactionova K, Velarde M, Silumbe K, Miller J, McDonnell A, Aguas R, Smith TA, Penny MA. Costing malaria interventions from pilots to elimination programmes. Malar J 2020; 19:332. [PMID: 32928227 PMCID: PMC7491157 DOI: 10.1186/s12936-020-03405-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 09/04/2020] [Indexed: 11/23/2022] Open
Abstract
Background Malaria programmes in countries with low transmission levels require evidence to optimize deployment of current and new tools to reach elimination with limited resources. Recent pilots of elimination strategies in Ethiopia, Senegal, and Zambia produced evidence of their epidemiological impacts and costs. There is a need to generalize these findings to different epidemiological and health systems contexts. Methods Drawing on experience of implementing partners, operational documents and costing studies from these pilots, reference scenarios were defined for rapid reporting (RR), reactive case detection (RACD), mass drug administration (MDA), and in-door residual spraying (IRS). These generalized interventions from their trial implementation to one typical of programmatic delivery. In doing so, resource use due to interventions was isolated from research activities and was related to the pilot setting. Costing models developed around this reference implementation, standardized the scope of resources costed, the valuation of resource use, and the setting in which interventions were evaluated. Sensitivity analyses were used to inform generalizability of the estimates and model assumptions. Results Populated with local prices and resource use from the pilots, the models yielded an average annual economic cost per capita of $0.18 for RR, $0.75 for RACD, $4.28 for MDA (two rounds), and $1.79 for IRS (one round, 50% households). Intervention design and resource use at service delivery were key drivers of variation in costs of RR, MDA, and RACD. Scale was the most important parameter for IRS. Overall price level was a minor contributor, except for MDA where drugs accounted for 70% of the cost. The analyses showed that at implementation scales comparable to health facility catchment area, systematic correlations between model inputs characterizing implementation and setting produce large gradients in costs. Conclusions Prospective costing models are powerful tools to explore resource and cost implications of policy alternatives. By formalizing translation of operational data into an estimate of intervention cost, these models provide the methodological infrastructure to strengthen capacity gap for economic evaluation in endemic countries. The value of this approach for decision-making is enhanced when primary cost data collection is designed to enable analysis of the efficiency of operational inputs in relation to features of the trial or the setting, thus facilitating transferability.
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Affiliation(s)
- Katya Galactionova
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | - Mar Velarde
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Kafula Silumbe
- Malaria Control and Elimination Partnership in Africa at PATH (MACEPA), Lusaka, Zambia
| | - John Miller
- Malaria Control and Elimination Partnership in Africa at PATH (MACEPA), Lusaka, Zambia
| | - Anthony McDonnell
- 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
| | - Ricardo Aguas
- 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
| | - Thomas A Smith
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Melissa A Penny
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
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Kattenberg JH, Gumal DL, Ome-Kaius M, Kiniboro B, Philip M, Jally S, Kasian B, Sambale N, Siba PM, Karl S, Barry AE, Felger I, Kazura JW, Mueller I, Robinson LJ. The epidemiology of Plasmodium falciparum and Plasmodium vivax in East Sepik Province, Papua New Guinea, pre- and post-implementation of national malaria control efforts. Malar J 2020; 19:198. [PMID: 32503607 PMCID: PMC7275396 DOI: 10.1186/s12936-020-03265-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 05/20/2020] [Indexed: 02/07/2023] Open
Abstract
Background In the past decade, national malaria control efforts in Papua New Guinea (PNG) have received renewed support, facilitating nationwide distribution of free long-lasting insecticidal nets (LLINs), as well as improvements in access to parasite-confirmed diagnosis and effective artemisinin-combination therapy in 2011–2012. Methods To study the effects of these intensified control efforts on the epidemiology and transmission of Plasmodium falciparum and Plasmodium vivax infections and investigate risk factors at the individual and household level, two cross-sectional surveys were conducted in the East Sepik Province of PNG; one in 2005, before the scale-up of national campaigns and one in late 2012-early 2013, after 2 rounds of LLIN distribution (2008 and 2011–2012). Differences between studies were investigated using Chi square (χ2), Fischer’s exact tests and Student’s t-test. Multivariable logistic regression models were built to investigate factors associated with infection at the individual and household level. Results The prevalence of P. falciparum and P. vivax in surveyed communities decreased from 55% (2005) to 9% (2013) and 36% to 6%, respectively. The mean multiplicity of infection (MOI) decreased from 1.8 to 1.6 for P. falciparum (p = 0.08) and from 2.2 to 1.4 for P. vivax (p < 0.001). Alongside these reductions, a shift towards a more uniform distribution of infections and illness across age groups was observed but there was greater heterogeneity across the study area and within the study villages. Microscopy positive infections and clinical cases in the household were associated with high rate infection households (> 50% of household members with Plasmodium infection). Conclusion After the scale-up of malaria control interventions in PNG between 2008 and 2012, there was a substantial reduction in P. falciparum and P. vivax infection rates in the studies villages in East Sepik Province. Understanding the extent of local heterogeneity in malaria transmission and the driving factors is critical to identify and implement targeted control strategies to ensure the ongoing success of malaria control in PNG and inform the development of tools required to achieve elimination. In household-based interventions, diagnostics with a sensitivity similar to (expert) microscopy could be used to identify and target high rate households.
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Affiliation(s)
- Johanna H Kattenberg
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea.,Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia.,Department of Biomedical Sciences, Institute of Tropical Medicine, Malariology Unit, Nationalestraat 155, 2000, Antwerp, Belgium
| | - Dulcie L Gumal
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea.,Disease Elimination Program, Vector-borne Diseases and Tropical Public Health Group, Burnet Institute, 85 Commercial Rd, Melbourne, VIC, 3004, Australia
| | - Maria Ome-Kaius
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea.,Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia
| | - Benson Kiniboro
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Matthew Philip
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Shadrach Jally
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Bernadine Kasian
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Naomi Sambale
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Peter M Siba
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea
| | - Stephan Karl
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea.,Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia
| | - Alyssa E Barry
- Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3010, Australia.,School of Medicine, Deakin University, Geelong and Burnet Institute, Melbourne, VIC, Australia
| | - Ingrid Felger
- Medical Parasitology and Infection Biology, Swiss Tropical & Public Health Institute, Socinstrasse 57, 4051, Basel, Switzerland
| | - James W Kazura
- Center for Global Health and Diseases, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH, 44106, USA
| | - Ivo Mueller
- Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3010, Australia.,Department of Parasites and Insect Vectors, Malaria Parasites and Hosts Unit, Pasteur Institute, 25-28 rue du Docteur-Roux, 75724, Paris Cedex 15, France
| | - Leanne J Robinson
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, PO Box 378, Madang, 511, MP, Papua New Guinea. .,Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC, 3052, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, 3010, Australia. .,Disease Elimination Program, Vector-borne Diseases and Tropical Public Health Group, Burnet Institute, 85 Commercial Rd, Melbourne, VIC, 3004, Australia.
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Finda MF, Christofides N, Lezaun J, Tarimo B, Chaki P, Kelly AH, Kapologwe N, Kazyoba P, Emidi B, Okumu FO. Opinions of key stakeholders on alternative interventions for malaria control and elimination in Tanzania. Malar J 2020; 19:164. [PMID: 32321534 PMCID: PMC7178586 DOI: 10.1186/s12936-020-03239-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 04/16/2020] [Indexed: 03/03/2023] Open
Abstract
Background Malaria control in Tanzania currently relies primarily on long-lasting insecticidal nets and indoor residual spraying, alongside effective case management and behaviour change communication. This study explored opinions of key stakeholders on the national progress towards malaria elimination, the potential of currently available vector control interventions in helping achieve elimination by 2030, and the need for alternative interventions that could be used to supplement malaria elimination efforts in Tanzania. Methods In this exploratory qualitative study, Focus group discussions were held with policy-makers, regulators, research scientists and community members. Malaria control interventions discussed were: (a) improved housing, (b) larval source management, (c) mass drug administration (MDA) with ivermectin to reduce vector densities, (d) release of modified mosquitoes, including genetically modified or irradiated mosquitoes, (e) targeted spraying of mosquito swarms, and (f) spatial repellents. Results Larval source management and spatial repellents were widely supported across all stakeholder groups, while insecticide-spraying of mosquito swarms was the least preferred. Support for MDA with ivermectin was high among policy makers, regulators and research scientists, but encountered opposition among community members, who instead expressed strong support for programmes to improve housing for poor people in high transmission areas. Policy makers, however, challenged the idea of government-supported housing improvement due to its perceived high costs. Techniques of mosquito modification, specifically those involving gene drives, were viewed positively by community members, policy makers and regulators, but encountered a high degree of scepticism among scientists. Overall, policy-makers, regulators and community members trusted scientists to provide appropriate advice for decision-making. Conclusion Stakeholder opinions regarding alternative malaria interventions were divergent except for larval source management and spatial repellents, for which there was universal support. MDA with ivermectin, housing improvement and modified mosquitoes were also widely supported, though each faced concerns from at least one stakeholder group. While policy-makers, regulators and community members all noted their reliance on scientists to make informed decisions, their reasoning on the benefits and disadvantages of specific interventions included factors beyond technical efficiency. This study suggests the need to encourage and strengthen dialogue between research scientists, policy makers, regulators and communities regarding new interventions.
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Affiliation(s)
- Marceline F Finda
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania. .,School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 1 Smuts Avenue, Braamfontein, 2000, South Africa.
| | - Nicola Christofides
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 1 Smuts Avenue, Braamfontein, 2000, South Africa
| | - Javier Lezaun
- Institute for Science, Innovation and Society, School of Anthropology and Museum Ethnography, University of Oxford, Oxford, UK
| | - Brian Tarimo
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania
| | - Prosper Chaki
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania
| | - Ann H Kelly
- Department of Global Health and Social Medicine, King's College, London, UK
| | - Ntuli Kapologwe
- President's Office, Regional Administration and Local Government, P. O Box 1923, Dodoma, Tanzania
| | - Paul Kazyoba
- National Institute for Medical Research, 3 Barack Obama Drive, Dar es Salaam, Tanzania
| | - Basiliana Emidi
- National Institute for Medical Research, 3 Barack Obama Drive, Dar es Salaam, Tanzania.,National Malaria Control Programme, P. O. Box 743, Dodoma, Tanzania
| | - Fredros O Okumu
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania.,School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 1 Smuts Avenue, Braamfontein, 2000, South Africa.,Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK.,School of Life Science and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania
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Tangena JAA, Hendriks CMJ, Devine M, Tammaro M, Trett AE, Williams I, DePina AJ, Sisay A, Herizo R, Kafy HT, Chizema E, Were A, Rozier J, Coleman M, Moyes CL. Indoor residual spraying for malaria control in sub-Saharan Africa 1997 to 2017: an adjusted retrospective analysis. Malar J 2020; 19:150. [PMID: 32276585 PMCID: PMC7149868 DOI: 10.1186/s12936-020-03216-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 03/30/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Indoor residual spraying (IRS) is a key tool for controlling and eliminating malaria by targeting vectors. To support the development of effective intervention strategies it is important to understand the impact of vector control tools on malaria incidence and on the spread of insecticide resistance. In 2006, the World Health Organization (WHO) stated that countries should report on coverage and impact of IRS, yet IRS coverage data are still sparse and unspecific. Here, the subnational coverage of IRS across sub-Saharan Africa for the four main insecticide classes from 1997 to 2017 were estimated. METHODS Data on IRS deployment were collated from a variety of sources, including the President's Malaria Initiative spray reports and National Malaria Control Programme reports, for all 46 malaria-endemic countries in sub-Saharan Africa from 1997 to 2017. The data were mapped to the applicable administrative divisions and the proportion of households sprayed for each of the four main insecticide classes; carbamates, organochlorines, organophosphates and pyrethroids was calculated. RESULTS The number of countries implementing IRS increased considerably over time, although the focal nature of deployment means the number of people protected remains low. From 1997 to 2010, DDT and pyrethroids were commonly used, then partly replaced by carbamates from 2011 and by organophosphates from 2013. IRS deployment since the publication of resistance management guidelines has typically avoided overlap between pyrethroid IRS and ITN use. However, annual rotations of insecticide classes with differing modes of action are not routinely used. CONCLUSION This study highlights the gaps between policy and practice, emphasizing the continuing potential of IRS to drive resistance. The data presented here can improve studies on the impact of IRS on malaria incidence and help to guide future malaria control efforts.
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Affiliation(s)
- Julie-Anne A Tangena
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK.
| | - Chantal M J Hendriks
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, OX3 7LF, UK
| | - Maria Devine
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, OX3 7LF, UK
| | - Meghan Tammaro
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, 6130 Executive Blvd, Rockville, MD, 20852, USA
| | - Anna E Trett
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Ignatius Williams
- Monitoring, & Evaluation Department, AngloGold Ashanti Malaria Limited, AO0540595 Obuasi Mine Road, P. O. Box 10, Obuasi, Ghana
| | - Adilson José DePina
- Malaria Pre-Elimination Program, CCS-SIDA/MSSS, Avenida Cidade Lisboa, "Prédio Bô Casa" 1º Andar, CP, 855, Praia, Cabo Verde
- Ecole Doctorale Des Sciences de La Vie, de la Santé et de l´Environnement (ED‑SEV), Université Cheikh Anta Diop (UCAD) de Dakar, BP 1386, Dakar, Sénégal
| | | | - Ramandimbiarijaona Herizo
- Programme national de lutte contre le paludisme, Androhibe en face ENAM, BP 101, Antananarivo, Madagascar
| | - Hmooda Toto Kafy
- Integrated Vector Management Department, Federal Ministry of Health, Khartoum, Sudan
| | - Elizabeth Chizema
- National Malaria Elimination Centre, Chainama Hills Hospital Grounds, Lusaka, Zambia
| | - Allan Were
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, 6130 Executive Blvd, Rockville, MD, 20852, USA
| | - Jennifer Rozier
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, OX3 7LF, UK
| | - Michael Coleman
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Catherine L Moyes
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, OX3 7LF, UK.
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Surendran SN, Jayadas TTP, Tharsan A, Thiruchenthooran V, Santhirasegaram S, Sivabalakrishnan K, Raveendran S, Ramasamy R. Anopheline bionomics, insecticide resistance and transnational dispersion in the context of controlling a possible recurrence of malaria transmission in Jaffna city in northern Sri Lanka. Parasit Vectors 2020; 13:156. [PMID: 32228675 PMCID: PMC7106892 DOI: 10.1186/s13071-020-04037-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 03/25/2020] [Indexed: 02/05/2023] Open
Abstract
Background Malaria was eliminated from Sri Lanka in 2013. However, the influx of infected travelers and the presence of potent anopheline vectors can re-initiate transmission in Jaffna city, which is separated by a narrow strait from the malaria-endemic Indian state of Tamil Nadu. Methods Anopheline larvae were collected from different habitats in Jaffna city and the susceptibility of emergent adults to DDT, malathion and deltamethrin investigated. Results Anopheline larvae were found in wells, surface-exposed drains, ponds, water puddles and water storage tanks, with many containing polluted, alkaline and brackish water. Anopheles culicifacies, An. subpictus, An. stephensi and An. varuna were identified in the collections. Adults of the four anopheline species were resistant to DDT. Anopheles subpictus and An. stephensi were resistant while An. culicifacies and An. varuna were possibly resistant to deltamethrin. Anopheles stephensi was resistant, An. subpictus possibly resistant while An. varuna and An. culicifacies were susceptible to malathion. DNA sequencing showed a L1014F (TTA to TTC) mutation in the IIS6 transmembrane segment of the voltage-gated sodium channel protein in deltamethrin-resistant An. subpictus—a mutation previously observed in India but not Sri Lanka. Conclusion Anopheles subpictus in Jaffna, like An. stephensi, may have recently originated in coastal Tamil Nadu. Besides infected overseas travelers, wind- and boat-borne carriage of Plasmodium-infected anophelines across the Palk Strait can potentially reintroduce malaria transmission to Jaffna city. Adaptation to diverse larval habitats and resistance to common insecticides in anophelines are identified as potential problems for vector control should this happen. ![]()
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Affiliation(s)
| | - Tibutius T P Jayadas
- Department of Zoology, Faculty of Science, University of Jaffna, Jaffna, Sri Lanka
| | - Annathurai Tharsan
- Department of Zoology, Faculty of Science, University of Jaffna, Jaffna, Sri Lanka
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Manel Yapabandara AMG, do Rosario de Fatima Mota M, Sarmento R, Bosco JD, Wickremasinghe R. From malaria control to elimination within a decade: lessons learned from Timor Leste, a newly independent country. Malar J 2020; 19:104. [PMID: 32127001 PMCID: PMC7055025 DOI: 10.1186/s12936-020-03162-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Accepted: 02/12/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Timor Leste has made remarkable progress from malaria control to malaria elimination in a span of 10 years during which organized malaria control efforts were instituted. The good practices and possible factors that have contributed to the remarkable transition from malaria control to elimination in a newly independent country devastated by civil unrest which left the entire administrative structure including the health sector in a disrupted non-functional state are highlighted. METHODS Data from the National Malaria Control Programme were reviewed. A literature search was carried out using the key words "malaria", "Timor Leste", "East Timor", and "malaria control" and "malaria elimination". All relevant manuscripts and reports that were identified in the search were reviewed. Key personnel of the NMCP, WHO and the GFATM involved in the project were interviewed. RESULTS With the setting up of the National Malaria Control Programme just after independence in 2003 with two officers, the programme expanded over the years and strategic malaria control activities in an organized manner commenced in 2009 with funding from the Global Fund to fight AIDS, Tuberculosis and Malaria. The incidence of malaria declined dramatically from 223,002 cases in 2006 with the last indigenous case being reported in June 2017. The decline in malaria was associated with strategic application of key evidence-based interventions taking into account the burden of disease, characteristics of vectors, and stratification of risk areas ensuring universal access to malaria prevention, and quality assured diagnostic tools and effective anti-malarial medicines at point of care, intensified surveillance, monitoring and evaluation, and capacity building, including training of staff, with adequate programme funding. The programme was provided with technical expertise and sustained political commitment that ensured uninterrupted implementation of interventions based on national strategic plans. The incorporation of the malaria control programme within an evolving health system helped the transition from malaria control to malaria elimination. CONCLUSION Universal access to quality assured malaria diagnosis and treatment and focussed vector control, implemented throughout the country in an organized manner with adequate funding and political commitment were key to the successful interruption of malaria transmission in the country. All the practices or factors listed did not work in isolation but rather synergistically in an integrated manner. Malaria elimination is possible even in tropical areas of South and Southeast Asia.
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Affiliation(s)
| | | | | | | | - Rajitha Wickremasinghe
- Department of Public Health, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka
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Metzger WG, Sulyok Z, Theurer A, Köhler C. [Development of malaria vaccines-state of the art]. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2020; 63:45-55. [PMID: 31828371 DOI: 10.1007/s00103-019-03070-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Weltweit leben 3,1 Mrd. Menschen in Gebieten, in denen Malaria endemisch ist (Tropen, Subtropen). Jährlich erkranken etwa 200 Mio. Menschen, ca. 500.000 sterben daran. Betroffen sind vor allem Kinder. Um die Malaria zu kontrollieren und schlussendlich jegliche Neuinfektion zu verhindern, ist die Entwicklung wirksamer Impfstoffe von großer Bedeutung. In diesem Beitrag werden zunächst Hintergrundinformationen zur Geschichte der Impfstoffentwicklung, zur Malariaerkrankung und zu den Möglichkeiten der Therapie und Ausbreitungskontrolle gegeben. Der Hauptteil widmet sich dem aktuellen Forschungsstand zu Impfstoffen gegen den Erreger Plasmodium falciparum, gefolgt von einer ausführlichen Diskussion. Malaria ist eine parasitäre Infektionskrankheit, die von Einzellern, sog. Plasmodien, verursacht wird. Es werden 5 humanpathogene Spezies unterschieden, von denen P. falciparum über 99 % der Erkrankungen in Afrika verursacht. Überträger (Vektor) ist die Anophelesmücke. Plasmodium bietet innerhalb seines Lebenszyklus verschiedene Ansatzpunkte für die Wirkung von Impfstoffen. Von den insgesamt ca. 70 Impfstoffkandidaten sind die präerythrozytären Impfstoffe, die in den Leberzyklus des Parasiten eingreifen, aktuell am weitesten entwickelt. Die von der Weltgesundheitsorganisation (WHO) angestrebte Wirksamkeit von mindestens 75 % wurde aber längst nicht erreicht. Mit RTS,S/AS01 wird derzeit erstmals ein mäßig wirksamer Impfstoff großflächig eingesetzt. Schon jetzt ist offensichtlich, dass die Malaria nur im Zusammenspiel mit anderen Maßnahmen eingedämmt werden kann. Expositionsprophylaxe mit imprägnierten Moskitonetzen, der Einsatz von Insektiziden mit Residualeffekt in Innenräumen (Indoor Residual Spraying), die Vernichtung von Moskitobrutplätzen und schnelle Diagnose und Therapie der Erkrankung sind hier wichtige Elemente ebenso wie eine funktionierende Gesundheitsversorgung, die in den von Armut geprägten Gebieten oft nicht gewährleistet ist.
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Ome-Kaius M, Kattenberg JH, Zaloumis S, Siba M, Kiniboro B, Jally S, Razook Z, Mantila D, Sui D, Ginny J, Rosanas-Urgell A, Karl S, Obadia T, Barry A, Rogerson SJ, Laman M, Tisch D, Felger I, Kazura JW, Mueller I, Robinson LJ. Differential impact of malaria control interventions on P. falciparum and P. vivax infections in young Papua New Guinean children. BMC Med 2019; 17:220. [PMID: 31813381 PMCID: PMC6900859 DOI: 10.1186/s12916-019-1456-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 10/29/2019] [Indexed: 12/21/2022] Open
Abstract
INTRODUCTION As malaria transmission declines, understanding the differential impact of intensified control on Plasmodium falciparum relative to Plasmodium vivax and identifying key drivers of ongoing transmission is essential to guide future interventions. METHODS Three longitudinal child cohorts were conducted in Papua New Guinea before (2006/2007), during (2008) and after scale-up of control interventions (2013). In each cohort, children aged 1-5 years were actively monitored for infection and illness. Incidence of malaria episodes, molecular force of blood-stage infections (molFOB) and population-averaged prevalence of infections were compared across the cohorts to investigate the impact of intensified control in young children and the key risk factors for malaria infection and illness in 2013. RESULTS Between 2006 and 2008, P. falciparum infection prevalence, molFOB, and clinical malaria episodes reduced by 47%, 59% and 69%, respectively, and a further 49%, 29% and 75% from 2008 to 2013 (prevalence 41.6% to 22.1% to 11.2%; molFOB: 3.4 to 1.4 to 1.0 clones/child/year; clinical episodes incidence rate (IR) 2.6 to 0.8 to IR 0.2 episodes/child/year). P. vivax clinical episodes declined at rates comparable to P. falciparum between 2006, 2008 and 2013 (IR 2.5 to 1.1 to 0.2), while P. vivax molFOB (2006, 9.8; 2008, 12.1) and prevalence (2006, 59.6%; 2008, 65.0%) remained high in 2008. However, in 2013, P. vivax molFOB (1.2) and prevalence (19.7%) had also substantially declined. In 2013, 89% of P. falciparum and 93% of P. vivax infections were asymptomatic, 62% and 47%, respectively, were sub-microscopic. Area of residence was the major determinant of malaria infection and illness. CONCLUSION Intensified vector control and routine case management had a differential impact on rates of P. falciparum and P. vivax infections but not clinical malaria episodes in young children. This suggests comparable reductions in new mosquito-derived infections but a delayed impact on P. vivax relapsing infections due to a previously acquired reservoir of hypnozoites. This demonstrates the need to strengthen implementation of P. vivax radical cure to maximise impact of control in co-endemic areas. The high heterogeneity of malaria in 2013 highlights the importance of surveillance and targeted interventions to accelerate towards elimination.
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Affiliation(s)
- Maria Ome-Kaius
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.,Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Johanna Helena Kattenberg
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.,Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Institute of Tropical Medicine, Antwerp, Belgium
| | - Sophie Zaloumis
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Matthew Siba
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Benson Kiniboro
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Shadrach Jally
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Zahra Razook
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Daisy Mantila
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Desmond Sui
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Jason Ginny
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | | | - Stephan Karl
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.,Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | | | - Alyssa Barry
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Stephen J Rogerson
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Moses Laman
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | | | - Ingrid Felger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | | | - Ivo Mueller
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, Australia.,Institut Pasteur, Paris, France
| | - Leanne J Robinson
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea. .,Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia. .,Department of Medical Biology, University of Melbourne, Melbourne, Australia. .,Burnet Institute, Melbourne, Australia.
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Toé KH, Mechan F, Tangena JAA, Morris M, Solino J, Tchicaya EFS, Traoré A, Ismail H, Maas J, Lissenden N, Pinder M, Lindsay SW, Tiono AB, Ranson H, Sagnon N. Assessing the impact of the addition of pyriproxyfen on the durability of permethrin-treated bed nets in Burkina Faso: a compound-randomized controlled trial. Malar J 2019; 18:383. [PMID: 31791332 PMCID: PMC6889366 DOI: 10.1186/s12936-019-3018-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 11/20/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Long-lasting insecticidal nets (LLINs) treated with pyrethroids are the foundation of malaria control in sub-Saharan Africa. Rising pyrethroid resistance in vectors, however, has driven the development of alternative net formulations. Here the durability of polyethylene nets with a novel combination of a pyrethroid, permethrin, and the insect juvenile hormone mimic, pyriproxyfen (PPF), compared to a standard permethrin LLIN, was assessed in rural Burkina Faso. METHODS A compound-randomized controlled trial was completed in two villages. In one village 326 of the PPF-permethrin nets (Olyset Duo) and 327 standard LLINs (Olyset) were distributed to assess bioefficacy. In a second village, 170 PPF-permethrin nets and 376 LLINs were distributed to assess survivorship. Nets were followed at 6-monthly intervals for 3 years. Bioefficacy was assessed by exposing permethrin-susceptible and resistant Anopheles gambiae sensu lato mosquito strains to standard World Health Organization (WHO) cone and tunnel tests with impacts on fertility measured in the resistant strain. Insecticide content was measured using high-performance liquid chromatography. LLIN survivorship was recorded with a questionnaire and assessed by comparing the physical integrity using the proportionate hole index (pHI). RESULTS The PPF-permethrin net met WHO bioefficacy criteria (≥ 80% mortality or ≥ 95% knockdown) for the first 18 months, compared to 6 months for the standard LLIN. Mean mosquito mortality for PPF-permethrin nets, across all time points, was 8.6% (CI 2.6-14.6%) higher than the standard LLIN. Fertility rates were reduced after PPF-permethrin net exposure at 1-month post distribution, but not later. Permethrin content of both types of nets remained within the target range of 20 g/kg ± 25% for 242/248 nets tested. The pyriproxyfen content of PPF-permethrin nets declined by 54%, from 10.4 g/kg (CI 10.2-10.6) to 4.7 g/kg (CI 3.5-6.0, p < 0.001) over 36 months. Net survivorship was poor, with only 13% of PPF-permethrin nets and 12% of LLINs still present in the original household after 36 months. There was no difference in the fabric integrity or survivorship between the two net types. CONCLUSION The PPF-permethrin net, Olyset Duo, met or exceeded the performance of the WHO-recommended standard LLIN (Olyset) in the current study but both net types failed the 3-year WHO bioefficacy criteria.
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Affiliation(s)
- Kobié H Toé
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Frank Mechan
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, UK
| | | | - Marion Morris
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Joanna Solino
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Emile F S Tchicaya
- Swiss Centre for Scientific Research in Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Alphonse Traoré
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Hanafy Ismail
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, UK
| | - James Maas
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Natalie Lissenden
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Margaret Pinder
- Department of Biosciences, Durham University, Durham, UK.,Medical Research Council Unit, The Gambia at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | | | - Alfred B Tiono
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Hilary Ranson
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, UK.
| | - N'Falé Sagnon
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
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Belay A, Petros B, Gebre-Michael T, Balkew M. Effect of LongRange™ eprinomectin on Anopheles arabiensis by feeding on calves treated with the drug. Malar J 2019; 18:332. [PMID: 31564253 PMCID: PMC6767632 DOI: 10.1186/s12936-019-2964-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 09/14/2019] [Indexed: 11/16/2022] Open
Abstract
Background Misuse of long-lasting insecticidal nets together with resistance of vectors to most of the insecticides for indoor residual spraying and impregnated nets threaten malaria vector control interventions, requiring search for alternative control methods. Reports have shown that Anopheles mosquitoes die when they feed on endectocidal drugs used to treat humans and animals. A study was designed to investigate the efficacy of LongRange™ (eprinomectin 5%) on laboratory reared Anopheles arabiensis fed on treated calves. Methods Anopheles arabiensis from insectary colony was fed on three calves treated with therapeutic dose of LongRange™ eprinomectin (1 ml/50 kg) and on non-treated three other calves as control arm. For the feeding, mosquitoes were placed in paper cups covered with nylon cloth mesh and then allowed to feed on the necks of calves. Subsequently, mosquito survival, fecundity, egg hatchability, larval development and adult emergence were recorded. Data were entered and analysed by using SPSS version 20. The Kaplan–Meier survival analysis and independent sample t-test were used. Results All mosquitoes that fed on LongRange™ Eprinomectin treated calves died within 7 days following blood ingestion. The drug also slightly affected fecundity and hatchability of An. arabiensis. Conclusion Treating livestock with LongRange™ (eprinomectin 5%) may serve as a supplementary control method for zoophagic An. arabiensis.
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Affiliation(s)
- Aklilu Belay
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia. .,Department of Microbial, Cellular & Molecular Biology, College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Beyene Petros
- Department of Microbial, Cellular & Molecular Biology, College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Teshome Gebre-Michael
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Meshesha Balkew
- Abt Associates, PMI VectorLink Project in Ethiopia, Addis Ababa, Ethiopia
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Aung PL, Silawan T, Rawiworrakul T, Min M. Perceived role and its enhancing factors among the village health volunteers regarding malaria control in rural myanmar. Indian J Public Health 2019; 62:10-14. [PMID: 29512559 DOI: 10.4103/ijph.ijph_432_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Background Village health volunteers (VHVs) are key agents for malaria control in community. The Myanmar Medical Association-Malaria (MMA-Malaria) Project has promoted effective malaria control in endemic and high-risk townships by supporting roles of VHVs. Objectives To assess the roles of VHVs on malaria control and factors enhancing their roles in rural Myanmar. Methods: A cross-sectional study was conducted in five townships where the MMA-Malaria Project has been implemented. One hundred and fifty VHVs were sampled from five townships by simple random sampling. Data were collected by trained interviewers using structured questionnaires, which covered sociodemographic, supportive, motivational factors, and roles of malaria control. Studied variables were described by proportions, means, and standard deviations and were analyzed for their association by odds ratio with 95% confidence interval and Chi-square tests. Results Most of VHVs (96%) expected to demonstrate good roles on malaria control, but only 44.0% exhibited current roles at a good level. Factors enhancing their roles were female (P = 0.037), family income ≥50,001 kyat/month (P < 0.015), time serving as a volunteer 1-2 years (P = 0.006), good knowledge of malaria control (P < 0.001), good family support (P < 0.001), good community support (P < 0.001), and good motivational factors (P = 0.002). Conclusion VHVs are key agents for malaria control in community. Most of VHVs expected to demonstrate good roles on malaria control, but less than half of them exhibited current roles at a good level. The systems and program for improving VHVs' knowledge, encouraging family and community support, and promoting motivation are essential for their better roles.
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Affiliation(s)
- P Linn Aung
- Dr and Deputy Project Manager, Medical Association - Malaria Project, Yangon, Myanmar
| | - Tassanee Silawan
- Assistant Professor and Dr, Departments of Community Health and Faculty of Public Health, Mahidol University, Bangkok, Thailand
| | - Tassanee Rawiworrakul
- Assistant Professor and Dr, Departments of Public Health Nursing, Faculty of Public Health, Mahidol University, Bangkok, Thailand
| | - Myo Min
- Dr and Programme Manager, Asia Pacific Malaria Elimination Network, Singapore
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