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Schaffner SF, Badiane A, Khorgade A, Ndiop M, Gomis J, Wong W, Ndiaye YD, Diedhiou Y, Thwing J, Seck MC, Early A, Sy M, Deme A, Diallo MA, Sy N, Sene A, Ndiaye T, Sow D, Dieye B, Ndiaye IM, Gaye A, Ndiaye A, Battle KE, Proctor JL, Bever C, Fall FB, Diallo I, Gaye S, Sene D, Hartl DL, Wirth DF, MacInnis B, Ndiaye D, Volkman SK. Malaria surveillance reveals parasite relatedness, signatures of selection, and correlates of transmission across Senegal. Nat Commun 2023; 14:7268. [PMID: 37949851 PMCID: PMC10638404 DOI: 10.1038/s41467-023-43087-4] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 10/31/2023] [Indexed: 11/12/2023] Open
Abstract
We here analyze data from the first year of an ongoing nationwide program of genetic surveillance of Plasmodium falciparum parasites in Senegal. The analysis is based on 1097 samples collected at health facilities during passive malaria case detection in 2019; it provides a baseline for analyzing parasite genetic metrics as they vary over time and geographic space. The study's goal was to identify genetic metrics that were informative about transmission intensity and other aspects of transmission dynamics, focusing on measures of genetic relatedness between parasites. We found the best genetic proxy for local malaria incidence to be the proportion of polygenomic infections (those with multiple genetically distinct parasites), although this relationship broke down at low incidence. The proportion of related parasites was less correlated with incidence while local genetic diversity was uninformative. The type of relatedness could discriminate local transmission patterns: two nearby areas had similarly high fractions of relatives, but one was dominated by clones and the other by outcrossed relatives. Throughout Senegal, 58% of related parasites belonged to a single network of relatives, within which parasites were enriched for shared haplotypes at known and suspected drug resistance loci and at one novel locus, reflective of ongoing selection pressure.
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Affiliation(s)
- Stephen F Schaffner
- Infectious Disease and Microbiome Program, The Broad Institute, Cambridge, MA, USA
| | - Aida Badiane
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Akanksha Khorgade
- Infectious Disease and Microbiome Program, The Broad Institute, Cambridge, MA, USA
| | - Medoune Ndiop
- Programme National de Lutte Contre le Paludisme (PNLP), Dakar, Senegal
| | - Jules Gomis
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Wesley Wong
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Yaye Die Ndiaye
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Younouss Diedhiou
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Julie Thwing
- Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Mame Cheikh Seck
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Angela Early
- Infectious Disease and Microbiome Program, The Broad Institute, Cambridge, MA, USA
| | - Mouhamad Sy
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Awa Deme
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Mamadou Alpha Diallo
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Ngayo Sy
- Section de Lutte Anti-Parasitaire (SLAP) Clinic, Thies, Senegal
| | - Aita Sene
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Tolla Ndiaye
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Djiby Sow
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Baba Dieye
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Ibrahima Mbaye Ndiaye
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Amy Gaye
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Aliou Ndiaye
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Katherine E Battle
- Institute for Disease Modeling in Global Health, Bill and Melinda Gates Foundation, Seattle, WA, USA
| | - Joshua L Proctor
- Institute for Disease Modeling in Global Health, Bill and Melinda Gates Foundation, Seattle, WA, USA
| | - Caitlin Bever
- Institute for Disease Modeling in Global Health, Bill and Melinda Gates Foundation, Seattle, WA, USA
| | - Fatou Ba Fall
- Programme National de Lutte Contre le Paludisme (PNLP), Dakar, Senegal
| | - Ibrahima Diallo
- Programme National de Lutte Contre le Paludisme (PNLP), Dakar, Senegal
| | - Seynabou Gaye
- Programme National de Lutte Contre le Paludisme (PNLP), Dakar, Senegal
| | - Doudou Sene
- Programme National de Lutte Contre le Paludisme (PNLP), Dakar, Senegal
| | - Daniel L Hartl
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Dyann F Wirth
- Infectious Disease and Microbiome Program, The Broad Institute, Cambridge, MA, USA
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Bronwyn MacInnis
- Infectious Disease and Microbiome Program, The Broad Institute, Cambridge, MA, USA
| | - Daouda Ndiaye
- Centre International de recherche, de Formation en Genomique Appliquee et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Sarah K Volkman
- Infectious Disease and Microbiome Program, The Broad Institute, Cambridge, MA, USA.
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA.
- College of Natural, Behavioral, and Health Sciences, Simmons University, Boston, MA, USA.
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Schaffner SF, Badiane A, Khorgade A, Ndiop M, Gomis J, Wong W, Ndiaye YD, Diedhiou Y, Thwing J, Seck MC, Early A, Sy M, Deme A, Diallo MA, Sy N, Sene A, Ndiaye T, Sow D, Dieye B, Ndiaye IM, Gaye A, Ndiaye A, Battle KE, Proctor JL, Bever C, Fall FB, Diallo I, Gaye S, Sene D, Hartl DL, Wirth DF, MacInnis B, Ndiaye D, Volkman SK. Malaria surveillance reveals parasite relatedness, signatures of selection, and correlates of transmission across Senegal. medRxiv 2023:2023.04.11.23288401. [PMID: 37131838 PMCID: PMC10153316 DOI: 10.1101/2023.04.11.23288401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Parasite genetic surveillance has the potential to play an important role in malaria control. We describe here an analysis of data from the first year of an ongoing, nationwide program of genetic surveillance of Plasmodium falciparum parasites in Senegal, intended to provide actionable information for malaria control efforts. Looking for a good proxy for local malaria incidence, we found that the best predictor was the proportion of polygenomic infections (those with multiple genetically distinct parasites), although that relationship broke down in very low incidence settings (r = 0.77 overall). The proportion of closely related parasites in a site was more weakly correlated ( r = -0.44) with incidence while the local genetic diversity was uninformative. Study of related parasites indicated their potential for discriminating local transmission patterns: two nearby study areas had similarly high fractions of relatives, but one area was dominated by clones and the other by outcrossed relatives. Throughout the country, 58% of related parasites proved to belong to a single network of relatives, within which parasites were enriched for shared haplotypes at known and suspected drug resistance loci as well as at one novel locus, reflective of ongoing selection pressure.
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Ndiaye YD, Wong W, Thwing J, Schaffner SS, Tine A, Diallo MA, Deme A, Sy M, Bei AK, Thiaw AB, Daniels R, Ndiaye T, Gaye A, Ndiaye IM, Toure M, Gadiaga N, Sene A, Sow D, Garba MN, Yade MS, Dieye B, Diongue K, Zoumarou D, Ndiaye A, Gomis J, Fall FB, Ndiop M, Diallo I, Sene D, Macinnis B, Seck MC, Ndiaye M, Badiane AS, Hartl DL, Volkman SK, Wirth DF, Ndiaye D. Two decades of molecular surveillance in Senegal reveal changes in known drug resistance mutations associated with historical drug use and seasonal malaria chemoprevention. medRxiv 2023:2023.04.24.23288820. [PMID: 37163114 PMCID: PMC10168519 DOI: 10.1101/2023.04.24.23288820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Drug resistance in Plasmodium falciparum is a major threat to malaria control efforts. We analyzed data from two decades (2000-2020) of continuous molecular surveillance of P. falciparum parasite strains in Senegal to determine how historical changes in drug administration policy may have affected parasite evolution. We profiled several known drug resistance markers and their surrounding haplotypes using a combination of single nucleotide polymorphism (SNP) molecular surveillance and whole-genome sequence (WGS) based population genomics. We observed rapid changes in drug resistance markers associated with the withdrawal of chloroquine and introduction of sulfadoxine-pyrimethamine in 2003. We also observed a rapid increase in Pfcrt K76T and decline in Pfdhps A437G starting in 2014, which we hypothesize may reflect changes in resistance or fitness caused by seasonal malaria chemoprevention (SMC). Parasite populations evolve rapidly in response to drug use, and SMC preventive efficacy should be closely monitored.
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Affiliation(s)
- Yaye Die Ndiaye
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Wesley Wong
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA, 02115, USA
| | - Julie Thwing
- Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA ,30329, USA
| | - Stephen S Schaffner
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA, 02142, USA
| | - Abdoulaye Tine
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Mamadou Alpha Diallo
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Awa Deme
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Mouhammad Sy
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Amy K Bei
- Yale School of Public Health, 60 College St, New Haven, CT 06510
| | - Alphonse B Thiaw
- Department of biochemistry and Functional Genomics, Sherbrooke University, 2500 Bd de l'Universite, Sherbrooke, QC J1K 2R1, Canada
| | - Rachel Daniels
- RNA Therapeutics Institute, UMass Chan Medical School, 368 Plantation Street, Worcester MA 01605
| | - Tolla Ndiaye
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Amy Gaye
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Ibrahima Mbaye Ndiaye
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Mariama Toure
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Nogaye Gadiaga
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Aita Sene
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Djiby Sow
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Mamane N Garba
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Mamadou Samba Yade
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Baba Dieye
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Khadim Diongue
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Daba Zoumarou
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Aliou Ndiaye
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Jules Gomis
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Fatou Ba Fall
- Yale School of Public Health, 60 College St, New Haven, CT 06510
| | - Medoune Ndiop
- National Malaria Control Program (NMCP), Rue FN 20, Dakar 25270, Senegal
| | - Ibrahima Diallo
- National Malaria Control Program (NMCP), Rue FN 20, Dakar 25270, Senegal
| | - Doudou Sene
- National Malaria Control Program (NMCP), Rue FN 20, Dakar 25270, Senegal
| | - Bronwyn Macinnis
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA, 02142, USA
| | - Mame Cheikh Seck
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Mouhamadou Ndiaye
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Aida S Badiane
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
| | - Daniel L Hartl
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Avenue, Cambridge, MA, 02138 USA
| | - Sarah K Volkman
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA, 02115, USA
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA, 02142, USA
- Simmons University, 300 The Fenway, Boston, MA, 02115, USA
| | - Dyann F Wirth
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA, 02115, USA
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA, 02142, USA
| | - Daouda Ndiaye
- International Research Training Center on Genomics and Health Surveillance (CIGASS), Cheikh Anta Diop University, Dakar, 16477, Senegal
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA, 02115, USA
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Manga IA, BA MS, Tairou F, Seck A, Kouevidjin E, Sow D, Sylla K, Ndiaye M, Ba Fall F, Gueye AB, Diallo I, Ndiop M, Ba M, Tine RC, Gaye O, Faye B, Ndiaye JLA. Malaria parasite carriage before and two years after the implementation of seasonal malaria chemoprevention: a case study of the Saraya health district, southern Senegal. Wellcome Open Res 2022; 7:179. [PMID: 37521536 PMCID: PMC10375055 DOI: 10.12688/wellcomeopenres.17888.2] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/07/2022] [Indexed: 08/01/2023] Open
Abstract
Background : Seasonal malaria chemoprevention (SMC) has been adopted and implemented in the southern regions of Senegal in children aged between three and 120 months since 2013. Scaling up this strategy requires its evaluation to assess the impact. This study was carried out to determine the dynamics of Plasmodium falciparum carriage before and after two years of SMC implementation. Methods : Four household surveys were conducted in villages in the health district of Saraya, which is a SMC implementation area in Senegal. These villages were selected using probability proportional to size sampling. Each selected village was divided into segments containing at least 50 children. In each segment, a household questionnaire was administered to the parents or legal representatives of children aged three to 120 months. Blood smears were collected to determine P. falciparum prevalence by microscopy one month before the first round of SMC, one month after the last round of the first SMC campaign and two years after the start of the implementation. Results : A total of 2008 children were included with a mean average age of 4.81 (+/-2.73) years. Of the study population, 50.33% were more than five years old and 50.3% were male. In 2013, mosquito net ownership was 99.4 % before the SMC campaign and 97.4% after. In 2015, it was 36.6% before and 45.8% after the campaign. In 2013, the prevalence of plasmodium carriage was 11.8% before and 6.1% after the SMC campaign. In 2015, the prevalence was 4.9% before the administration of SMC and this increased up to 15.3% after. Malaria prevalence was high among children over five years old and in boys. Conclusions : The decrease in Plasmodium falciparum parasite prevalence, which subsequently increased after two years of SMC implementation in this study, suggests adding an extra cycle of the SMC or adjusting the administration period.
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Affiliation(s)
- Isaac Akhenaton Manga
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
| | - Mamadou Sarifou BA
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
- Ministry of Health and Social Action, Dakar, Senegal
| | - Fassiatou Tairou
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
| | - Amadou Seck
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
| | - Ekoue Kouevidjin
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
| | - Doudou Sow
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
| | - Khadime Sylla
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
| | - Magatte Ndiaye
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
| | | | | | | | | | - Mady Ba
- National Malaria Control Program, Dakar, Senegal
| | - Roger Clément Tine
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
| | - Omar Gaye
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
| | - Babacar Faye
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
| | - Jean Louis Abdourahim Ndiaye
- Parasitology-Mycology Department, Faculty of Medicine, Pharmacy and Ondontology, Cheikh Anta Diop University of Dakar, Dakar, Senegal
- Service of Parasitology Mycology, Department of Medical Biology, UFR Santé/University Iba Der Thiam, Thies, Senegal
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MANGA IA, BA MS, Tairou F, Seck A, Kouevidjin E, Sow D, Sylla K, Ndiaye M, Ba Fall F, Gueye AB, Diallo I, Ndiop M, Ba M, Tine RC, Gaye O, Faye B, Ndiaye JLA. Malaria parasite carriage before and two years after the implementation of seasonal malaria chemoprevention: a case study of the Saraya health district, southern Senegal. Wellcome Open Res 2022. [DOI: 10.12688/wellcomeopenres.17888.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: Seasonal malaria chemoprevention (SMC) has been adopted and implemented in the southern regions of Senegal in children aged between three and 120 months since 2013. Scaling up this strategy requires its evaluation to assess the impact. This study was carried out to determine the dynamics of Plasmodium falciparum carriage before and after two years of SMC implementation. Methods: Four household surveys were conducted in villages in the health district of Saraya, which is a SMC implementation area in Senegal. These villages were selected using probability proportional to size sampling. Each selected village was divided into segments containing at least 50 children. In each segment, a household questionnaire was administered to the parents or legal representatives of children aged three to 120 months. Blood smears were collected to determine P. falciparum prevalence by microscopy one month before the first round of SMC, one month after the last round of the first SMC campaign and two years after the start of the implementation. Results: A total of 2008 children were included with a mean average age of 4.81 (+/-2.73) years. Of the study population, 50.33% were more than five years old and 50.3% were male. In 2013, mosquito net ownership was 99.4 % before the SMC campaign and 97.4% after. In 2015, it was 36.6% before and 45.8% after the campaign. In 2013, the prevalence of plasmodium carriage was 11.8% before and 6.1% after the SMC campaign. In 2015, the prevalence was 4.9% before the administration of SMC and this increased up to 15.3% after. Malaria prevalence was high among children over five years old and in boys. Conclusions: The decrease in Plasmodium falciparum parasite prevalence, which subsequently increased after two years of SMC implementation in this study, suggests adding an extra cycle of the SMC or adjusting the administration period.
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Diouf M, Faye BT, Diouf EH, Dia AK, Konate A, Fall FB, Sene D, Diouf MB, Gadiaga L, Konate L, Dione DA, Tine RC, Faye O. Survival of eight LLIN brands 6, 12, 24 and 36 months after a mass distribution campaign in rural and urban settings in Senegal. BMC Public Health 2022; 22:719. [PMID: 35410149 PMCID: PMC9004050 DOI: 10.1186/s12889-022-13051-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [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: 08/08/2021] [Accepted: 03/22/2022] [Indexed: 11/16/2022] Open
Abstract
Background Long lasting insecticidal nets (LLIN) are one of the core components of global malaria prevention and control. The lifespan of LLIN varies widely depending on the population or environment, and randomized studies are required to compare LLIN inaccording to arbitrary thresholds households under different field conditions. This study investigated survival of different LLIN brands in Senegal. Methods Ten thousand six hundred eight LLINs were distributed in five regions, each stratified by rural and urban setting. As part of the longitudinal follow-up, 2222 nets were randomly sampled and monitored from 6 to 36 months. Using random effects for households, Bayesian models were used to estimate independent survival by net type (Interceptor®, Life Net®, MAGNet™, Netprotect®, Olyset® Net, PermaNet® 2.0 R, PermaNet® 2.0 C, Yorkool® LN) and by area (rural/urban). In addition to survival, median survival time and attrition of each LLIN brand was determined. Attrition was defined as nets that were missing because they were reported given away, destroyed and thrown away, or repurposed. Results Three net types had a proportion of survival above 80% after 24 months: Interceptor®87.8% (95% CI 80–93.4); conical PermaNet® 2.0 86.9% (95% CI 79.3–92.4) and Life Net® 85.6% (95% CI 75–93). At 36 months, conical PermaNet® 2.0 maintained a good survival rate, 79.5% (95% CI 65.9–88.8). The attrition due to redistributed nets showed that the two conical net types (PermaNet® 2.0 and Interceptor®) were more often retained by households and their median retention time was well above 3 years (median survival time = 3.5 years for PermaNet® 2.0 and median survival time = 4 years for Interceptor®). Despite this good retention, Interceptor® had weak physical integrity and its median survival due to wear and tear was below 3 years (median survival time = 2.4 years). The odds ratio of survival was 2.5 times higher in rural settings than in urban settings (OR 2.5; 95% CI 1.7–3.7). Conclusions Differences in survival among LLIN may be driven by brand, shape or environmental setting. In this study in Senegal, conical PermaNet® 2.0 were retained in households while rectangular PermaNet® 2.0 had lower retention, suggesting that net shape may play a role in retention and should be further investigated. Distribution of preferred LLIN shape, accompanied by good communication on care and repair, could lead to increased effective lifespan, and allow for longer intervals between universal coverage campaigns.
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Affiliation(s)
- Mbaye Diouf
- Laboratory of Vector and Parasite Ecology (UCAD), Dakar, Senegal.
| | | | - El Hadji Diouf
- Laboratory of Vector and Parasite Ecology (UCAD), Dakar, Senegal
| | | | - Abdoulaye Konate
- Laboratory of Vector and Parasite Ecology (UCAD), Dakar, Senegal
| | - Fatou Ba Fall
- National Malaria Control Program (NMCP/Senegal), Dakar, Senegal
| | - Doudou Sene
- National Malaria Control Program (NMCP/Senegal), Dakar, Senegal
| | - Mame Birame Diouf
- President's Malaria Initiative/ United State Agency International Development/Senegal (USAID/PMI), Dakar, Senegal
| | - Libasse Gadiaga
- National Malaria Control Program (NMCP/Senegal), Dakar, Senegal
| | - Lassana Konate
- Laboratory of Vector and Parasite Ecology (UCAD), Dakar, Senegal
| | - Demba Anta Dione
- Health and Development Solution-Africa (HDS-Africa/Dakar), Dakar, Senegal
| | - Roger Clément Tine
- President's Malaria Initiative/ United State Agency International Development/Senegal (USAID/PMI), Dakar, Senegal
| | - Ousmane Faye
- Laboratory of Vector and Parasite Ecology (UCAD), Dakar, Senegal
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Ndiaye YD, Hartl DL, McGregor D, Badiane A, Fall FB, Daniels RF, Wirth DF, Ndiaye D, Volkman SK. Genetic surveillance for monitoring the impact of drug use on Plasmodium falciparum populations. Int J Parasitol Drugs Drug Resist 2021; 17:12-22. [PMID: 34333350 PMCID: PMC8342550 DOI: 10.1016/j.ijpddr.2021.07.004] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/24/2021] [Accepted: 07/07/2021] [Indexed: 11/23/2022]
Abstract
The use of antimalarial drugs is an effective strategy in the fight against malaria. However, selection of drug resistant parasites is a constant threat to the continued use of this approach. Antimalarial drugs are used not only to treat infections but also as part of population-level strategies to reduce malaria transmission toward elimination. While there is strong evidence that the ongoing use of antimalarial drugs increases the risk of the emergence and spread of drug-resistant parasites, it is less clear how population-level use of drug-based interventions like seasonal malaria chemoprevention (SMC) or mass drug administration (MDA) may contribute to drug resistance or loss of drug efficacy. Critical to sustained use of drug-based strategies for reducing the burden of malaria is the surveillance of population-level signals related to transmission reduction and resistance selection. Here we focus on Plasmodium falciparum and discuss the genetic signatures of a parasite population that are correlated with changes in transmission and related to drug pressure and resistance as a result of drug use. We review the evidence for MDA and SMC contributing to malaria burden reduction and drug resistance selection and examine the use and impact of these interventions in Senegal. Throughout we consider best strategies for ongoing surveillance of both population and resistance signals in the context of different parasite population parameters. Finally, we propose a roadmap for ongoing surveillance during population-level drug-based interventions to reduce the global malaria burden.
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Affiliation(s)
| | | | - David McGregor
- Harvard T.H. Chan School of Public Health, Boston, MA, USA.
| | | | - Fatou Ba Fall
- Programme National de Lutte Contre le Paludisme, Senegal.
| | - Rachel F Daniels
- Harvard T.H. Chan School of Public Health, Boston, MA, USA; The Broad Institute, Cambridge, MA, USA.
| | - Dyann F Wirth
- Harvard T.H. Chan School of Public Health, Boston, MA, USA; The Broad Institute, Cambridge, MA, USA.
| | | | - Sarah K Volkman
- Harvard T.H. Chan School of Public Health, Boston, MA, USA; The Broad Institute, Cambridge, MA, USA; Simmons University, Boston, MA, USA.
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8
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Diallo MA, L'Ollivier C, Diongue K, Badiane AS, Kodio A, Tall ML, Sy M, Seck MC, Sene D, Ndiaye M, Fall FB, Ranque S, Ndiaye D. Spatiotemporal Dynamic of the RTS,S/AS01 Malaria Vaccine Target Antigens in Senegal. Am J Trop Med Hyg 2021; 105:1738-1746. [PMID: 34634772 DOI: 10.4269/ajtmh.21-0369] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/17/2021] [Indexed: 11/07/2022] Open
Abstract
The RTS,S/AS01 malaria vaccine confers only moderate protection against malaria. Evidence suggests that the effectiveness of the RTS,S/AS01 vaccine depends upon the parasite population genetics, specifically regarding the circumsporozoite protein haplotypes in the population. We investigated Plasmodium falciparum circumsporozoite protein (PfCSP) gene sequences from two endemic sites in 2018 in Senegal. The PfCSP sequences were compared with those retrieved from the Pf3k genome database. In the central repeat region of PfCSP, the distribution of haplotypes differed significantly between the two study sites (Fisher's exact test, P < 0.001). No 3D7 vaccine strain haplotype was observed in this locus. In the C-terminal region, there was no significant difference in haplotypes distribution between Kedougou and Diourbel (Fischer's exact test, P = 0.122). The 3D7 haplotype frequency was 8.4% in early samples (2001-2011), but then it contracted in the subsequent years. The extensive plasticity of the P. falciparum genes coding the RTS,S/AS01 vaccine target antigens may influence the immune responses to circulating alleles. Monitoring the genetic diversity baseline and its dynamics over time and space would be instrumental in rationally improving the malaria RTS,S/AS01 vaccine and/or its implementation schedule.
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Affiliation(s)
- Mamadou Alpha Diallo
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal.,Aristide Le Dantec University Hospital, Dakar, Senegal
| | - Coralie L'Ollivier
- Aix Marseille University, IRD, AP-HM, SSA, VITROME, Marseille, France.,IHU Méditerranée Infection, Marseille, France
| | - Khadim Diongue
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal.,Aristide Le Dantec University Hospital, Dakar, Senegal
| | - Aida Sadikh Badiane
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal.,Aristide Le Dantec University Hospital, Dakar, Senegal
| | - Aly Kodio
- Aix Marseille University, IRD, AP-HM, SSA, VITROME, Marseille, France.,IHU Méditerranée Infection, Marseille, France
| | | | - Mouhamad Sy
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal.,Aristide Le Dantec University Hospital, Dakar, Senegal
| | - Mame Cheikh Seck
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal.,Aristide Le Dantec University Hospital, Dakar, Senegal
| | - Doudou Sene
- IHU Méditerranée Infection, Marseille, France
| | - Mouhamadou Ndiaye
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal.,Aristide Le Dantec University Hospital, Dakar, Senegal
| | - Fatou Ba Fall
- National Malaria Control Program (NMCP), Dakar, Senegal
| | - Stéphane Ranque
- Aix Marseille University, IRD, AP-HM, SSA, VITROME, Marseille, France.,IHU Méditerranée Infection, Marseille, France
| | - Daouda Ndiaye
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal.,Aristide Le Dantec University Hospital, Dakar, Senegal
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9
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Sy M, Badiane AS, Deme AB, Gaye A, Ndiaye T, Fall FB, Siddle KJ, Dieye B, Ndiaye YD, Diallo MA, Diongue K, Seck MC, Ndiaye IM, Cissé M, Gueye AB, Sène D, Dieye Y, Souané T, MacInnis B, Volkman SK, Wirth DF, Ndiaye D. Genomic investigation of atypical malaria cases in Kanel, northern Senegal. Malar J 2021; 20:103. [PMID: 33608006 PMCID: PMC7893743 DOI: 10.1186/s12936-021-03637-x] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 02/09/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The diagnosis of malaria cases in regions where the malaria burden has decreased significantly and prevalence is very low is more challenging, in part because of reduced clinical presumption of malaria. The appearance of a cluster of malaria cases with atypical symptoms in Mbounguiel, a village in northern Senegal where malaria transmission is low, in September 2018 exemplifies this scenario. The collaboration between the National Malaria Control Programme (NMCP) at the Senegal Ministry of Health and the Laboratory of Parasitology and Mycology at Cheikh Anta Diop University worked together to evaluate this cluster of malaria cases using molecular and serological tools. METHODS Malaria cases were diagnosed primarily by rapid diagnostic test (RDT), and confirmed by photo-induced electron transfer-polymerase chain reaction (PET-PCR). 24 single nucleotide polymorphisms (SNPs) barcoding was used for Plasmodium falciparum genotyping. Unbiased metagenomic sequencing and Luminex-based multi-pathogen antibody and antigen profiling were used to assess exposure to other pathogens. RESULTS Nine patients, of 15 suspected cases, were evaluated, and all nine samples were found to be positive for P. falciparum only. The 24 SNPs molecular barcode showed the predominance of polygenomic infections, with identifiable strains being different from one another. All patients tested positive for the P. falciparum antigens. No other pathogenic infection was detected by either the serological panel or metagenomic sequencing. CONCLUSIONS This work, undertaken locally within Senegal as a collaboration between the NMCP and a research laboratory at University of Cheikh Anta Diop (UCAD) revealed that a cluster of malaria cases were caused by different strains of P. falciparum. The public health response in real time demonstrates the value of local molecular and genomics capacity in affected countries for disease control and elimination.
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Affiliation(s)
- Mouhamad Sy
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal.
| | - Aida Sadikh Badiane
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
| | - Awa Bineta Deme
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
| | - Amy Gaye
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
| | - Tolla Ndiaye
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
| | - Fatou Ba Fall
- Senegal National Malaria Control Programme, Dakar, Senegal
| | | | - Baba Dieye
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
| | - Yaye Die Ndiaye
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
| | - Mamadou Alpha Diallo
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
| | - Khadim Diongue
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
| | - Mame Cheikh Seck
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
| | - Ibrahima Mbaye Ndiaye
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
| | | | | | - Doudou Sène
- Senegal National Malaria Control Programme, Dakar, Senegal
| | - Yakou Dieye
- Malaria Control and Evaluation Partnership in Africa PATH-MACEPA, Dakar, Senegal
| | - Tamba Souané
- Malaria Control and Evaluation Partnership in Africa PATH-MACEPA, Dakar, Senegal
| | - Bronwyn MacInnis
- The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Sarah K Volkman
- The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
- College of Natural, Behavioral, and Health Sciences, Simmons University, Boston, MA, USA
| | - Dyann F Wirth
- The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Daouda Ndiaye
- Laboratory of Parasitology and Mycology, Aristide le Dantec Hospital, Cheikh Anta Diop University, Dakar, Senegal
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10
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Gaye S, Kibler J, Ndiaye JL, Diouf MB, Linn A, Gueye AB, Fall FB, Ndiop M, Diallo I, Cisse M, Ba M, Thwing J. Proactive community case management in Senegal 2014-2016: a case study in maximizing the impact of community case management of malaria. Malar J 2020; 19:166. [PMID: 32334581 PMCID: PMC7183580 DOI: 10.1186/s12936-020-03238-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 04/16/2020] [Indexed: 11/10/2022] Open
Abstract
The Senegal National Malaria Control Programme (NMCP) introduced home-based malaria management for all ages, with diagnosis by rapid diagnostic test (RDT) and treatment with artemisinin-based combination therapy (ACT) in 2008, expanding to over 2000 villages nationwide by 2014. With prise en charge à domicile (PECADOM), community health workers (CHWs) were available for community members to seek care, but did not actively visit households to find cases. A trial of a proactive model (PECADOM Plus), in which CHWs visited all households in their village weekly during transmission season to identify fever cases and offer case management, in addition to availability during the week for home-based management, found that CHWs detected and treated more cases in intervention villages, while the number of cases detected weekly decreased over the transmission season. The NMCP scaled PECADOM Plus to three districts in 2014 (132 villages), to a total of six districts in 2015 (246 villages), and to a total of 16 districts in 2016 (708 villages). A narrative case study with programmatic results is presented. During active sweeps over approximately 20 weeks, CHWs tested a mean of 77 patients per CHW in 2014, 89 patients per CHW in 2015, and 90 patients per CHW in 2016, and diagnosed a mean of 61, 61 and 43 patients with malaria per CHW in 2014, 2015 and 2016, respectively. The number of patients who sought care between sweeps increased, with a 104% increase in the number of RDTs performed and a 77% increase in the number of positive tests and patients treated with ACT during passive case detection. While the number of CHWs increased 7%, the number of patients receiving an RDT increased by 307% and the number of malaria cases detected and treated by CHWs increased 274%, from the year prior to PECADOM Plus introduction to its first year of implementation. Based on these results, approximately 700 additional CHWs in 24 new districts were added in 2017. This case study describes the process, results and lessons learned from Senegal’s implementation of PECADOM Plus, as well as guidance for other programmes considering introduction of this innovative strategy.
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Affiliation(s)
- Seynabou Gaye
- Senegal National Malaria Control Programme, Dakar, Senegal
| | | | - Jean Louis Ndiaye
- Laboratoire de Parasitologie et Mycologie Médicale, Université Cheikh Anta Diop, Dakar, Senegal
| | - Mame Birame Diouf
- United States Agency for International Development, Dakar, Senegal.,U.S. President's Malaria Initiative, Dakar, Senegal
| | - Annē Linn
- United States Agency for International Development, Washington, DC, USA.,U.S. President's Malaria Initiative, Washington, DC, USA
| | | | - Fatou Ba Fall
- Senegal National Malaria Control Programme, Dakar, Senegal
| | - Médoune Ndiop
- Senegal National Malaria Control Programme, Dakar, Senegal
| | | | | | - Mady Ba
- Senegal National Malaria Control Programme, Dakar, Senegal
| | - Julie Thwing
- Division of Parasitic Diseases and Malaria, Malaria Branch, Center for Global Health, Centers for Disease Control and Prevention (CDC) Atlanta, Atlanta, GA, USA.
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11
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Seck MC, Thwing J, Badiane AS, Rogier E, Fall FB, Ndiaye PI, Diongue K, Mbow M, Ndiaye M, Diallo MA, Gomis JF, Mbaye A, Ndiaye T, Gaye A, Sy M, Déme AB, Ndiaye YD, Ndiaye D. Analysis of anti-Plasmodium IgG profiles among Fulani nomadic pastoralists in northern Senegal to assess malaria exposure. Malar J 2020; 19:15. [PMID: 31931834 PMCID: PMC6958760 DOI: 10.1186/s12936-020-3114-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [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: 10/31/2019] [Accepted: 01/09/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Northern Senegal is a zone of very low malaria transmission, with an annual incidence of < 5/1000 inhabitants. This area, where the Senegal National Malaria Control Programme has initiated elimination activities, hosts Fulani, nomadic, pastoralists that spend the dry season in the south where malaria incidence is higher (150-450/1000 inhabitants) and return to the north with the first rains. Previous research demonstrated parasite prevalence of < 1% in this Fulani population upon return from the south, similar to that documented in the north in cross-sectional surveys. METHODS A modified snowball sampling survey of nomadic pastoralists was conducted in five districts in northern Senegal during September and October 2014. Demographic information and dried blood spots were collected. Multiplex bead-based assays were used to assess antibody responses to merozoite surface protein (MSP-119) antigen of the four primary Plasmodium species, as well as circumsporozoite protein (CSP) and liver stage antigen (LSA-1) of Plasmodium falciparum. RESULTS In the five study districts, 1472 individuals were enrolled, with a median age of 22 years (range 1 to 80 years). Thirty-two percent of subjects were under 14 years and 57% were male. The overall seroprevalence of P. falciparum MSP-119, CSP and LSA-1 antibodies were 45, 12 and 5%, respectively. Plasmodium falciparum MSP-119 antibody responses increased significantly with age in all study areas, and were significantly higher among males. The highest seroprevalence to P. falciparum antigens was observed in the Kanel district (63%) and the lowest observed in Podor (28%). Low seroprevalence was observed for non-falciparum species in all the study sites: 0.4, 0.7 and 1.8%, respectively, for Plasmodium ovale, Plasmodium vivax and Plasmodium malariae MSP-1. Antibody responses to P. vivax were observed in all study sites except Kanel. CONCLUSION Prevalence of P. falciparum MSP-119 antibodies and increases by study participant age provided data for low levels of exposure among this transient nomadic population. In addition, antibody responses to P. falciparum short half-life markers (CSP and LSA-1) and non-falciparum species were low. Further investigations are needed to understand the exposure of the Fulani population to P. vivax.
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Affiliation(s)
- Mame Cheikh Seck
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal. .,Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal.
| | - Julie Thwing
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30029, USA
| | - Aida Sadikh Badiane
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal.,Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Eric Rogier
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30029, USA
| | - Fatou Ba Fall
- Senegal National Malaria Control Programme, Dakar, Senegal
| | - Pape Ibrahima Ndiaye
- Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Khadim Diongue
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal.,Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Moustapha Mbow
- Department of Immunology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Mouhamadou Ndiaye
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal.,Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Mamadou Alpha Diallo
- Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Jules François Gomis
- Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Aminata Mbaye
- Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Tolla Ndiaye
- Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Aminata Gaye
- Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Mohamad Sy
- Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Awa Bineta Déme
- Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Yaye Die Ndiaye
- Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
| | - Daouda Ndiaye
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal.,Laboratory of Parasitology, Aristide Le Dantec Teaching Hospital, Dakar, Senegal
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12
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Seck MC, Badiane AS, Thwing J, Moss D, Fall FB, Gomis JF, Deme AB, Diongue K, Sy M, Mbaye A, Ndiaye T, Gaye A, Ndiaye YD, Diallo MA, Ndiaye D, Rogier E. Serological Data Shows Low Levels of Chikungunya Exposure in Senegalese Nomadic Pastoralists. Pathogens 2019; 8:pathogens8030113. [PMID: 31357631 PMCID: PMC6789836 DOI: 10.3390/pathogens8030113] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 07/18/2019] [Accepted: 07/21/2019] [Indexed: 12/28/2022] Open
Abstract
The chikungunya virus (CHIKV) is spread by Aedes aegypti and Ae. albopictus mosquitos worldwide; infection can lead to disease including joint pain, fever, and rash, with some convalescent persons experiencing chronic symptoms. Historically, CHIKV transmission has occurred in Africa and Asia, but recent outbreaks have taken place in Europe, Indonesia, and the Americas. From September to October 2014, a survey was undertaken with nomadic pastoralists residing in the northeast departments of Senegal. Blood dried on filter paper (dried blood spots; DBS) were collected from 1465 participants of all ages, and assayed for Immunoglobulin G (IgG) antibodies against CHIKV E1 antigen by a bead-based multiplex assay. The overall seroprevalence of all participants to CHIKV E1 was 2.7%, with no persons under 10 years of age found to be antibody positive. Above 10 years of age, clear increases of seroprevalence and IgG levels were observed with increasing age; 7.6% of participants older than 50 years were found to be positive for anti-CHIKV IgG. Reported net ownership, net usage, and gender were all non-significant explanatory variables of seropositivity. These data show a low-level historical exposure of this pastoralist population to CHIKV, with no evidence of recent CHIKV transmission in the past decade.
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Affiliation(s)
- Mame Cheikh Seck
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal.
| | - Aida Sadikh Badiane
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Julie Thwing
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
- President's Malaria Initiative, Atlanta, GA 30303, USA
| | - Delynn Moss
- Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
| | - Fatou Ba Fall
- Senegal National Malaria Control Program, Dakar 999066, Senegal
| | - Jules Francois Gomis
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Awa Bineta Deme
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Khadim Diongue
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Mohamed Sy
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Aminata Mbaye
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Tolla Ndiaye
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Aminata Gaye
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Yaye Die Ndiaye
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Mamadou Alpha Diallo
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Daouda Ndiaye
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar 12500, Senegal
| | - Eric Rogier
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
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13
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Seck MC, Thwing J, Fall FB, Gomis JF, Deme A, Ndiaye YD, Daniels R, Volkman SK, Ndiop M, Ba M, Ndiaye D. Malaria prevalence, prevention and treatment seeking practices among nomadic pastoralists in northern Senegal. Malar J 2017; 16:413. [PMID: 29029619 PMCID: PMC5640937 DOI: 10.1186/s12936-017-2055-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [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: 05/30/2017] [Accepted: 10/05/2017] [Indexed: 12/26/2022] Open
Abstract
Background Malaria transmission in Senegal is highly stratified, from low in the dry north to moderately high in the moist south. In northern Senegal, along the Senegal River Valley and in the Ferlo semi-desert region, annual incidence is less than five cases per 1000 inhabitants. Many nomadic pastoralists have permanent dwellings in the Ferlo Desert and Senegal River Valley, but spend dry season in the south with their herds, returning north when the rains start, leading to a concern that this population could contribute to ongoing transmission in the north. Methods A modified snowball sampling survey was conducted at six sites in northern Senegal to determine the malaria prevention and treatment seeking practices and parasite prevalence among nomadic pastoralists in the Senegal River Valley and the Ferlo Desert. Nomadic pastoralists aged 6 months and older were surveyed during September and October 2014, and data regarding demographics, access to care and preventive measures were collected. Parasite infection was detected using rapid diagnostic tests (RDTs), microscopy (thin and thick smears) and polymerase chain reaction (PCR). Molecular barcodes were determined by high resolution melting (HRM). Results Of 1800 participants, 61% were male. Sixty-four percent had at least one bed net in the household, and 53% reported using a net the night before. Only 29% had received a net from a mass distribution campaign. Of the 8% (142) who reported having had fever in the last month, 55% sought care, 20% of whom received a diagnostic test, one-third of which (n = 5) were reported to be positive. Parasite prevalence was 0.44% by thick smear and 0.50% by PCR. None of the molecular barcodes identified among the nomadic pastoralists had been previously identified in Senegal. Conclusions While access to and utilization of malaria control interventions among nomadic pastoralists was lower than the general population, parasite prevalence was lower than expected and sheds doubt on the perception that they are a source of ongoing transmission in the north. The National Malaria Control Program is making efforts to improve access to malaria prevention and case management for nomadic populations. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-2055-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mame Cheikh Seck
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Julie Thwing
- Malaria Branch, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, President's Malaria Initiative, Atlanta, GA, USA.
| | - Fatou Ba Fall
- Senegal National Malaria Control Program, Dakar, Senegal
| | - Jules Francois Gomis
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Awa Deme
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Yaye Die Ndiaye
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Rachel Daniels
- Harvard T.H Chan School of Public Health, Boston, MA, USA
| | | | - Medoune Ndiop
- Senegal National Malaria Control Program, Dakar, Senegal
| | - Mady Ba
- Senegal National Malaria Control Program, Dakar, Senegal
| | - Daouda Ndiaye
- Department of Parasitology, Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
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NDiaye JL, Cissé B, Ba EH, Gomis JF, Ndour CT, Molez JF, Fall FB, Sokhna C, Faye B, Kouevijdin E, Niane FK, Cairns M, Trape JF, Rogier C, Gaye O, Greenwood BM, Milligan PJM. Correction: Safety of Seasonal Malaria Chemoprevention (SMC) with Sulfadoxine-Pyrimethamine plus Amodiaquine when Delivered to Children under 10 Years of Age by District Health Services in Senegal: Results from a Stepped-Wedge Cluster Randomized Trial. PLoS One 2016; 11:e0168421. [PMID: 27930741 PMCID: PMC5145224 DOI: 10.1371/journal.pone.0168421] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
[This corrects the article DOI: 10.1371/journal.pone.0162563.].
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Cissé B, Ba EH, Sokhna C, NDiaye JL, Gomis JF, Dial Y, Pitt C, NDiaye M, Cairns M, Faye E, NDiaye M, Lo A, Tine R, Faye S, Faye B, Sy O, Konate L, Kouevijdin E, Flach C, Faye O, Trape JF, Sutherland C, Fall FB, Thior PM, Faye OK, Greenwood B, Gaye O, Milligan P. Effectiveness of Seasonal Malaria Chemoprevention in Children under Ten Years of Age in Senegal: A Stepped-Wedge Cluster-Randomised Trial. PLoS Med 2016; 13:e1002175. [PMID: 27875528 PMCID: PMC5119693 DOI: 10.1371/journal.pmed.1002175] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 10/06/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Seasonal Malaria Chemoprevention (SMC) with sulfadoxine-pyrimethamine (SP) plus amodiaquine (AQ), given each month during the transmission season, is recommended for children living in areas of the Sahel where malaria transmission is highly seasonal. The recommendation for SMC is currently limited to children under five years of age, but, in many areas of seasonal transmission, the burden in older children may justify extending this age limit. This study was done to determine the effectiveness of SMC in Senegalese children up to ten years of age. METHODS AND FINDINGS SMC was introduced into three districts over three years in central Senegal using a stepped-wedge cluster-randomised design. A census of the population was undertaken and a surveillance system was established to record all deaths and to record all cases of malaria seen at health facilities. A pharmacovigilance system was put in place to detect adverse drug reactions. Fifty-four health posts were randomised. Nine started implementation of SMC in 2008, 18 in 2009, and a further 18 in 2010, with 9 remaining as controls. In the first year of implementation, SMC was delivered to children aged 3-59 months; the age range was then extended for the latter two years of the study to include children up to 10 years of age. Cluster sample surveys at the end of each transmission season were done to measure coverage of SMC and the prevalence of parasitaemia and anaemia, to monitor molecular markers of drug resistance, and to measure insecticide-treated net (ITN) use. Entomological monitoring and assessment of costs of delivery in each health post and of community attitudes to SMC were also undertaken. About 780,000 treatments were administered over three years. Coverage exceeded 80% each month. Mortality, the primary endpoint, was similar in SMC and control areas (4.6 and 4.5 per 1000 respectively in children under 5 years and 1.3 and 1.2 per 1000 in children 5-9 years of age; the overall mortality rate ratio [SMC: no SMC] was 0.90, 95% CI 0.68-1.2, p = 0.496). A reduction of 60% (95% CI 54%-64%, p < 0.001) in the incidence of malaria cases confirmed by a rapid diagnostic test (RDT) and a reduction of 69% (95% CI 65%-72%, p < 0.001) in the number of treatments for malaria (confirmed and unconfirmed) was observed in children. In areas where SMC was implemented, incidence of confirmed malaria in adults and in children too old to receive SMC was reduced by 26% (95% CI 18%-33%, p < 0.001) and the total number of treatments for malaria (confirmed and unconfirmed) in these older age groups was reduced by 29% (95% CI 21%-35%, p < 0.001). One hundred and twenty-three children were admitted to hospital with a diagnosis of severe malaria, with 64 in control areas and 59 in SMC areas, showing a reduction in the incidence rate of severe disease of 45% (95% CI 5%-68%, p = 0.031). Estimates of the reduction in the prevalence of parasitaemia at the end of the transmission season in SMC areas were 68% (95% CI 35%-85%) p = 0.002 in 2008, 84% (95% CI 58%-94%, p < 0.001) in 2009, and 30% (95% CI -130%-79%, p = 0.56) in 2010. SMC was well tolerated with no serious adverse reactions attributable to SMC drugs. Vomiting was the most commonly reported mild adverse event but was reported in less than 1% of treatments. The average cost of delivery was US$0.50 per child per month, but varied widely depending on the size of the health post. Limitations included the low rate of mortality, which limited our ability to detect an effect on this endpoint. CONCLUSIONS SMC substantially reduced the incidence of outpatient cases of malaria and of severe malaria in children, but no difference in all-cause mortality was observed. Introduction of SMC was associated with an overall reduction in malaria incidence in untreated age groups. In many areas of Africa with seasonal malaria, there is a substantial burden in older children that could be prevented by SMC. SMC in older children is well tolerated and effective and can contribute to reducing malaria transmission. TRIAL REGISTRATION ClinicalTrials.gov NCT00712374.
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Affiliation(s)
- Badara Cissé
- Université Cheikh Anta Diop, Dakar, Sénégal
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - El Hadj Ba
- London School of Hygiene & Tropical Medicine, London, United Kingdom
- Institut de Recherche pour le Développement, Dakar, Sénégal
| | - Cheikh Sokhna
- Institut de Recherche pour le Développement, Dakar, Sénégal
| | | | | | | | - Catherine Pitt
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - Matthew Cairns
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | - Aminata Lo
- Université Cheikh Anta Diop, Dakar, Sénégal
| | - Roger Tine
- Université Cheikh Anta Diop, Dakar, Sénégal
| | | | | | - Ousmane Sy
- Université Cheikh Anta Diop, Dakar, Sénégal
| | | | | | - Clare Flach
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | - Colin Sutherland
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | | | - Brian Greenwood
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Oumar Gaye
- Université Cheikh Anta Diop, Dakar, Sénégal
| | - Paul Milligan
- London School of Hygiene & Tropical Medicine, London, United Kingdom
- * E-mail:
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Thiam S, Ndiaye JL, Diallo I, Gatonga P, Fall FB, Diallo NE, Faye B, Diouf ML, Ndiop M, Diouf MB, Gaye O, Thior M. Safety monitoring of artemisinin combination therapy through a national pharmacovigilance system in an endemic malaria setting. Malar J 2013; 12:54. [PMID: 23384036 PMCID: PMC3598537 DOI: 10.1186/1475-2875-12-54] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 01/17/2013] [Indexed: 12/03/2022] Open
Abstract
Background The National Malaria Control Programme in Senegal, introduced since 2006, artemisinin-based combination therapy (ACT administration) for the treatment of uncomplicated malaria cases. In this framework, an anti-malarial pharmacovigilance plan was developed and implemented in all public health services. This study investigated the occurrence of Adverse Drug Events (ADEs) after ACT. Methods The study was conducted between January 2007 and December 2009. It was based on spontaneous reports of ADEs in public health facilities. Data on patient demographic characteristics, dispensing facility, adverse signs and symptoms and causality were collected from a total of 123 patients. Results The age range of these patients was six months to 93 years with a mean of 25.9 years. Of the reported symptoms, 46.7% were related to the abdomen and the digestive system. Symptoms related to the nervous system, skin and subcutaneous tissue, circulatory and respiratory systems and general symptoms and signs were 7%, 9.7%, 3.5% and 31.3%, respectively. Causality results linked 14.3% of symptoms to Falcimon® (Artesunate-Amodiaquine) with certainty. Effects were classified as mild and severe in 69.1% and 7.3% of cases respectively while 23.6% were serious. All patients with serious ADEs were hospitalized. One death was reported in a patient who had taken 24 pills at once. Conclusion These results confirm the need to develop and implement pharmacovigilance systems in malaria endemic countries in order to monitor the safety of anti-malarial treatments.
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Affiliation(s)
- Sylla Thiam
- African Medical and Research Foundation, Nairobi, Kenya.
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Thiam S, Thior M, Faye B, Ndiop M, Diouf ML, Diouf MB, Diallo I, Fall FB, Ndiaye JL, Albertini A, Lee E, Jorgensen P, Gaye O, Bell D. Major reduction in anti-malarial drug consumption in Senegal after nation-wide introduction of malaria rapid diagnostic tests. PLoS One 2011; 6:e18419. [PMID: 21494674 PMCID: PMC3071817 DOI: 10.1371/journal.pone.0018419] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Accepted: 03/05/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND While WHO recently recommended universal parasitological confirmation of suspected malaria prior to treatment, debate has continued as to whether wide-scale use of rapid diagnostic tests (RDTs) can achieve this goal. Adherence of health service personnel to RDT results has been poor in some settings, with little impact on anti-malarial drug consumption. The Senegal national malaria control programme introduced universal parasite-based diagnosis using malaria RDTs from late 2007 in all public health facilities. This paper assesses the impact of this programme on anti-malarial drug consumption and disease reporting. METHODS AND FINDINGS Nationally-collated programme data from 2007 to 2009 including malaria diagnostic outcomes, prescription of artemisinin-based combination therapy (ACT) and consumption of RDTs in public health facilities, were reviewed and compared. Against a marked seasonal variation in all-cause out-patient visits, non-malarial fever and confirmed malaria, parasite-based diagnosis increased nationally from 3.9% of reported malaria-like febrile illness to 86.0% over a 3 year period. The prescription of ACT dropped throughout this period from 72.9% of malaria-like febrile illness to 31.5%, reaching close equivalence to confirmed malaria (29.9% of 584,873 suspect fever cases). An estimated 516,576 courses of inappropriate ACT prescription were averted. CONCLUSIONS The data indicate high adherence of anti-malarial prescribing practice to RDT results after an initial run-in period. The large reduction in ACT consumption enabled by the move from symptom-based to parasite-based diagnosis demonstrates that effective roll-out and use of malaria RDTs is achievable on a national scale through well planned and structured implementation. While more detailed information on management of parasite-negative cases is required at point of care level to assess overall cost-benefits to the health sector, considerable cost-savings were achieved in ACT procurement. Programmes need to be allowed flexibility in management of these funds to address increases in other programmatic costs that may accrue from improved diagnosis of febrile disease.
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Affiliation(s)
- Sylla Thiam
- Programme National de lutte contre le
Paludisme, Ministère de la Santé, Dakar Fann, Senegal
| | - Moussa Thior
- Programme National de lutte contre le
Paludisme, Ministère de la Santé, Dakar Fann, Senegal
| | - Babacar Faye
- Faculté de Médecine,
Université Cheikh Anta Diop de Dakar, Fann Dakar,
Sénégal
| | - Médoune Ndiop
- Programme National de lutte contre le
Paludisme, Ministère de la Santé, Dakar Fann, Senegal
| | - Mamadou Lamine Diouf
- Programme National de lutte contre le
Paludisme, Ministère de la Santé, Dakar Fann, Senegal
| | - Mame Birame Diouf
- Programme National de lutte contre le
Paludisme, Ministère de la Santé, Dakar Fann, Senegal
| | - Ibrahima Diallo
- Programme National de lutte contre le
Paludisme, Ministère de la Santé, Dakar Fann, Senegal
| | - Fatou Ba Fall
- Programme National de lutte contre le
Paludisme, Ministère de la Santé, Dakar Fann, Senegal
| | - Jean Louis Ndiaye
- Faculté de Médecine,
Université Cheikh Anta Diop de Dakar, Fann Dakar,
Sénégal
| | - Audrey Albertini
- Foundation for Innovative New Diagnostics
(FIND), Geneva, Switzerland
| | - Evan Lee
- Foundation for Innovative New Diagnostics
(FIND), Geneva, Switzerland
| | | | - Oumar Gaye
- Faculté de Médecine,
Université Cheikh Anta Diop de Dakar, Fann Dakar,
Sénégal
| | - David Bell
- Global Malaria Programme, World Health
Organization, Geneva, Switzerland
- * E-mail:
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