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Markwalter CF, Lapp Z, Abel L, Kimachas E, Omollo E, Freedman E, Chepkwony T, Amunga M, McCormick T, Bérubé S, Mangeni JN, Wesolowski A, Obala AA, Taylor SM, Prudhomme O'Meara W. Plasmodium falciparum infection in humans and mosquitoes influence natural Anopheline biting behavior and transmission. Nat Commun 2024; 15:4626. [PMID: 38816383 PMCID: PMC11139876 DOI: 10.1038/s41467-024-49080-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 05/22/2024] [Indexed: 06/01/2024] Open
Abstract
The human infectious reservoir of Plasmodium falciparum is governed by transmission efficiency during vector-human contact and mosquito biting preferences. Understanding biting bias in a natural setting can help target interventions to interrupt transmission. In a 15-month cohort in western Kenya, we detected P. falciparum in indoor-resting Anopheles and human blood samples by qPCR and matched mosquito bloodmeals to cohort participants using short-tandem repeat genotyping. Using risk factor analyses and discrete choice models, we assessed mosquito biting behavior with respect to parasite transmission. Biting was highly unequal; 20% of people received 86% of bites. Biting rates were higher on males (biting rate ratio (BRR): 1.68; CI: 1.28-2.19), children 5-15 years (BRR: 1.49; CI: 1.13-1.98), and P. falciparum-infected individuals (BRR: 1.25; CI: 1.01-1.55). In aggregate, P. falciparum-infected school-age (5-15 years) boys accounted for 50% of bites potentially leading to onward transmission and had an entomological inoculation rate 6.4x higher than any other group. Additionally, infectious mosquitoes were nearly 3x more likely than non-infectious mosquitoes to bite P. falciparum-infected individuals (relative risk ratio 2.76, 95% CI 1.65-4.61). Thus, persistent P. falciparum transmission was characterized by disproportionate onward transmission from school-age boys and by the preference of infected mosquitoes to feed upon infected people.
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Affiliation(s)
| | - Zena Lapp
- Duke Global Health Institute, Duke University, Durham, NC, USA
| | - Lucy Abel
- Academic Model Providing Access to Healthcare, Moi Teaching and Referral Hospital, Eldoret, Kenya
| | - Emmah Kimachas
- Academic Model Providing Access to Healthcare, Moi Teaching and Referral Hospital, Eldoret, Kenya
| | | | - Elizabeth Freedman
- Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, USA
| | - Tabitha Chepkwony
- Academic Model Providing Access to Healthcare, Moi Teaching and Referral Hospital, Eldoret, Kenya
| | - Mark Amunga
- Academic Model Providing Access to Healthcare, Moi Teaching and Referral Hospital, Eldoret, Kenya
| | - Tyler McCormick
- Departments of Statistics & Sociology, University of Washington, Seattle, WA, USA
| | - Sophie Bérubé
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Judith N Mangeni
- School of Public Health, College of Health Sciences, Moi University, Eldoret, Kenya
| | - Amy Wesolowski
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Andrew A Obala
- School of Medicine, College of Health Sciences, Moi University, Eldoret, Kenya
| | - Steve M Taylor
- Duke Global Health Institute, Duke University, Durham, NC, USA.
- Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, USA.
| | - Wendy Prudhomme O'Meara
- Duke Global Health Institute, Duke University, Durham, NC, USA.
- Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, USA.
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Soremekun S, Conteh B, Nyassi A, Soumare HM, Etoketim B, Ndiath MO, Bradley J, D'Alessandro U, Bousema T, Erhart A, Moreno M, Drakeley C. Household-level effects of seasonal malaria chemoprevention in the Gambia. COMMUNICATIONS MEDICINE 2024; 4:97. [PMID: 38778226 PMCID: PMC11111771 DOI: 10.1038/s43856-024-00503-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 04/18/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND In 2022 the WHO recommended the discretionary expansion of the eligible age range for seasonal malaria chemoprevention (SMC) to children older than 4 years. Older children are at lower risk of clinical disease and severe malaria so there has been uncertainty about the cost-benefit for national control programmes. However, emerging evidence from laboratory studies suggests protecting school-age children reduces the infectious reservoir for malaria and may significantly impact on transmission. This study aimed to assess whether these effects were detectable in the context of a routinely delivered SMC programme. METHODS In 2021 the Gambia extended the maximum eligible age for SMC from 4 to 9 years. We conducted a prospective population cohort study over the 2021 malaria transmission season covering 2210 inhabitants of 10 communities in the Upper River Region, and used a household-level mixed modelling approach to quantify impacts of SMC on malaria transmission. RESULTS We demonstrate that the hazard of clinical malaria in older participants aged 10+ years ineligible for SMC decreases by 20% for each additional SMC round per child 0-9 years in the same household. Older inhabitants also benefit from reduced risk of asymptomatic infections in high SMC coverage households. Spatial autoregression tests show impacts are highly localised, with no detectable spillover from nearby households. CONCLUSIONS Evidence for the transmission-reducing effects of extended-age SMC from routine programmes implemented at scale has been previously limited. Here we demonstrate benefits to the entire household, indicating such programmes may be more cost-effective than previously estimated.
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Affiliation(s)
- Seyi Soremekun
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK.
| | - Bakary Conteh
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Abdoullah Nyassi
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Harouna M Soumare
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Blessed Etoketim
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Mamadou Ousmane Ndiath
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - John Bradley
- Medical Research Council International Statistics and Epidemiology Group, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK
| | - Umberto D'Alessandro
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Teun Bousema
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Annette Erhart
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Marta Moreno
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK
| | - Chris Drakeley
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK.
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Graumans W, Ayo D, van Lieshout N, Lanke K, Bousema T, Arinaitwe E. Plasmodium malariae and Plasmodium ovale-Prevalent and Relevant. J Infect Dis 2024; 229:1239-1240. [PMID: 38243611 PMCID: PMC11011154 DOI: 10.1093/infdis/jiae015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 01/16/2024] [Indexed: 01/21/2024] Open
Affiliation(s)
- Wouter Graumans
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, the Netherlands
| | - Daniel Ayo
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Nadeche van Lieshout
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, the Netherlands
| | - Kjerstin Lanke
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, the Netherlands
| | - Teun Bousema
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, the Netherlands
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, United Kingdom
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Friedman-Klabanoff DJ, Adu-Gyasi D, Asante KP. Malaria prevention in children: an update. Curr Opin Pediatr 2024; 36:164-170. [PMID: 38299986 PMCID: PMC10932812 DOI: 10.1097/mop.0000000000001332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
PURPOSE OF REVIEW Malaria cases and deaths decreased from 2000 to 2015 but remain increased since 2019. Several new developments and strategies could help reverse this trend. The purpose of this review is to discuss new World Health Organization (WHO) guidelines and recent research on malaria prevention in children. RECENT FINDINGS Fifteen countries have now rolled out seasonal malaria chemoprophylaxis (SMC) in children at highest risk for severe malaria, and new WHO recommendations provide more flexibility for SMC implementation in terms of target age groups, geographic region, and number of cycles. Recent studies confirm that malaria burden in school aged children, and their contribution to transmission, is high. New guidelines permit expanded chemoprevention options for these children. Two vaccines have been approved for use in malaria endemic countries, RTS,S/AS01 E and R21/Matrix-M. Additionally, pyrethroid-chlorfenapyr bed nets are being deployed to combat resistant mosquitoes. SUMMARY While challenges remain in malaria control towards elimination, new guidelines and recently approved vaccines offer hope. Monitoring for continued vaccine and chemoprevention effectiveness, and for possible epidemiologic shifts in severe malaria presentation and deaths as additional prevention efforts roll out will be paramount.
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Affiliation(s)
- DeAnna J Friedman-Klabanoff
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dennis Adu-Gyasi
- Kintampo Health Research Centre, Research and Development Division, Ghana Health Service, Kintampo North Municipality, Bono East Region, Ghana
- Centre for Research in Applied Biology, School of Sciences, University of Energy and Natural Resources, Sunyani, Bono Region, Ghana, West Africa
| | - Kwaku Poku Asante
- Kintampo Health Research Centre, Research and Development Division, Ghana Health Service, Kintampo North Municipality, Bono East Region, Ghana
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Kayiba NK, Nitahara Y, Tshibangu-Kabamba E, Mbuyi DK, Kabongo-Tshibaka A, Kalala NT, Tshiebue BM, Candray-Medina KS, Kaku N, Nakagama Y, Speybroeck N, Mumba DN, Disashi GT, Kaneko A, Kido Y. Malaria infection among adults residing in a highly endemic region from the Democratic Republic of the Congo. Malar J 2024; 23:82. [PMID: 38500094 PMCID: PMC10946143 DOI: 10.1186/s12936-024-04881-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 02/15/2024] [Indexed: 03/20/2024] Open
Abstract
BACKGROUND Adults infected with Plasmodium spp. in endemic areas need to be re-evaluated in light of global malaria elimination goals. They potentially undermine malaria interventions but remain an overlooked aspect of public health strategies. METHODS This study aimed to estimate the prevalence of Plasmodium spp. infections, to identify underlying parasite species, and to assess predicting factors among adults residing in an endemic area from the Democratic Republic of Congo (DRC). A community-based cross-sectional survey in subjects aged 18 years and above was therefore carried out. Study participants were interviewed using a standard questionnaire and tested for Plasmodium spp. using a rapid diagnostic test and a nested polymerase chain reaction assay. Logistic regression models were fitted to assess the effect of potential predictive factors for infections with different Plasmodium spp. RESULTS Overall, 420 adults with an estimated prevalence of Plasmodium spp. infections of 60.2% [95% CI 55.5; 64.8] were included. Non-falciparum species infected 26.2% [95% CI 22.2; 30.5] of the study population. Among infected participants, three parasite species were identified, including Plasmodium falciparum (88.5%), Plasmodium malariae (39.9%), and Plasmodium ovale (7.5%) but no Plasmodium vivax. Mixed species accounted for 42.3% of infections while single-species infections predominated with P. falciparum (56.5%) among infected participants. All infected participants were asymptomatic at the time of the survey. Adults belonging to the "most economically disadvantaged" households had increased risks of infections with any Plasmodium spp. (adjusted odds ratio, aOR = 2.87 [95% CI 1.66, 20.07]; p < 0.001), compared to those from the "less economically disadvantaged" households. Conversely, each 1 year increase in age reduced the risk of infections with any Plasmodium spp. (aOR = 0.99 [95% CI 0.97, 0.99]; p = 0.048). Specifically for non-falciparum spp., males had increased risks of infection than females (aOR = 1.83 [95% CI 1.13, 2.96]; p = 0.014). CONCLUSION Adults infected with malaria constitute a potentially important latent reservoir for the transmission of the disease in the study setting. They should specifically be taken into account in public health measures and translational research.
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Affiliation(s)
- Nadine Kalenda Kayiba
- Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Department of Public Health, Faculty of Medicine - Pharmacy and Public Health, University of Mbujimayi, Mbuji Mayi, Democratic Republic of Congo
- Research Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - Yuko Nitahara
- Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
| | - Evariste Tshibangu-Kabamba
- Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Department of Internal Medicine, Faculty of Medicine - Pharmacy and Public Health, University of Mbujimayi, Mbuji Mayi, Democratic Republic of Congo
| | - Denis Kalambayi Mbuyi
- Department of Internal Medicine, Faculty of Medicine - Pharmacy and Public Health, University of Mbujimayi, Mbuji Mayi, Democratic Republic of Congo
| | - Augustin Kabongo-Tshibaka
- Department of Internal Medicine, Faculty of Medicine - Pharmacy and Public Health, University of Mbujimayi, Mbuji Mayi, Democratic Republic of Congo
- Department of Molecular Infection Dynamics, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Nestor Tshituka Kalala
- Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Department of Public Health, Faculty of Medicine - Pharmacy and Public Health, University of Mbujimayi, Mbuji Mayi, Democratic Republic of Congo
| | - Barthélemy Mukenga Tshiebue
- Department of Internal Medicine, Faculty of Medicine - Pharmacy and Public Health, University of Mbujimayi, Mbuji Mayi, Democratic Republic of Congo
| | - Katherine-Sofia Candray-Medina
- Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
| | - Natsuko Kaku
- Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
| | - Yu Nakagama
- Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
| | - Niko Speybroeck
- Research Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - Dieudonné Ngoyi Mumba
- Department of Parasitology, Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of Congo
| | - Ghislain Tumba Disashi
- Department of Internal Medicine, Faculty of Medicine - Pharmacy and Public Health, University of Mbujimayi, Mbuji Mayi, Democratic Republic of Congo
| | - Akira Kaneko
- Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Yasutoshi Kido
- Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan.
- Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan.
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Moreno M, Barry A, Gmeiner M, Yaro JB, Sermé SS, Byrne I, Ramjith J, Ouedraogo A, Soulama I, Grignard L, Soremekun S, Koele S, Ter Heine R, Ouedraogo AZ, Sawadogo J, Sanogo E, Ouedraogo IN, Hien D, Sirima SB, Bradley J, Bousema T, Drakeley C, Tiono AB. Understanding and maximising the community impact of seasonal malaria chemoprevention in Burkina Faso (INDIE-SMC): study protocol for a cluster randomised evaluation trial. BMJ Open 2024; 14:e081682. [PMID: 38479748 PMCID: PMC10936478 DOI: 10.1136/bmjopen-2023-081682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 02/19/2024] [Indexed: 03/26/2024] Open
Abstract
INTRODUCTION Seasonal malaria chemoprevention (SMC) involves repeated administrations of sulfadoxine-pyrimethamine plus amodiaquine to children below the age of 5 years during the peak transmission season in areas of seasonal malaria transmission. While highly impactful in reducing Plasmodium falciparum malaria burden in controlled research settings, the impact of SMC on infection prevalence is moderate in real-life settings. It remains unclear what drives this efficacy decay. Recently, the WHO widened the scope for SMC to target all vulnerable populations. The Ministry of Health (MoH) in Burkina Faso is considering extending SMC to children below 10 years old. We aim to assess the impact of SMC on clinical incidence and parasite prevalence and quantify the human infectious reservoir for malaria in this population. METHODS AND ANALYSIS We will perform a cluster randomised trial in Saponé Health District, Burkina Faso, with three study arms comprising 62 clusters of three compounds: arm 1 (control): SMC in under 5-year-old children, implemented by the MoH without directly observed treatment (DOT) for the full course of SMC; arm 2 (intervention): SMC in under 5-year-old children, with DOT for the full course of SMC; arm 3 (intervention): SMC in under 10-year-old children, with DOT for the full course of SMC. The primary endpoint is parasite prevalence at the end of the malaria transmission season. Secondary endpoints include the impact of SMC on clinical incidence. Factors affecting SMC uptake, treatment adherence, drug concentrations, parasite resistance markers and transmission of parasites will be determined. ETHICS AND DISSEMINATION The London School of Hygiene & Tropical Medicine's Ethics Committee (29193) and the Burkina Faso National Medical Ethics Committee (Deliberation No 2023-05-104) approved this study. The findings will be presented to the community; disease occurrence data and study outcomes will also be shared with the Burkina Faso MoH. Findings will be published irrespective of their results. TRIAL REGISTRATION NUMBER NCT05878366.
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Affiliation(s)
- Marta Moreno
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Aissata Barry
- Groupe de Recherche Action en Santé, Ouagadougou, Burkina Faso
| | - Markus Gmeiner
- Department of Medical Microbiology, Radboud University Nijmegen, Nijmegen, The Netherlands
| | | | - Samuel S Sermé
- Groupe de Recherche Action en Santé, Ouagadougou, Burkina Faso
| | - Isabel Byrne
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Jordache Ramjith
- Department of Medical Microbiology, Radboud University Nijmegen, Nijmegen, The Netherlands
| | | | - Issiaka Soulama
- Groupe de Recherche Action en Santé, Ouagadougou, Burkina Faso
| | - Lynn Grignard
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Seyi Soremekun
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Simon Koele
- Department of Medical Microbiology, Radboud University Nijmegen, Nijmegen, The Netherlands
| | | | | | - Jean Sawadogo
- Groupe de Recherche Action en Santé, Ouagadougou, Burkina Faso
| | - Edith Sanogo
- Groupe de Recherche Action en Santé, Ouagadougou, Burkina Faso
| | | | - Denise Hien
- Groupe de Recherche Action en Santé, Ouagadougou, Burkina Faso
| | | | - John Bradley
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Teun Bousema
- Department of Medical Microbiology, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Chris Drakeley
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Alfred B Tiono
- Groupe de Recherche Action en Santé, Ouagadougou, Burkina Faso
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Jeang B, Zhong D, Lee MC, Atieli H, Yewhalaw D, Yan G. Molecular surveillance of Kelch 13 polymorphisms in Plasmodium falciparum isolates from Kenya and Ethiopia. Malar J 2024; 23:36. [PMID: 38287365 PMCID: PMC10823687 DOI: 10.1186/s12936-023-04812-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 11/30/2023] [Indexed: 01/31/2024] Open
Abstract
BACKGROUND Timely molecular surveillance of Plasmodium falciparum kelch 13 (k13) gene mutations is essential for monitoring the emergence and stemming the spread of artemisinin resistance. Widespread artemisinin resistance, as observed in Southeast Asia, would reverse significant gains that have been made against the malaria burden in Africa. The purpose of this study was to assess the prevalence of k13 polymorphisms in western Kenya and Ethiopia at sites representing varying transmission intensities between 2018 and 2022. METHODS Dried blood spot samples collected through ongoing passive surveillance and malaria epidemiological studies, respectively, were investigated. The k13 gene was genotyped in P. falciparum isolates with high parasitaemia: 775 isolates from four sites in western Kenya (Homa Bay, Kakamega, Kisii, and Kombewa) and 319 isolates from five sites across Ethiopia (Arjo, Awash, Gambella, Dire Dawa, and Semera). DNA sequence variation and neutrality were analysed within each study site where mutant alleles were detected. RESULTS Sixteen Kelch13 haplotypes were detected in this study. Prevalence of nonsynonymous k13 mutations was low in both western Kenya (25/783, 3.19%) and Ethiopia (5/319, 1.57%) across the study period. Two WHO-validated mutations were detected: A675V in three isolates from Kenya and R622I in four isolates from Ethiopia. Seventeen samples from Kenya carried synonymous mutations (2.17%). No synonymous mutations were detected in Ethiopia. Genetic variation analyses and tests of neutrality further suggest an excess of low frequency polymorphisms in each study site. Fu and Li's F test statistic in Semera was 0.48 (P > 0.05), suggesting potential population selection of R622I, which appeared at a relatively high frequency (3/22, 13.04%). CONCLUSIONS This study presents an updated report on the low frequency of k13 mutations in western Kenya and Ethiopia. The WHO-validated R622I mutation, which has previously only been reported along the north-west border of Ethiopia, appeared in four isolates collected from eastern Ethiopia. The rapid expansion of R622I across Ethiopia signals the need for enhanced monitoring of the spread of drug-resistant P. falciparum parasites in East Africa. Although ACT remains currently efficacious in the study areas, continued surveillance is necessary to detect early indicators of artemisinin partial resistance.
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Affiliation(s)
- Brook Jeang
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - Daibin Zhong
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - Ming-Chieh Lee
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - Harrysone Atieli
- School of Public Health and Community Development, Maseno University, Kisumu, Kenya
- International Center of Excellence for Malaria Research, Tom Mboya University College, Homa Bay, Kenya
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Guiyun Yan
- Program in Public Health, University of California Irvine, Irvine, CA, USA.
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8
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Omondi S, Kosgei J, Musula G, Muchoki M, Abong'o B, Agumba S, Ogwang C, McDermott DP, Donnelly MJ, Staedke SG, Schultz J, Gutman JR, Gimnig JE, Ochomo E. Late morning biting behaviour of Anopheles funestus is a risk factor for transmission in schools in Siaya, western Kenya. Malar J 2023; 22:366. [PMID: 38037026 PMCID: PMC10691009 DOI: 10.1186/s12936-023-04806-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 11/23/2023] [Indexed: 12/02/2023] Open
Abstract
BACKGROUND Children in Kenya spend a substantial amount of time at school, including at dawn and dusk when mosquitoes are active. With changing vector behaviour towards early morning biting, it is important to determine whether there is an additional risk of transmission in schools. This study sought to understand whether late morning biting by Anopheles funestus, previously documented in households in western Kenya, was replicated in schools. METHODS From the 4th to the 6th of August 2023, human landing collections were conducted hourly in four schools in Alego Usonga sub-County, Siaya County. The collections were conducted in and outside five classrooms in each school and ran for 17 h, starting at 18:00 until 11:00 h the next morning. RESULTS Anopheles funestus was the predominant species collected, forming 93.2% (N = 727) of the entire collection, with peak landing between 06:00 and 07:00 h and continuing until 11:00 h. More than half of the collected An. funestus were either fed or gravid, potentially indicative of multiple bloodmeals within each gonotrophic cycle, and had a sporozoite rate of 2.05%. CONCLUSION School children spend up to 10 h of their daytime in schools, reporting between 06:00 and 07:00 h and staying in school until as late as 17:00 h, meaning that they receive potentially infectious mosquito bites during the morning hours in these settings. There is a need to consider vector control approaches targeting schools and other peridomestic spaces in the morning hours when An. funestus is active.
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Affiliation(s)
- Seline Omondi
- Entomology Section, Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Jackline Kosgei
- Entomology Section, Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - George Musula
- Entomology Section, Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Margaret Muchoki
- Entomology Section, Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Bernard Abong'o
- Entomology Section, Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Silas Agumba
- Entomology Section, Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Caroline Ogwang
- Entomology Section, Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Daniel P McDermott
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Martin J Donnelly
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Sarah G Staedke
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Jonathan Schultz
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30333, USA
| | - Julie R Gutman
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30333, USA
| | - John E Gimnig
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30333, USA
| | - Eric Ochomo
- Entomology Section, Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya.
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9
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Biruksew A, Demeke A, Birhanu Z, Golassa L, Getnet M, Yewhalaw D. Schoolchildren with asymptomatic malaria are potential hotspot for malaria reservoir in Ethiopia: implications for malaria control and elimination efforts. Malar J 2023; 22:311. [PMID: 37845680 PMCID: PMC10580533 DOI: 10.1186/s12936-023-04736-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 09/30/2023] [Indexed: 10/18/2023] Open
Abstract
BACKGROUND Schoolchildren with asymptomatic malaria infections often go undiagnosed and untreated, serving as reservoirs for infection that hamper malaria control and elimination efforts. In this context, little is known about the magnitude of asymptomatic malaria infections in apparently healthy schoolchildren in Ethiopia. This study was aimed at determining the prevalence of asymptomatic malaria infection and its associated factors in apparently healthy schoolchildren in Ethiopia. METHODS From September 2021 to January 2022, a school-based cross-sectional study was conducted on 994 apparently healthy schoolchildren (aged 6-15 years) selected from 21 primary schools in the Gomma district, of Jimma zone, southwestern Oromia, Ethiopia. A multi-stage sampling technique was used to select schools and participants. After allocating the total sample proportionally to each school and then to each grade, participants were selected using the lottery method from a list of student records (rosters). Finger-pricked blood samples were collected for microscopy blood film preparation and malaria rapid diagnostic test (RDT) (SD Bioline Malaria Ag Pf/Pv). Moreover, dry blood spots (DBSs) were prepared onto filter papers for quantitative real time polymerase chain reaction (qPCR) analysis. RESULTS As determined by RDT and microscopy, the prevalence of asymptomatic malaria was 2.20% and 1.51%, respectively. Using qPCR, the overall prevalence was 5.03% (50/994). Of this, Plasmodium falciparum, Plasmodium vivax and mixed infections accounted for 90%, 6% and 4%, respectively. Submicroscopic asymptomatic malaria infection was also accounted for 70% (35/50) of the overall prevalence. Household head age, nighttime outdoor activities of household heads, family history of malaria, absence of insecticide-treated nets (ITN), and presence of stagnant water around the houses are all significantly associated with asymptomatic malaria infections among schoolchildren. CONCLUSIONS This study found that both RDT and microscopy underestimated the prevalence of asymptomatic malaria in schoolchildren. However, qPCR was able to detect even low levels of parasitaemia and revealed a higher prevalence of asymptomatic submicroscopic malaria infections. The findings imply that schoolchildren with asymptomatic malaria infection are potential hotspot for malaria reservoir that fuels ongoing transmission. Therefore, it is imperative to include schoolchildren and schools in malaria intervention package and equally important is the adoption of more advanced and sensitive diagnostic tools, which would be crucial for successful malaria control and elimination efforts. Targeted interventions for asymptomatic malaria-infected schoolchildren can provide invaluable support to the National Malaria Control Programme in controlling and eventually eliminating the disease.
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Affiliation(s)
- Abdissa Biruksew
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIRC), Jimma University, Jimma, Ethiopia
| | | | - Zewdie Birhanu
- Department of Health, Behavior, and Society, Faculty of Public Health, Institute of Health Jimma University, Jimma, Ethiopia
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Masrie Getnet
- Department of Biostatistics and Epidemiology, Faculty of Public Health, Institute of Health, Jimma University, Jimma, Ethiopia
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIRC), Jimma University, Jimma, Ethiopia
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10
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Staedke SG, Maiteki-Sebuguzi C. Targeting malaria control to schoolchildren. Lancet Glob Health 2023; 11:e1156-e1157. [PMID: 37474216 DOI: 10.1016/s2214-109x(23)00238-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 05/10/2023] [Indexed: 07/22/2023]
Affiliation(s)
- Sarah G Staedke
- Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK; KEMRI Centre for Global Health Research, Kisumu, Kenya.
| | - Catherine Maiteki-Sebuguzi
- Infectious Diseases Research Collaboration, Kampala, Uganda; National Malaria Control Division, Ministry of Health, Kampala, Uganda
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11
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Simons LM, Ferrer P, Gombakomba N, Underwood K, Herrera R, Narum DL, Canepa G, Acquah F, Amoah L, Duffy PE, Barillas-Mury C, Long C, Lee SM, Locke E, Miura K, Williamson KC. Extending the range of Plasmodium falciparum transmission blocking antibodies. Vaccine 2023; 41:3367-3379. [PMID: 37100721 PMCID: PMC10334573 DOI: 10.1016/j.vaccine.2023.04.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 04/01/2023] [Accepted: 04/14/2023] [Indexed: 04/28/2023]
Abstract
Recent work demonstrating that asymptomatic carriers of P. falciparum parasites make up a large part of the infectious reservoir highlights the need for an effective malaria vaccine. Given the historical challenges of vaccine development, multiple parasite stages have been targeted, including the sexual stages required for transmission. Using flow cytometry to efficiently screen for P. falciparum gamete/zygote surface reactivity, we identified 82 antibodies that bound live P. falciparum gametes/zygotes. Ten antibodies had significant transmission-reducing activity (TRA) in a standard membrane feeding assay and were subcloned along with 9 nonTRA antibodies as comparators. After subcloning, only eight of the monoclonals obtained have significant TRA. These eight TRA mAbs do not recognize epitopes present in any of the current recombinant transmission-blocking vaccine candidates, Pfs230D1M, Pfs48/45.6C, Pf47 D2 and rPfs25. One TRA mAb immunoprecipitates two surface antigens, Pfs47 and Pfs230, that are expressed by both gametocytes and gametes/zygotes. These two proteins have not previously been reported to associate and the recognition of both by a single TRA mAb suggests the Pfs47/Pfs230 complex is a new vaccine target. In total, Pfs230 was the dominant target antigen, with five of the eight TRA mAbs and 8 of 11 nonTRA gamete/zygote surface reactive mAbs interacting with Pfs230. Of the three remaining TRA mAbs, two recognized non-reduced, parasite-produced Pfs25 and one bound non-reduced, parasite-produced Pfs48/45. None of the TRA mAbs bound protein on an immunoblot of reduced gamete/zygote extract and two TRA mAbs were immunoblot negative, indicating none of the new TRA epitopes are linear. The identification of eight new TRA mAbs that bind epitopes not included in any of the constructs currently under advancement as transmission-blocking vaccine candidates may provide new targets worthy of further study.
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Affiliation(s)
- Lacy M Simons
- Department of Biology, Loyola University Chicago, 1032 W Sheridan Rd, Chicago, IL 60660, USA
| | - Patricia Ferrer
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd., Bethesda, MD, 20814, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, 6720A Rockledge Drive, Suite 100, Bethesda, USA
| | - Nita Gombakomba
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd., Bethesda, MD, 20814, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, 6720A Rockledge Drive, Suite 100, Bethesda, USA
| | - Knashka Underwood
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd., Bethesda, MD, 20814, USA
| | - Raul Herrera
- Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, USA
| | - David L Narum
- Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, USA
| | - Gaspar Canepa
- Mosquito Immunity and Vector Competence Section Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD 20852, USA
| | - Festus Acquah
- Immunology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Linda Amoah
- Immunology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Patrick E Duffy
- Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, USA
| | - Carolina Barillas-Mury
- Mosquito Immunity and Vector Competence Section Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD 20852, USA
| | - Carole Long
- Malaria Immunology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD 20852, USA
| | - Shwu-Maan Lee
- Center for Vaccine Innovation and Access, PATH, 455 Massachusetts Ave, NW, Suite 1000, Washington, DC, 20001, USA
| | - Emily Locke
- Center for Vaccine Innovation and Access, PATH, 455 Massachusetts Ave, NW, Suite 1000, Washington, DC, 20001, USA
| | - Kazutoyo Miura
- Malaria Immunology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD 20852, USA
| | - Kim C Williamson
- Department of Biology, Loyola University Chicago, 1032 W Sheridan Rd, Chicago, IL 60660, USA; Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd., Bethesda, MD, 20814, USA.
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12
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Alemayehu A. Biology and epidemiology of Plasmodium falciparum and Plasmodium vivax gametocyte carriage: Implication for malaria control and elimination. Parasite Epidemiol Control 2023; 21:e00295. [PMID: 36950502 PMCID: PMC10025134 DOI: 10.1016/j.parepi.2023.e00295] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 01/01/2023] [Accepted: 02/27/2023] [Indexed: 03/09/2023] Open
Abstract
Malaria is among the leading public health problems worldwide. Female anopheles mosquito orchestrates the transmission of malaria by taking gametocytes and introducing sporozoite while taking blood meals. Interrupting transmission is the major strategy for malaria elimination. The gametocyte stage is essential for the onward transmission of malaria. Thus, understanding its basic biology and epidemiology is key to malaria control and elimination. Therefore, the current review focuses on revealing the biology, prevalence, and determinants of gametocyte carriage as well as its implication on mitigation of malaria. It also illustrates the role of asymptomatic and sub-microscopic Plasmodium infections and G-6-PD deficiency in gametocyte carriage and hence malaria transmission. Gametocytogenesis is initiated at committed merozoites and gives rise to the development of gametocytes. The trigger for gametocytogenesis depends on the host, parasite, and intervention factors. Gametocytes pass through five developmental stages identifiable by molecular markers. A considerable number of malaria patients carry gametocytes at a sub-microscopic level, thereby serving as a potential infectious reservoir of transmission. Factors involving the human host, Plasmodium parasite, and intervention parameters play a critical role in gametocyte biology and prevalence. The contribution of asymptomatic and sub-microscopic infections to malaria transmission is unknown. The clear impact of G-6-PD deficiency on malaria control and elimination remains unclear. Lack of clarity on such issues might impede the success of interventions. Basic science and epidemiological studies should continue to overcome the challenges and cope with the ever-evolving parasite and guide interventions.
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Affiliation(s)
- Aklilu Alemayehu
- School of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
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13
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Blanken SL, Soumare HDM, Andolina C, Lanke K, Bousema T. How to Interpret Parasite Persistence and Transmission to Mosquitoes After Antimalarial Treatment in Kenya? Clin Infect Dis 2023; 76:555-557. [PMID: 36069392 DOI: 10.1093/cid/ciac740] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/02/2022] [Indexed: 11/14/2022] Open
Affiliation(s)
- Sara Lynn Blanken
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Harouna Dit Massire Soumare
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Chiara Andolina
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Kjerstin Lanke
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Teun Bousema
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
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14
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Andagalu B, Watson OJ, Onyango I, Opot B, Okoth R, Chemwor G, Sifuna P, Juma D, Cheruiyot A, Yeda R, Okudo C, Wafubwa J, Yalwala S, Abuom D, Ogutu B, Cowden J, Akala HM, Kamau E. Reply to Blanken et al. Clin Infect Dis 2023; 76:557-559. [PMID: 36069376 DOI: 10.1093/cid/ciac741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/26/2022] [Accepted: 09/02/2022] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ben Andagalu
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Oliver J Watson
- Medical Research Council, Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Irene Onyango
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Benjamin Opot
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Raphael Okoth
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Gladys Chemwor
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Peter Sifuna
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Dennis Juma
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Agnes Cheruiyot
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Redemptah Yeda
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Charles Okudo
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Jackline Wafubwa
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Santos Yalwala
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - David Abuom
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | | | - Jessica Cowden
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Hoseah M Akala
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Edwin Kamau
- Department of Emerging and Infectious Diseases, United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
- Department of Pathology and Area Laboratory Services, Tripler Army Medical Center, Honolulu, Hawaii, USA
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15
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Chemoprevention for the Populations of Malaria Endemic Africa. Diseases 2022; 10:diseases10040101. [PMID: 36412595 PMCID: PMC9680511 DOI: 10.3390/diseases10040101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 10/20/2022] [Accepted: 10/26/2022] [Indexed: 11/11/2022] Open
Abstract
Drugs have been used to prevent malaria for centuries, but only recently have they been used on a large scale to prevent malaria in the resident population of malaria endemic areas in sub-Saharan Africa. This paper discusses some of the reasons for the hesitancy in adoption of chemopreventive strategies in sub-Saharan Africa, reasons why this hesitancy has been overcome in recent years and the range of target groups now identified by the World Health Organization as those who can benefit most from chemoprevention. Adoption of carefully targeted chemopreventive strategies could help reverse the recent stagnation in the decline in malaria in sub-Saharan Africa that had been taking place during the previous two decades.
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