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Abdel Hamid MM, Abdelraheem MH, Acheampong DO, Ahouidi A, Ali M, Almagro-Garcia J, Amambua-Ngwa A, Amaratunga C, Amenga-Etego L, Andagalu B, Anderson T, Andrianaranjaka V, Aniebo I, Aninagyei E, Ansah F, Ansah PO, Apinjoh T, Arnaldo P, Ashley E, Auburn S, Awandare GA, Ba H, Baraka V, Barry A, Bejon P, Bertin GI, Boni MF, Borrmann S, Bousema T, Bouyou-Akotet M, Branch O, Bull PC, Cheah H, Chindavongsa K, Chookajorn T, Chotivanich K, Claessens A, Conway DJ, Corredor V, Courtier E, Craig A, D'Alessandro U, Dama S, Day N, Denis B, Dhorda M, Diakite M, Djimde A, Dolecek C, Dondorp A, Doumbia S, Drakeley C, Drury E, Duffy P, Echeverry DF, Egwang TG, Enosse SMM, Erko B, Fairhurst RM, Faiz A, Fanello CA, Fleharty M, Forbes M, Fukuda M, Gamboa D, Ghansah A, Golassa L, Goncalves S, Harrison GLA, Healy SA, Hendry JA, Hernandez-Koutoucheva A, Hien TT, Hill CA, Hombhanje F, Hott A, Htut Y, Hussein M, Imwong M, Ishengoma D, Jackson SA, Jacob CG, Jeans J, Johnson KJ, Kamaliddin C, Kamau E, Keatley J, Kochakarn T, Konate DS, Konaté A, Kone A, Kwiatkowski DP, Kyaw MP, Kyle D, Lawniczak M, Lee SK, Lemnge M, Lim P, Lon C, Loua KM, Mandara CI, Marfurt J, Marsh K, Maude RJ, Mayxay M, Maïga-Ascofaré O, Miotto O, Mita T, Mobegi V, Mohamed AO, Mokuolu OA, Montgomery J, Morang’a CM, Mueller I, Murie K, Newton PN, Ngo Duc T, Nguyen T, Nguyen TN, Nguyen Thi Kim T, Nguyen Van H, Noedl H, Nosten F, Noviyanti R, Ntui VNN, Nzila A, Ochola-Oyier LI, Ocholla H, Oduro A, Omedo I, Onyamboko MA, Ouedraogo JB, Oyebola K, Oyibo WA, Pearson R, Peshu N, Phyo AP, Plowe CV, Price RN, Pukrittayakamee S, Quang HH, Randrianarivelojosia M, Rayner JC, Ringwald P, Rosanas-Urgell A, Rovira-Vallbona E, Ruano-Rubio V, Ruiz L, Saunders D, Shayo A, Siba P, Simpson VJ, Sissoko MS, Smith C, Su XZ, Sutherland C, Takala-Harrison S, Talman A, Tavul L, Thanh NV, Thathy V, Thu AM, Toure M, Tshefu A, Verra F, Vinetz J, Wellems TE, Wendler J, White NJ, Whitton G, Yavo W, van der Pluijm RW. Pf7: an open dataset of Plasmodium falciparum genome variation in 20,000 worldwide samples. Wellcome Open Res 2023; 8:22. [PMID: 36864926 PMCID: PMC9971654 DOI: 10.12688/wellcomeopenres.18681.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2022] [Indexed: 01/18/2023] Open
Abstract
We describe the MalariaGEN Pf7 data resource, the seventh release of Plasmodium falciparum genome variation data from the MalariaGEN network. It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented. For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations. We identify a large number of newly emerging crt mutations in parts of Southeast Asia, and show examples of heterogeneities in patterns of drug resistance within Africa and within the Indian subcontinent. We describe the profile of variations in the C-terminal of the csp gene and relate this to the sequence used in the RTS,S and R21 malaria vaccines. Pf7 provides high-quality data on genotype calls for 6 million SNPs and short indels, analysis of large deletions that cause failure of rapid diagnostic tests, and systematic characterisation of six major drug resistance loci, all of which can be freely downloaded from the MalariaGEN website.
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Affiliation(s)
| | | | - Mohamed Hassan Abdelraheem
- Institute of Endemic Diseases, University of Khartoum, Khartoum, Sudan
- Nuclear Applications In Biological Sciences, Sudan Atomic Energy Commission, Khartoum, Sudan
| | - Desmond Omane Acheampong
- Department of Biomedical Sciences, School of Allied Health Sciences, University of Cape Coast, Cape Coast, Ghana
| | - Ambroise Ahouidi
- Health Research Epidemiological Surveillance and Training Institute (IRESSEF), Université Cheikh Anta Diop, Dakar, Senegal
| | - Mozam Ali
- Wellcome Sanger Institute, Hinxton, UK
| | | | - Alfred Amambua-Ngwa
- Wellcome Sanger Institute, Hinxton, UK
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Chanaki Amaratunga
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Maryland, USA
| | - Lucas Amenga-Etego
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Legon, Ghana
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | - Ben Andagalu
- United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Tim Anderson
- Texas Biomedical Research Institute, San Antonio, USA
| | | | | | - Enoch Aninagyei
- Department of Biomedical Sciences, School of Basic and Biomedical Sciences, University of Health & Allied Sciences, Ho, Ghana
| | - Felix Ansah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Legon, Ghana
| | - Patrick O Ansah
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | | | - Paulo Arnaldo
- Instituto Nacional de Saúde (INS), Maputo, Mozambique
| | - Elizabeth Ashley
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | - Sarah Auburn
- Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia
- Nuffield Department of Medicine, University of Oxford, UK
| | - Gordon A Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Legon, Ghana
| | - Hampate Ba
- Institut National de Recherche en Santé Publique, Nouakchott, Mauritania
| | - Vito Baraka
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania
- Department of Epidemiology, International Health Unit, Universiteit Antwerpen, Antwerp, Belgium
| | - Alyssa Barry
- Walter and Eliza Hall Institute, Melbourne, Australia
- Deakin University, Geelong, Australia
- Burnet Institute, Melbourne, Australia
| | - Philip Bejon
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Maciej F Boni
- Nuffield Department of Medicine, University of Oxford, UK
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Steffen Borrmann
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Teun Bousema
- London School of Hygiene and Tropical Medicine, London, UK
- Radboud University Medical Center, Nijmegen, The Netherlands
| | - Marielle Bouyou-Akotet
- Department of Parasitology-Mycology, Université des Sciences de la Santé, Libreville, Gabon
| | - Oralee Branch
- NYU School of Medicine Langone Medical Center, New York, USA
| | - Peter C Bull
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - Huch Cheah
- National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia
| | | | | | | | - Antoine Claessens
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
- LPHI, MIVEGEC, INSERM, CNRS, IRD, University of Montpellier, Montpellier, France
| | - David J Conway
- London School of Hygiene and Tropical Medicine, London, UK
| | | | | | - Alister Craig
- Liverpool School of Tropical Medicine, Liverpool, UK
- Malawi-Liverpool-Wellcome Trust Clinical Research Program, Blantyre, Malawi
| | - Umberto D'Alessandro
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Souleymane Dama
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Nicholas Day
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | - Brigitte Denis
- Malawi-Liverpool-Wellcome Trust Clinical Research Program, Blantyre, Malawi
| | - Mehul Dhorda
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
- WorldWide Antimalarial Resistance Network – Asia Regional Centre, Bangkok, Thailand
| | - Mahamadou Diakite
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center (UCRC), Bamako, Mali
| | - Abdoulaye Djimde
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Arjen Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | - Seydou Doumbia
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
- University Clinical Research Center (UCRC), Bamako, Mali
| | - Chris Drakeley
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - Patrick Duffy
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Maryland, USA
| | - Diego F Echeverry
- Departamento de Microbiología, Universidad del Valle, Cali, Colombia
- Centro Internacional de Entrenamiento e Investigaciones Médicas - CIDEIM, Cali, Colombia
| | | | | | - Berhanu Erko
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | | | - Caterina A Fanello
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Mark Fleharty
- Broad Institute of Harvard and MIT and Harvard, Cambridge, MA, USA
| | | | - Mark Fukuda
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Dionicia Gamboa
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Anita Ghansah
- Nogouchi Memorial Institute for Medical Research, Legon-Accra, Ghana
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | | | - Sara Anne Healy
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Maryland, USA
| | - Jason A Hendry
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Tran Tinh Hien
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Catherine A Hill
- Department of Entomology, Purdue University, West Lafayette, USA
| | - Francis Hombhanje
- Centre for Health Research & Diagnostics, Divine Word University, Madang, Papua New Guinea
| | | | - Ye Htut
- Department of Medical Research, Yangon, Myanmar
| | - Mazza Hussein
- Institute of Endemic Diseases, University of Khartoum, Khartoum, Sudan
| | | | - Deus Ishengoma
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania
- East African Consortium for Clinical Research (EACCR), Dar es Salaam, Tanzania
| | - Scott A Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA, USA
| | | | | | | | - Claire Kamaliddin
- Institute of Research for Development (IRD), Paris, France
- The University of Calgary, Calgary, Canada
| | - Edwin Kamau
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | | | | | - Drissa S Konate
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Aminatou Kone
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Myat P Kyaw
- Myanmar Oxford Clinical Research Unit, University of Oxford, Yangon, Myanmar
- University of Public Health, Yangon, Myanmar
| | - Dennis Kyle
- University of South Florida, Tampa, USA
- University of Georgia, Athens, USA
| | | | - Samuel K Lee
- Broad Institute of Harvard and MIT and Harvard, Cambridge, MA, USA
| | - Martha Lemnge
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania
| | - Pharath Lim
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Maryland, USA
- Medical Care Development International, Maryland, USA
| | - Chanthap Lon
- National Institute of Allergy and Infectious Diseases, Phnom Penh, Cambodia
| | - Kovana M Loua
- University Gamal Abdel Nasser of Conakry, Conakry, Guinea
- Institut National de Santé Publique, Conakry, Guinea
| | - Celine I Mandara
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania
| | - Jutta Marfurt
- Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia
| | - Kevin Marsh
- Nuffield Department of Medicine, University of Oxford, UK
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Richard James Maude
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
- Harvard TH Chan School of Public Health, Harvard University, Boston, USA
| | - Mayfong Mayxay
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
- Institute of Research and Education Development (IRED), University of Health Sciences, Ministry of Health, Vientiane, Lao People's Democratic Republic
| | - Oumou Maïga-Ascofaré
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- Research in Tropical Medicine, Kwame Nkrumah University of Sciences and Technology, Kumasi, Ghana
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, UK
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
- MRC Centre for Genomics and Global Health, Big Data Institute, Oxford University, Oxford, UK
| | | | - Victor Mobegi
- Department of Biochemistry and Centre for Biotechnology and Bioinformatics, University of Nairobi, Nairobi, Kenya
| | | | - Olugbenga A Mokuolu
- Department of Paediatrics and Child Health, University of Ilorin, Ilorin, Nigeria
| | - Jaqui Montgomery
- Malawi-Liverpool-Wellcome Trust Clinical Research Program, Blantyre, Malawi
- World Mosquito Program, Monash University, Melbourne, Australia
| | - Collins Misita Morang’a
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Legon, Ghana
| | - Ivo Mueller
- Walter and Eliza Hall Institute, Melbourne, Australia
- University of Melbourne, Melbourne, Australia
| | | | - Paul N Newton
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Thang Ngo Duc
- National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
| | | | - Thuy-Nhien Nguyen
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | | | - Hong Nguyen Van
- National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
| | - Harald Noedl
- MARIB - Malaria Research Initiative Bandarban, Bandarban, Bangladesh
- Medical University of Vienna, Vienna, Austria
| | - Francois Nosten
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
| | | | | | - Alexis Nzila
- King Fahid University of Petroleum and Minerals (KFUMP), Dhahran, Saudi Arabia
| | | | - Harold Ocholla
- KEMRI Centres for Disease Control and Prevention (CDC) Research Program, Kisumu, Kenya
- Centre for Bioinformatics and Biotechnology, University of Nairobi, Nairobi, Kenya
| | - Abraham Oduro
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | - Irene Omedo
- Wellcome Sanger Institute, Hinxton, UK
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Marie A Onyamboko
- Kinshasa School of Public Health, University of Kinshasa, Kinshasa, Congo, Democratic Republic
| | | | - Kolapo Oyebola
- Nigerian Institute of Medical Research, Lagos, Nigeria
- Parasitology and Bioinformatics Unit, Faculty of Science, University of Lagos, Lagos, Nigeria
| | | | | | - Norbert Peshu
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Aung P Phyo
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
- Shoklo Malaria Research Unit, Bangkok, Thailand
| | | | - Ric N Price
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
- Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia
| | | | - Huynh Hong Quang
- Institute of Malariology, Parasitology, and Entomology (IMPE) Quy Nhon, Ministry of Health, Quy Nhon, Vietnam
| | - Milijaona Randrianarivelojosia
- Institut Pasteur de Madagascar, Antananarivo, Madagascar
- Universités d'Antananarivo et de Mahajanga, Antananarivo, Madagascar
| | - Julian C Rayner
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | | | | | | | | | - Lastenia Ruiz
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | - David Saunders
- Department of Medicine, Uniformed Services University, Bethesda, MD, USA
| | - Alex Shayo
- Nelson Mandela Institute of Science and Technology, Arusha, Tanzania
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | | | - Mahamadou S. Sissoko
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Xin-zhuan Su
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Maryland, USA
| | | | - Shannon Takala-Harrison
- Center for Vaccine Development and Global Health, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Arthur Talman
- MIVEGEC, Université de Montpellier, IRD, CNRS, Montpellier, France
| | - Livingstone Tavul
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Ngo Viet Thanh
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Vandana Thathy
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Aung Myint Thu
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
| | - Mahamoudou Toure
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | | | - Joseph Vinetz
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
- Yale School of Medicine, New Haven, CT, USA
| | - Thomas E Wellems
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Maryland, USA
| | - Jason Wendler
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Maryland, USA
- Seattle Children’s Hospital, Seattle, USA
| | - Nicholas J White
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | - William Yavo
- University Félix Houphouët-Boigny, Abidjan, Cote d'Ivoire
- Malaria Research and Control Center of the National Institute of Public Health, Abidjan, Cote d'Ivoire
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Omedo I, Bartilol B, Kimani D, Gonçalves S, Drury E, Rono MK, Abdi AI, Almagro-Garcia J, Amato R, Pearson RD, Ochola-Oyier LI, Kwiatkowski D, Bejon P. Spatio-temporal distribution of antimalarial drug resistant gene mutations in a Plasmodium falciparum parasite population from Kilifi, Kenya: A 25-year retrospective study. Wellcome Open Res 2022. [DOI: 10.12688/wellcomeopenres.17656.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [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: Antimalarial drug resistance is a major obstacle to sustainable malaria control. Here we use amplicon sequencing to describe molecular markers of drug resistance in Plasmodium falciparum parasites from Kilifi county in the coastal region of Kenya over a 25-year period. Methods: We performed P. falciparum amplicon sequencing on 1162 malaria-infected blood samples collected between 1994 and 2018 to identify markers of antimalarial drug resistance in the Pfcrt, Pfdhfr, Pfdhps, Pfmdr1, Pfexo, Pfkelch13, plasmepsin 2/3, Pfarps10, Pffd, and Pfmdr2 genes. We further interrogated parasite population structure using a genetic barcode of 101 drug resistance-unrelated single nucleotide polymorphisms (SNPs) distributed across the genomes of 1245 P. falciparum parasites. Results: Two major changes occurred in the parasite population over the 25 years studied. In 1994, approximately 75% of parasites carried the marker of chloroquine resistance, CVIET. This increased to 100% in 1999 and then declined steadily, reaching 6.7% in 2018. Conversely, the quintuple mutation form of sulfadoxine-pyrimethamine resistance increased from 16.7% in 1994 to 83.6% in 2018. Several non-synonymous mutations were identified in the Kelch13 gene, although none of them are currently associated with artemisinin resistance. We observed a temporal increase in the Pfmdr1 NFD haplotype associated with lumefantrine resistance, but observed no evidence of piperaquine resistance. SNPs in other parts of the genome showed no significant temporal changes despite the marked changes in drug resistance loci over this period. Conclusions: We identified substantial changes in molecular markers of P. falciparum drug resistance over 25 years in coastal Kenya, but no associated changes in the parasite population structure.
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Ahouidi A, Ali M, Almagro-Garcia J, Amambua-Ngwa A, Amaratunga C, Amato R, Amenga-Etego L, Andagalu B, Anderson TJC, Andrianaranjaka V, Apinjoh T, Ariani C, Ashley EA, Auburn S, Awandare GA, Ba H, Baraka V, Barry AE, Bejon P, Bertin GI, Boni MF, Borrmann S, Bousema T, Branch O, Bull PC, Busby GBJ, Chookajorn T, Chotivanich K, Claessens A, Conway D, Craig A, D'Alessandro U, Dama S, Day NPJ, Denis B, Diakite M, Djimdé A, Dolecek C, Dondorp AM, Drakeley C, Drury E, Duffy P, Echeverry DF, Egwang TG, Erko B, Fairhurst RM, Faiz A, Fanello CA, Fukuda MM, Gamboa D, Ghansah A, Golassa L, Goncalves S, Hamilton WL, Harrison GLA, Hart L, Henrichs C, Hien TT, Hill CA, Hodgson A, Hubbart C, Imwong M, Ishengoma DS, Jackson SA, Jacob CG, Jeffery B, Jeffreys AE, Johnson KJ, Jyothi D, Kamaliddin C, Kamau E, Kekre M, Kluczynski K, Kochakarn T, Konaté A, Kwiatkowski DP, Kyaw MP, Lim P, Lon C, Loua KM, Maïga-Ascofaré O, Malangone C, Manske M, Marfurt J, Marsh K, Mayxay M, Miles A, Miotto O, Mobegi V, Mokuolu OA, Montgomery J, Mueller I, Newton PN, Nguyen T, Nguyen TN, Noedl H, Nosten F, Noviyanti R, Nzila A, Ochola-Oyier LI, Ocholla H, Oduro A, Omedo I, Onyamboko MA, Ouedraogo JB, Oyebola K, Pearson RD, Peshu N, Phyo AP, Plowe CV, Price RN, Pukrittayakamee S, Randrianarivelojosia M, Rayner JC, Ringwald P, Rockett KA, Rowlands K, Ruiz L, Saunders D, Shayo A, Siba P, Simpson VJ, Stalker J, Su XZ, Sutherland C, Takala-Harrison S, Tavul L, Thathy V, Tshefu A, Verra F, Vinetz J, Wellems TE, Wendler J, White NJ, Wright I, Yavo W, Ye H. An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples. Wellcome Open Res 2021; 6:42. [PMID: 33824913 PMCID: PMC8008441 DOI: 10.12688/wellcomeopenres.16168.1] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/15/2021] [Indexed: 02/02/2023] Open
Abstract
MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.
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Affiliation(s)
| | | | - Mozam Ali
- Wellcome Sanger Institute, Hinxton, UK
| | - Jacob Almagro-Garcia
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Alfred Amambua-Ngwa
- Wellcome Sanger Institute, Hinxton, UK,Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Chanaki Amaratunga
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Roberto Amato
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Lucas Amenga-Etego
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana,West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana
| | - Ben Andagalu
- United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | | | | | | | | | - Elizabeth A Ashley
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Sarah Auburn
- Menzies School of Health Research, Darwin, Australia,Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Gordon A. Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana,University of Ghana, Legon, Ghana
| | - Hampate Ba
- Institut National de Recherche en Santé Publique, Nouakchott, Mauritania
| | - Vito Baraka
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,Department of Epidemiology, International Health Unit, University of Antwerp, Antwerp, Belgium
| | - Alyssa E. Barry
- Deakin University, Geelong, Australia,Burnet Institute, Melbourne, Australia,Walter and Eliza Hall Institute, Melbourne, Australia
| | - Philip Bejon
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Maciej F. Boni
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Steffen Borrmann
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Teun Bousema
- London School of Hygiene and Tropical Medicine, London, UK,Radboud University Medical Center, Nijmegen, The Netherlands
| | - Oralee Branch
- NYU School of Medicine Langone Medical Center, New York, USA
| | - Peter C. Bull
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Pathology, University of Cambridge, Cambridge, UK
| | - George B. J. Busby
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Antoine Claessens
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia,LPHI, MIVEGEC, INSERM, CNRS, IRD, University of Montpellier, Montpellier, France
| | - David Conway
- London School of Hygiene and Tropical Medicine, London, UK
| | - Alister Craig
- Liverpool School of Tropical Medicine, Liverpool, UK,Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Umberto D'Alessandro
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Souleymane Dama
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Nicholas PJ Day
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Brigitte Denis
- Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Mahamadou Diakite
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Abdoulaye Djimdé
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Chris Drakeley
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - Patrick Duffy
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Diego F. Echeverry
- Centro Internacional de Entrenamiento e Investigaciones Médicas - CIDEIM, Cali, Colombia,Universidad Icesi, Cali, Colombia
| | | | - Berhanu Erko
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | | | | | - Mark M. Fukuda
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Dionicia Gamboa
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Anita Ghansah
- Nogouchi Memorial Institute for Medical Research, Legon-Accra, Ghana
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | - William L. Hamilton
- Wellcome Sanger Institute, Hinxton, UK,Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | | | - Lee Hart
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Christa Henrichs
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Tran Tinh Hien
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | | | - Christina Hubbart
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Deus S. Ishengoma
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,East African Consortium for Clinical Research (EACCR), Dar es Salaam, Tanzania
| | - Scott A. Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA, USA
| | | | - Ben Jeffery
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Anna E. Jeffreys
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Kimberly J. Johnson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Edwin Kamau
- Walter Reed Army Institute of Research, U.S. Military HIV Research Program, Silver Spring, MD, USA
| | | | - Krzysztof Kluczynski
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Theerarat Kochakarn
- Wellcome Sanger Institute, Hinxton, UK,Mahidol University, Bangkok, Thailand
| | | | - Dominic P. Kwiatkowski
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Myat Phone Kyaw
- The Myanmar Oxford Clinical Research Unit, University of Oxford, Yangon, Myanmar,University of Public Health, Yangon, Myanmar
| | - Pharath Lim
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA,Medical Care Development International, Maryland, USA
| | - Chanthap Lon
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | | | - Oumou Maïga-Ascofaré
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,Research in Tropical Medicine, Kwame Nkrumah University of Sciences and Technology, Kumasi, Ghana
| | | | | | - Jutta Marfurt
- Menzies School of Health Research, Darwin, Australia
| | - Kevin Marsh
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,African Academy of Sciences, Nairobi, Kenya
| | - Mayfong Mayxay
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Vientiane, Lao People's Democratic Republic,Institute of Research and Education Development (IRED), University of Health Sciences, Ministry of Health, Vientiane, Lao People's Democratic Republic
| | - Alistair Miles
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Victor Mobegi
- School of Medicine, University of Nairobi, Nairobi, Kenya
| | - Olugbenga A. Mokuolu
- Department of Paediatrics and Child Health, University of Ilorin, Ilorin, Nigeria
| | - Jacqui Montgomery
- Institute of Vector-Borne Disease, Monash University, Clayton, Victoria, 3800, Australia
| | - Ivo Mueller
- Walter and Eliza Hall Institute, Melbourne, Australia,Barcelona Centre for International Health Research, Barcelona, Spain
| | - Paul N. Newton
- Wellcome Trust-Mahosot Hospital-Oxford Tropical Medicine Research Collaboration, Vientiane, Lao People's Democratic Republic
| | | | - Thuy-Nhien Nguyen
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Harald Noedl
- MARIB - Malaria Research Initiative Bandarban, Bandarban, Bangladesh
| | - Francois Nosten
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Shoklo Malaria Research Unit, Bangkok, Thailand
| | | | - Alexis Nzila
- King Fahid University of Petroleum and Minerals (KFUMP), Dharhran, Saudi Arabia
| | | | - Harold Ocholla
- KEMRI - Centres for Disease Control and Prevention (CDC) Research Program, Kisumu, Kenya,Centre for Bioinformatics and Biotechnology, University of Nairobi, Nairobi, Kenya
| | - Abraham Oduro
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | - Irene Omedo
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Marie A. Onyamboko
- Kinshasa School of Public Health, University of Kinshasa, Kinshasa, Congo, Democratic Republic
| | | | - Kolapo Oyebola
- Nigerian Institute of Medical Research, Lagos, Nigeria,Parasitology and Bioinformatics Unit, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Richard D. Pearson
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Norbert Peshu
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Aung Pyae Phyo
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Shoklo Malaria Research Unit, Bangkok, Thailand
| | - Chris V. Plowe
- School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Ric N. Price
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Menzies School of Health Research, Darwin, Australia,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | - Milijaona Randrianarivelojosia
- Institut Pasteur de Madagascar, Antananarivo, Madagascar,Universités d'Antananarivo et de Mahajanga, Antananarivo, Madagascar
| | | | | | - Kirk A. Rockett
- Wellcome Sanger Institute, Hinxton, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Lastenia Ruiz
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | - David Saunders
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Alex Shayo
- Nelson Mandela Institute of Science and Technology, Arusha, Tanzania
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Victoria J. Simpson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | - Xin-zhuan Su
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | | | - Shannon Takala-Harrison
- Center for Vaccine Development and Global Health, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Livingstone Tavul
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Vandana Thathy
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York, USA
| | | | | | - Joseph Vinetz
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru,Yale School of Medicine, New Haven, CT, USA
| | - Thomas E. Wellems
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Jason Wendler
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Nicholas J. White
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Ian Wright
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - William Yavo
- University Félix Houphouët-Boigny, Abidjan, Cote d'Ivoire,Malaria Research and Control Center of the National Institute of Public Health, Abidjan, Cote d'Ivoire
| | - Htut Ye
- Department of Medical Research, Yangon, Myanmar
| |
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4
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Ahouidi A, Ali M, Almagro-Garcia J, Amambua-Ngwa A, Amaratunga C, Amato R, Amenga-Etego L, Andagalu B, Anderson TJC, Andrianaranjaka V, Apinjoh T, Ariani C, Ashley EA, Auburn S, Awandare GA, Ba H, Baraka V, Barry AE, Bejon P, Bertin GI, Boni MF, Borrmann S, Bousema T, Branch O, Bull PC, Busby GBJ, Chookajorn T, Chotivanich K, Claessens A, Conway D, Craig A, D'Alessandro U, Dama S, Day NPJ, Denis B, Diakite M, Djimdé A, Dolecek C, Dondorp AM, Drakeley C, Drury E, Duffy P, Echeverry DF, Egwang TG, Erko B, Fairhurst RM, Faiz A, Fanello CA, Fukuda MM, Gamboa D, Ghansah A, Golassa L, Goncalves S, Hamilton WL, Harrison GLA, Hart L, Henrichs C, Hien TT, Hill CA, Hodgson A, Hubbart C, Imwong M, Ishengoma DS, Jackson SA, Jacob CG, Jeffery B, Jeffreys AE, Johnson KJ, Jyothi D, Kamaliddin C, Kamau E, Kekre M, Kluczynski K, Kochakarn T, Konaté A, Kwiatkowski DP, Kyaw MP, Lim P, Lon C, Loua KM, Maïga-Ascofaré O, Malangone C, Manske M, Marfurt J, Marsh K, Mayxay M, Miles A, Miotto O, Mobegi V, Mokuolu OA, Montgomery J, Mueller I, Newton PN, Nguyen T, Nguyen TN, Noedl H, Nosten F, Noviyanti R, Nzila A, Ochola-Oyier LI, Ocholla H, Oduro A, Omedo I, Onyamboko MA, Ouedraogo JB, Oyebola K, Pearson RD, Peshu N, Phyo AP, Plowe CV, Price RN, Pukrittayakamee S, Randrianarivelojosia M, Rayner JC, Ringwald P, Rockett KA, Rowlands K, Ruiz L, Saunders D, Shayo A, Siba P, Simpson VJ, Stalker J, Su XZ, Sutherland C, Takala-Harrison S, Tavul L, Thathy V, Tshefu A, Verra F, Vinetz J, Wellems TE, Wendler J, White NJ, Wright I, Yavo W, Ye H. An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples. Wellcome Open Res 2021; 6:42. [PMID: 33824913 PMCID: PMC8008441.2 DOI: 10.12688/wellcomeopenres.16168.2] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/28/2021] [Indexed: 02/02/2023] Open
Abstract
MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.
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Affiliation(s)
| | | | - Mozam Ali
- Wellcome Sanger Institute, Hinxton, UK
| | - Jacob Almagro-Garcia
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Alfred Amambua-Ngwa
- Wellcome Sanger Institute, Hinxton, UK,Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Chanaki Amaratunga
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Roberto Amato
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Lucas Amenga-Etego
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana,West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana
| | - Ben Andagalu
- United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | | | | | | | | | - Elizabeth A Ashley
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Sarah Auburn
- Menzies School of Health Research, Darwin, Australia,Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Gordon A. Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana,University of Ghana, Legon, Ghana
| | - Hampate Ba
- Institut National de Recherche en Santé Publique, Nouakchott, Mauritania
| | - Vito Baraka
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,Department of Epidemiology, International Health Unit, University of Antwerp, Antwerp, Belgium
| | - Alyssa E. Barry
- Deakin University, Geelong, Australia,Burnet Institute, Melbourne, Australia,Walter and Eliza Hall Institute, Melbourne, Australia
| | - Philip Bejon
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Maciej F. Boni
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Steffen Borrmann
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Teun Bousema
- London School of Hygiene and Tropical Medicine, London, UK,Radboud University Medical Center, Nijmegen, The Netherlands
| | - Oralee Branch
- NYU School of Medicine Langone Medical Center, New York, USA
| | - Peter C. Bull
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Pathology, University of Cambridge, Cambridge, UK
| | - George B. J. Busby
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Antoine Claessens
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia,LPHI, MIVEGEC, INSERM, CNRS, IRD, University of Montpellier, Montpellier, France
| | - David Conway
- London School of Hygiene and Tropical Medicine, London, UK
| | - Alister Craig
- Liverpool School of Tropical Medicine, Liverpool, UK,Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Umberto D'Alessandro
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Souleymane Dama
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Nicholas PJ Day
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Brigitte Denis
- Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Mahamadou Diakite
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Abdoulaye Djimdé
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Chris Drakeley
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - Patrick Duffy
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Diego F. Echeverry
- Centro Internacional de Entrenamiento e Investigaciones Médicas - CIDEIM, Cali, Colombia,Universidad Icesi, Cali, Colombia
| | | | - Berhanu Erko
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | | | | | - Mark M. Fukuda
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Dionicia Gamboa
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Anita Ghansah
- Nogouchi Memorial Institute for Medical Research, Legon-Accra, Ghana
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | - William L. Hamilton
- Wellcome Sanger Institute, Hinxton, UK,Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | | | - Lee Hart
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Christa Henrichs
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Tran Tinh Hien
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | | | - Christina Hubbart
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Deus S. Ishengoma
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,East African Consortium for Clinical Research (EACCR), Dar es Salaam, Tanzania
| | - Scott A. Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA, USA
| | | | - Ben Jeffery
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Anna E. Jeffreys
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Kimberly J. Johnson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Edwin Kamau
- Walter Reed Army Institute of Research, U.S. Military HIV Research Program, Silver Spring, MD, USA
| | | | - Krzysztof Kluczynski
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Theerarat Kochakarn
- Wellcome Sanger Institute, Hinxton, UK,Mahidol University, Bangkok, Thailand
| | | | - Dominic P. Kwiatkowski
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Myat Phone Kyaw
- The Myanmar Oxford Clinical Research Unit, University of Oxford, Yangon, Myanmar,University of Public Health, Yangon, Myanmar
| | - Pharath Lim
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA,Medical Care Development International, Maryland, USA
| | - Chanthap Lon
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | | | - Oumou Maïga-Ascofaré
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,Research in Tropical Medicine, Kwame Nkrumah University of Sciences and Technology, Kumasi, Ghana
| | | | | | - Jutta Marfurt
- Menzies School of Health Research, Darwin, Australia
| | - Kevin Marsh
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,African Academy of Sciences, Nairobi, Kenya
| | - Mayfong Mayxay
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Vientiane, Lao People's Democratic Republic,Institute of Research and Education Development (IRED), University of Health Sciences, Ministry of Health, Vientiane, Lao People's Democratic Republic
| | - Alistair Miles
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Victor Mobegi
- School of Medicine, University of Nairobi, Nairobi, Kenya
| | - Olugbenga A. Mokuolu
- Department of Paediatrics and Child Health, University of Ilorin, Ilorin, Nigeria
| | - Jacqui Montgomery
- Institute of Vector-Borne Disease, Monash University, Clayton, Victoria, 3800, Australia
| | - Ivo Mueller
- Walter and Eliza Hall Institute, Melbourne, Australia,Barcelona Centre for International Health Research, Barcelona, Spain
| | - Paul N. Newton
- Wellcome Trust-Mahosot Hospital-Oxford Tropical Medicine Research Collaboration, Vientiane, Lao People's Democratic Republic
| | | | - Thuy-Nhien Nguyen
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Harald Noedl
- MARIB - Malaria Research Initiative Bandarban, Bandarban, Bangladesh
| | - Francois Nosten
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Shoklo Malaria Research Unit, Bangkok, Thailand
| | | | - Alexis Nzila
- King Fahid University of Petroleum and Minerals (KFUMP), Dharhran, Saudi Arabia
| | | | - Harold Ocholla
- KEMRI - Centres for Disease Control and Prevention (CDC) Research Program, Kisumu, Kenya,Centre for Bioinformatics and Biotechnology, University of Nairobi, Nairobi, Kenya
| | - Abraham Oduro
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | - Irene Omedo
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Marie A. Onyamboko
- Kinshasa School of Public Health, University of Kinshasa, Kinshasa, Congo, Democratic Republic
| | | | - Kolapo Oyebola
- Nigerian Institute of Medical Research, Lagos, Nigeria,Parasitology and Bioinformatics Unit, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Richard D. Pearson
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Norbert Peshu
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Aung Pyae Phyo
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Shoklo Malaria Research Unit, Bangkok, Thailand
| | - Chris V. Plowe
- School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Ric N. Price
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Menzies School of Health Research, Darwin, Australia,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | - Milijaona Randrianarivelojosia
- Institut Pasteur de Madagascar, Antananarivo, Madagascar,Universités d'Antananarivo et de Mahajanga, Antananarivo, Madagascar
| | | | | | - Kirk A. Rockett
- Wellcome Sanger Institute, Hinxton, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Lastenia Ruiz
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | - David Saunders
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Alex Shayo
- Nelson Mandela Institute of Science and Technology, Arusha, Tanzania
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Victoria J. Simpson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | - Xin-zhuan Su
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | | | - Shannon Takala-Harrison
- Center for Vaccine Development and Global Health, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Livingstone Tavul
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Vandana Thathy
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York, USA
| | | | | | - Joseph Vinetz
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru,Yale School of Medicine, New Haven, CT, USA
| | - Thomas E. Wellems
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Jason Wendler
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Nicholas J. White
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Ian Wright
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - William Yavo
- University Félix Houphouët-Boigny, Abidjan, Cote d'Ivoire,Malaria Research and Control Center of the National Institute of Public Health, Abidjan, Cote d'Ivoire
| | - Htut Ye
- Department of Medical Research, Yangon, Myanmar
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5
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Ndwiga L, Kimenyi KM, Wamae K, Osoti V, Akinyi M, Omedo I, Ishengoma DS, Duah-Quashie N, Andagalu B, Ghansah A, Amambua-Ngwa A, Tukwasibwe S, Tessema SK, Karema C, Djimde AA, Dondorp AM, Raman J, Snow RW, Bejon P, Ochola-Oyier LI. A review of the frequencies of Plasmodium falciparum Kelch 13 artemisinin resistance mutations in Africa. Int J Parasitol Drugs Drug Resist 2021; 16:155-161. [PMID: 34146993 PMCID: PMC8219943 DOI: 10.1016/j.ijpddr.2021.06.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 05/28/2021] [Accepted: 06/07/2021] [Indexed: 12/23/2022]
Abstract
Artemisinin resistance (AR) emerged in South East Asia 13 years ago and the identification of the resistance conferring molecular marker, Plasmodium falciparum Kelch 13 (Pfk13), 7 years ago has provided an invaluable tool for monitoring AR in malaria endemic countries. Molecular Pfk13 surveillance revealed the resistance foci in the Greater Mekong Subregion, an independent emergence in Guyana, South America, and a low frequency of mutations in Africa. The recent identification of the R561H Pfk13 AR associated mutation in Tanzania, Uganda and in Rwanda, where it has been associated with delayed parasite clearance, should be a concern for the continent. In this review, we provide a summary of Pfk13 resistance associated propeller domain mutation frequencies across Africa from 2012 to 2020, to examine how many other countries have identified these mutations. Only four African countries reported a recent identification of the M476I, P553L, R561H, P574L, C580Y and A675V Pfk13 mutations at low frequencies and with no reports of clinical treatment failure, except for Rwanda. These mutations present a threat to malaria control across the continent, since the greatest burden of malaria remains in Africa. A rise in the frequency of these mutations and their spread would reverse the gains made in the reduction of malaria over the last 20 years, given the lack of new antimalarial treatments in the event artemisinin-based combination therapies fail. The review highlights the frequency of Pfk13 propeller domain mutations across Africa, providing an up-to-date perspective of Pfk13 mutations, and appeals for an urgent and concerted effort to monitoring antimalarial resistance markers in Africa and the efficacy of antimalarials by re-establishing sentinel surveillance systems.
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Affiliation(s)
- Leonard Ndwiga
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya
| | - Kelvin M Kimenyi
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya; Centre for Biotechnology and Bioinformatics, University of Nairobi, Nairobi, Kenya
| | - Kevin Wamae
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya
| | - Victor Osoti
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya
| | - Mercy Akinyi
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya; Institute of Primate Research, National Museums of Kenya, Nairobi, Kenya
| | - Irene Omedo
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya; Big Data Institute at the Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, United Kingdom
| | - Deus S Ishengoma
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania
| | - Nancy Duah-Quashie
- Department of Epidemiology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Ben Andagalu
- United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Anita Ghansah
- Department of Parasitology, Noguchi Memorial Institute for Medical Research (NMIMR), Accra, Ghana
| | | | | | | | - Corine Karema
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; Quality and Equity Healthcare, Kigali, Rwanda
| | - Abdoulaye A Djimde
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Arjen M Dondorp
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom; Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Jaishree Raman
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Disease, Sandringham, Gauteng, South Africa; Wits Research Institute for Malaria, Univerisity of Witwatersrand, Johannesburg, South Africa
| | - Robert W Snow
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Philip Bejon
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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6
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Bartilol B, Omedo I, Mbogo C, Mwangangi J, Rono MK. Bionomics and ecology of Anopheles merus along the East and Southern Africa coast. Parasit Vectors 2021; 14:84. [PMID: 33509262 PMCID: PMC7842043 DOI: 10.1186/s13071-021-04582-z] [Citation(s) in RCA: 6] [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: 09/03/2020] [Accepted: 01/05/2021] [Indexed: 11/25/2022] Open
Abstract
Malaria transmission persists despite the scale-up of interventions such as long-lasting insecticide-treated nets (LLINs) and indoor residual spraying (IRS). Understanding the entomological drivers of transmission is key for the design of effective and sustainable tools to address the challenge. Recent research findings indicate a shift in vector populations from the notorious Anopheles gambiae (s.s.) as a dominant vector to other species as one of the factors contributing to the persistence of malaria transmission. However, there are gaps in the literature regarding the minor vector species which are increasingly taking a lead role in malaria transmission. Currently, minor malaria vectors have behavioural plasticity, which allows their evasion of vector control tools currently in use. To address this, we have reviewed the role of Anopheles merus, a saltwater mosquito species that is becoming an important vector of malaria transmission along the East and Southern African coast. We performed a literature review from PubMed and Google Scholar and reviewed over 50 publications relating to An. merus's bionomics, taxonomy, spatial-temporal distribution and role in malaria transmission. We found that An. merus is an important vector of malaria and that it contributes to residual malaria transmission because of its exophilic tendencies, insecticide resistance and densities that peak during the dry seasons as the freshwater mosquitoes decline. Spatial and temporal studies have also shown that this species has increased its geographical range, densities and vectorial capacity over time. In this review, we highlight the resting behaviour and breeding habitats of this mosquito, which could be targeted for surveillance studies and control interventions. ![]()
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Affiliation(s)
- Brian Bartilol
- Kenya Medical Research Institute, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya. .,Pwani University Bioscience Research Centre (PUBReC), Pwani University, Kilifi, Kenya.
| | - Irene Omedo
- Kenya Medical Research Institute, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Big Data Institute, University of Oxford, Oxford, UK
| | - Charles Mbogo
- Kenya Medical Research Institute, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Joseph Mwangangi
- Kenya Medical Research Institute, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Kenya Medical Research Institute, Centre for Vector Disease Control, Kwale, Kenya
| | - Martin K Rono
- Kenya Medical Research Institute, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya. .,Pwani University Bioscience Research Centre (PUBReC), Pwani University, Kilifi, Kenya.
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7
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Watson OJ, Okell LC, Hellewell J, Slater HC, Unwin HJT, Omedo I, Bejon P, Snow RW, Noor AM, Rockett K, Hubbart C, Nankabirwa JI, Greenhouse B, Chang HH, Ghani AC, Verity R. Evaluating the Performance of Malaria Genetics for Inferring Changes in Transmission Intensity Using Transmission Modeling. Mol Biol Evol 2021; 38:274-289. [PMID: 32898225 PMCID: PMC7783189 DOI: 10.1093/molbev/msaa225] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Substantial progress has been made globally to control malaria, however there is a growing need for innovative new tools to ensure continued progress. One approach is to harness genetic sequencing and accompanying methodological approaches as have been used in the control of other infectious diseases. However, to utilize these methodologies for malaria, we first need to extend the methods to capture the complex interactions between parasites, human and vector hosts, and environment, which all impact the level of genetic diversity and relatedness of malaria parasites. We develop an individual-based transmission model to simulate malaria parasite genetics parameterized using estimated relationships between complexity of infection and age from five regions in Uganda and Kenya. We predict that cotransmission and superinfection contribute equally to within-host parasite genetic diversity at 11.5% PCR prevalence, above which superinfections dominate. Finally, we characterize the predictive power of six metrics of parasite genetics for detecting changes in transmission intensity, before grouping them in an ensemble statistical model. The model predicted malaria prevalence with a mean absolute error of 0.055. Different assumptions about the availability of sample metadata were considered, with the most accurate predictions of malaria prevalence made when the clinical status and age of sampled individuals is known. Parasite genetics may provide a novel surveillance tool for estimating the prevalence of malaria in areas in which prevalence surveys are not feasible. However, the findings presented here reinforce the need for patient metadata to be recorded and made available within all future attempts to use parasite genetics for surveillance.
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Affiliation(s)
- Oliver J Watson
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Lucy C Okell
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Joel Hellewell
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Hannah C Slater
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - H Juliette T Unwin
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Irene Omedo
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Robert W Snow
- Population Health Unit, Kenya Medical Research Institute—Wellcome Trust Research Programme, Nairobi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | | | - Kirk Rockett
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Christina Hubbart
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Joaniter I Nankabirwa
- Infectious Diseases Research Collaboration, Kampala, Uganda
- Makerere University College of Health Sciences, Kampala, Uganda
| | - Bryan Greenhouse
- Department of Medicine, University of California, San Francisco, San Francisco, CA
| | - Hsiao-Han Chang
- Center for Communicable Disease Dynamics, Harvard TH Chan School of Public Health, Boston, MA
| | - Azra C Ghani
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Robert Verity
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
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8
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Malinga J, Mogeni P, Omedo I, Rockett K, Hubbart C, Jeffreys A, Williams TN, Kwiatkowski D, Bejon P, Ross A. Author Correction: Investigating the drivers of the spatio-temporal patterns of genetic differences between Plasmodium falciparum malaria infections in Kilifi County, Kenya. Sci Rep 2020; 10:22416. [PMID: 33361769 PMCID: PMC7758330 DOI: 10.1038/s41598-020-78848-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Josephine Malinga
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Polycarp Mogeni
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Irene Omedo
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Kirk Rockett
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Christina Hubbart
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Anne Jeffreys
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Thomas N Williams
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya.,Department of Medicine, South Kensington Campus, Imperial College London, London, UK
| | - Dominic Kwiatkowski
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK.,Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, UK
| | - Philip Bejon
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya.,Centre for Tropical Medicine & Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Amanda Ross
- Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
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9
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Malinga J, Mogeni P, Omedo I, Rockett K, Hubbart C, Jeffreys A, Williams TN, Kwiatkowski D, Bejon P, Ross A. Investigating the drivers of the spatio-temporal patterns of genetic differences between Plasmodium falciparum malaria infections in Kilifi County, Kenya. Sci Rep 2019; 9:19018. [PMID: 31836742 PMCID: PMC6911066 DOI: 10.1038/s41598-019-54348-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 11/12/2019] [Indexed: 01/17/2023] Open
Abstract
Knowledge of how malaria infections spread locally is important both for the design of targeted interventions aiming to interrupt malaria transmission and the design of trials to assess the interventions. A previous analysis of 1602 genotyped Plasmodium falciparum parasites in Kilifi, Kenya collected over 12 years found an interaction between time and geographic distance: the mean number of single nucleotide polymorphism (SNP) differences was lower for pairs of infections which were both a shorter time interval and shorter geographic distance apart. We determine whether the empiric pattern could be reproduced by a simple model, and what mean geographic distances between parent and offspring infections and hypotheses about genotype-specific immunity or a limit on the number of infections would be consistent with the data. We developed an individual-based stochastic simulation model of households, people and infections. We parameterized the model for the total number of infections, and population and household density observed in Kilifi. The acquisition of new infections, mutation, recombination, geographic location and clearance were included. We fit the model to the observed numbers of SNP differences between pairs of parasite genotypes. The patterns observed in the empiric data could be reproduced. Although we cannot rule out genotype-specific immunity or a limit on the number of infections per individual, they are not necessary to account for the observed patterns. The mean geographic distance between parent and offspring malaria infections for the base model was 0.4 km (95% CI 0.24, 1.20), for a distribution with 58% of distances shorter than the mean. Very short mean distances did not fit well, but mixtures of distributions were also consistent with the data. For a pathogen which undergoes meiosis in a setting with moderate transmission and a low coverage of infections, analytic methods are limited but an individual-based model can be used with genotyping data to estimate parameter values and investigate hypotheses about underlying processes.
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Affiliation(s)
- Josephine Malinga
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Polycarp Mogeni
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Irene Omedo
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Kirk Rockett
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Christina Hubbart
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Anne Jeffreys
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Thomas N Williams
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya.,Department of Medicine, South Kensington Campus, Imperial College London, London, UK
| | - Dominic Kwiatkowski
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK.,Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, UK
| | - Philip Bejon
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya.,Centre for Tropical Medicine & Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Amanda Ross
- Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
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10
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Ochola-Oyier LI, Wamae K, Omedo I, Ogola C, Matharu A, Musabyimana JP, Njogu FK, Marsh K. Few Plasmodium falciparum merozoite ligand and erythrocyte receptor pairs show evidence of balancing selection. Infect Genet Evol 2019; 69:235-245. [PMID: 30735814 PMCID: PMC6403450 DOI: 10.1016/j.meegid.2019.02.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 01/16/2019] [Accepted: 02/04/2019] [Indexed: 01/06/2023]
Abstract
Erythrocyte surface proteins have been identified as receptors of Plasmodium falciparum merozoite proteins. The ligand-receptor interactions enable the parasite to invade human erythrocytes, initiating the clinical symptoms of malaria. These interactions are likely to have had an evolutionary impact on the genes that encode the ligand and receptor proteins. We used sequence data from Kilifi, Kenya to detect departures from neutrality in a paired analysis of P. falciparum merozoite ligands and their erythrocyte receptor genes from the same population. We genotyped parasite and human DNA obtained from 93 individuals with severe malaria. We examined six merozoite ligands EBA175, EBL1, EBA140, MSP1, Rh4 and Rh5, and their corresponding erythrocyte receptors, glycophorin (Gyp) A, GypB, GypC, band 3, complement receptor (CR) 1 and basigin, focusing on the regions involved in the ligand-receptor interactions. Positive Tajima's D values (>1) were observed only in the MSP1 C-terminal region and EBA175 region II, while negative values (<-1) were observed in EBL-1 region II, Rh4, basigin exons 3 and 5, CR1 exon 5, Gyp B exons 2, 3 and 4 and Gyp C exon 2. Additionally, ebl-1 region II and basigin exon 3 showed extreme negative values in all three tests, Tajima's D, Fu & Li D* and F*, ≤ - 2. A large majority of the erythrocyte receptor and merozoite genes have a negative Tajima's D even when compared with previously published whole genome data. Thus, highlighting EBA175 region II and MSP1-33, as outlier genes with a positive Tajima's D (>1). Both these genes contain multiple polymorphisms, which in the case of EBA175 may counteract receptor polymorphisms and/or evade host immune responses and in MSP1 the polymorphisms may primarily evade host immune responses.
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MESH Headings
- Alleles
- Child
- Child, Preschool
- Erythrocytes/metabolism
- Erythrocytes/parasitology
- Female
- Gene Frequency
- Host-Parasite Interactions
- Humans
- Infant
- Infant, Newborn
- Ligands
- Malaria, Falciparum/genetics
- Malaria, Falciparum/metabolism
- Malaria, Falciparum/parasitology
- Male
- Merozoites/metabolism
- Models, Molecular
- Plasmodium falciparum/classification
- Plasmodium falciparum/physiology
- Polymorphism, Genetic
- Protein Conformation
- Protozoan Proteins/genetics
- Receptors, Cell Surface/chemistry
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/metabolism
- Structure-Activity Relationship
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Affiliation(s)
- Lynette Isabella Ochola-Oyier
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108 Kilifi, Kenya; Centre for Biotechnology and Bioinformatics, College of Biological and Physical Sciences, Chiromo Campus, University of Nairobi, P. O. Box 30197, Nairobi, Kenya.
| | - Kevin Wamae
- Centre for Biotechnology and Bioinformatics, College of Biological and Physical Sciences, Chiromo Campus, University of Nairobi, P. O. Box 30197, Nairobi, Kenya
| | - Irene Omedo
- Centre for Biotechnology and Bioinformatics, College of Biological and Physical Sciences, Chiromo Campus, University of Nairobi, P. O. Box 30197, Nairobi, Kenya
| | - Christabel Ogola
- Centre for Biotechnology and Bioinformatics, College of Biological and Physical Sciences, Chiromo Campus, University of Nairobi, P. O. Box 30197, Nairobi, Kenya
| | - Abneel Matharu
- Centre for Biotechnology and Bioinformatics, College of Biological and Physical Sciences, Chiromo Campus, University of Nairobi, P. O. Box 30197, Nairobi, Kenya
| | - Jean Pierre Musabyimana
- Centre for Biotechnology and Bioinformatics, College of Biological and Physical Sciences, Chiromo Campus, University of Nairobi, P. O. Box 30197, Nairobi, Kenya
| | - Francis K Njogu
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108 Kilifi, Kenya
| | - Kevin Marsh
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108 Kilifi, Kenya
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11
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Kamau A, Mwangangi JM, Rono MK, Mogeni P, Omedo I, Midega J, Scott JAG, Bejon P. Variation in the effectiveness of insecticide treated nets against malaria and outdoor biting by vectors in Kilifi, Kenya. Wellcome Open Res 2019; 2:22. [PMID: 30542660 DOI: 10.12688/wellcomeopenres.11073.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2017] [Indexed: 11/20/2022] Open
Abstract
Background: Insecticide treated nets (ITNs) protect humans against bites from the Anopheles mosquito vectors that transmit malaria, thereby reducing malaria morbidity and mortality. It has been noted that ITN use leads to a switch from indoor to outdoor feeding among these vectors. It might be expected that outdoor feeding would undermine the effectiveness of ITNs that target indoors vectors, but data are limited. Methods: We linked homestead level geospatial data to clinical surveillance data at a primary healthcare facility in Kilifi County in order to map geographical heterogeneity in ITN effectiveness and observed vector feeding behaviour using landing catches and CDC light traps in six selected areas of varying ITN effectiveness. We quantified the interaction between mosquitoes and humans to evaluate whether outdoor vector biting is a potential explanation for the variation in ITN effectiveness. Results: We observed 37% and 46% visits associated with positive malaria slides among ITN users and non-ITN-users, respectively; ITN use was associated with 32% protection from malaria (crude OR = 0.68, 95% CI: 0.64, 0.73). We obtained modification of ITN effectiveness by geographical area (p=0.016), and identified 6 hotspots using the spatial scan statistic. Majority of mosquitoes were caught outdoor (60%) and were of the An. funestus group (75%). The overall propensity to feed at times when most people were asleep was high; the vast majority of the Anopheles mosquitoes were caught at times when most people are indoors asleep. Estimates for the proportion of human-mosquito contact between the first and last hour when most humans were asleep was consistently high across all locations, ranging from 0.83 to 1.00. Conclusion: Our data do not provide evidence of an epidemiological association between microgeographical variations in ITN effectiveness and variations in the microgeographical distribution of outdoor biting.
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Affiliation(s)
- Alice Kamau
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Joseph M Mwangangi
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Integrated Vector and Disease Management Cluster, International Centre of Insect Physiology and Ecology, Nairobi, Kenya.,Pwani University Bioscience Research Centre, Pwani University, Kilifi, Kenya
| | - Martin K Rono
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Pwani University Bioscience Research Centre, Pwani University, Kilifi, Kenya
| | - Polycarp Mogeni
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Irene Omedo
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Janet Midega
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Centre for Genomics and Global Health, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - J Anthony G Scott
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, WC1E 7HT, UK
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, OX3 7FZ, UK
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12
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Kamau A, Mwangangi JM, Rono MK, Mogeni P, Omedo I, Midega J, Scott JAG, Bejon P. Variation in the effectiveness of insecticide treated nets against malaria and outdoor biting by vectors in Kilifi, Kenya. Wellcome Open Res 2018; 2:22. [PMID: 30542660 PMCID: PMC6281023 DOI: 10.12688/wellcomeopenres.11073.4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/27/2018] [Indexed: 12/27/2022] Open
Abstract
Background: Insecticide treated nets (ITNs) protect humans against bites from the
Anopheles mosquito vectors that transmit malaria, thereby reducing malaria morbidity and mortality. It has been noted that ITN use leads to a switch from indoor to outdoor feeding among these vectors. It might be expected that outdoor feeding would undermine the effectiveness of ITNs that target indoors vectors, but data are limited. Methods: We linked homestead level geospatial data to clinical surveillance data at a primary healthcare facility in Kilifi County in order to map geographical heterogeneity in ITN effectiveness and observed vector feeding behaviour using landing catches and CDC light traps in six selected areas of varying ITN effectiveness. We quantified the interaction between mosquitoes and humans to evaluate whether outdoor vector biting is a potential explanation for the variation in ITN effectiveness. Results: We observed 37% and 46% visits associated with positive malaria slides among ITN users and non-ITN-users, respectively; ITN use was associated with 32% protection from malaria (crude OR = 0.68, 95% CI: 0.64, 0.73). We obtained modification of ITN effectiveness by geographical area (p=0.016), and identified 6 hotspots using the spatial scan statistic. Majority of mosquitoes were caught outdoor (60%) and were of the
An. funestus group (75%). The overall propensity to feed at times when most people were asleep was high; the vast majority of the
Anopheles mosquitoes were caught at times when most people are indoors asleep. Estimates for the proportion of human-mosquito contact between the first and last hour when most humans were asleep was consistently high across all locations, ranging from 0.83 to 1.00. Conclusion: Our data do not provide evidence of an epidemiological association between microgeographical variations in ITN effectiveness and variations in the microgeographical distribution of outdoor biting.
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Affiliation(s)
- Alice Kamau
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Joseph M Mwangangi
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Integrated Vector and Disease Management Cluster, International Centre of Insect Physiology and Ecology, Nairobi, Kenya.,Pwani University Bioscience Research Centre, Pwani University, Kilifi, Kenya
| | - Martin K Rono
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Pwani University Bioscience Research Centre, Pwani University, Kilifi, Kenya
| | - Polycarp Mogeni
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Irene Omedo
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Janet Midega
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Centre for Genomics and Global Health, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - J Anthony G Scott
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, WC1E 7HT, UK
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, OX3 7FZ, UK
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13
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Kamau A, Mwangangi JM, Rono MK, Mogeni P, Omedo I, Midega J, Scott JAG, Bejon P. Variation in the effectiveness of insecticide treated nets against malaria and outdoor biting by vectors in Kilifi, Kenya. Wellcome Open Res 2018; 2:22. [DOI: 10.12688/wellcomeopenres.11073.3] [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] [Accepted: 11/06/2018] [Indexed: 11/20/2022] Open
Abstract
Background: Insecticide treated nets (ITNs) protect humans against bites from the Anopheles mosquito vectors that transmit malaria, thereby reducing malaria morbidity and mortality. It has been noted that ITN use leads to a switch from indoor to outdoor feeding among these vectors. It might be expected that outdoor feeding would undermine the effectiveness of ITNs that target indoors vectors, but data are limited. Methods: We linked homestead level geospatial data to clinical surveillance data at a primary healthcare facility in Kilifi County in order to map geographical heterogeneity in ITN effectiveness and observed vector feeding behaviour using landing catches and CDC light traps in six selected areas of varying ITN effectiveness. We quantified the interaction between mosquitoes and humans to evaluate whether outdoor vector biting is a potential explanation for the variation in ITN effectiveness. Results: We observed 37% and 46% visits associated with positive malaria slides among ITN users and non-ITN-users, respectively; ITN use was associated with 32% protection from malaria (crude OR = 0.68, 95% CI: 0.64, 0.73). We obtained significant modification of ITN effectiveness by geographical area (p=0.016), and identified significant hotspots using the spatial scan statistic. Majority of mosquitoes were caught outdoor (60%) and were of the An. funestus group (75%). The overall propensity to feed at times when most people are indoor was high; the vast majority of the Anopheles mosquitoes were caught at times when most people are indoor. Estimates for the proportion of human-mosquito contact between the first and last hour when most humans were indoor was consistently high, ranging from 0.83 to 1.00. Conclusion: Our data do not provide evidence of an epidemiological association between microgeographical variations in ITN effectiveness and variations in the microgeographical distribution of outdoor biting.
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14
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Kamau A, Mwangangi JM, Rono MK, Mogeni P, Omedo I, Midega J, Scott JAG, Bejon P. Variation in the effectiveness of insecticide treated nets against malaria and outdoor biting by vectors in Kilifi, Kenya. Wellcome Open Res 2018; 2:22. [DOI: 10.12688/wellcomeopenres.11073.2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/09/2018] [Indexed: 11/20/2022] Open
Abstract
Background: Insecticide treated nets (ITNs) protect humans against bites from the Anopheles mosquito vectors that transmit malaria, thereby reducing malaria morbidity and mortality. It has been noted that ITN use leads to a switch from indoor to outdoor feeding among these vectors. It might be expected that outdoor feeding would undermine the effectiveness of ITNs that target indoors vectors, but data are limited. Methods: We linked homestead level geospatial data to clinical surveillance data at a primary healthcare facility in Kilifi County in order to map geographical heterogeneity in ITN effectiveness and observed vector feeding behaviour using landing catches and CDC light traps in six selected areas of varying ITN effectiveness. We quantified the interaction between mosquitoes and humans to evaluate whether outdoor vector biting is a potential explanation for the variation in ITN effectiveness. Results: We observed 37% and 46% visits associated with positive malaria slides among ITN users and non-ITN-users, respectively; ITN use was associated with 32% protection from malaria (crude OR = 0.68, 95% CI: 0.64, 0.73). We obtained significant modification of ITN effectiveness by geographical area (p=0.016), and identified significant hotspots using the spatial scan statistic. Majority of mosquitoes were caught outdoor (60%) and were of the An. funestus group (75%). The overall propensity to feed at times when most people are indoor was high; the vast majority of the Anopheles mosquitoes were caught at times when most people are indoor. Estimates for the proportion of human-mosquito contact between the first and last hour when most humans were indoor was consistently high, ranging from 0.83 to 1.00. Conclusion: Our data therefore do not support the hypothesis that outdoor biting limits the effectiveness of ITNs in our study area.
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15
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Mogeni P, Williams TN, Omedo I, Kimani D, Ngoi JM, Mwacharo J, Morter R, Nyundo C, Wambua J, Nyangweso G, Kapulu M, Fegan G, Bejon P. Detecting Malaria Hotspots: A Comparison of Rapid Diagnostic Test, Microscopy, and Polymerase Chain Reaction. J Infect Dis 2017; 216:1091-1098. [PMID: 28973672 PMCID: PMC5853881 DOI: 10.1093/infdis/jix321] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 07/06/2017] [Indexed: 12/21/2022] Open
Abstract
Background Malaria control strategies need to respond to geographical hotspots of transmission. Detection of hotspots depends on the sensitivity of the diagnostic tool used. Methods We conducted cross-sectional surveys in 3 sites within Kilifi County, Kenya, that had variable transmission intensities. Rapid diagnostic test (RDT), microscopy, and polymerase chain reaction (PCR) were used to detect asymptomatic parasitemia, and hotspots were detected using the spatial scan statistic. Results Eight thousand five hundred eighty-one study participants were surveyed in 3 sites. There were statistically significant malaria hotspots by RDT, microscopy, and PCR for all sites except by microscopy in 1 low transmission site. Pooled data analysis of hotspots by PCR overlapped with hotspots by microscopy at a moderate setting but not at 2 lower transmission settings. However, variations in degree of overlap were noted when data were analyzed by year. Hotspots by RDT were predictive of PCR/microscopy at the moderate setting, but not at the 2 low transmission settings. We observed long-term stability of hotspots by PCR and microscopy but not RDT. Conclusion Malaria control programs may consider PCR testing to guide asymptomatic malaria hotspot detection once the prevalence of infection falls.
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Affiliation(s)
| | - Thomas N Williams
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,Faculty of Medicine, Imperial College London
| | - Irene Omedo
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Joyce M Ngoi
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Richard Morter
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,The Jenner Institute, Nuffield Department of Medicine, University of Oxford
| | | | | | | | - Melissa Kapulu
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford
| | - Gregory Fegan
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,Swansea Trials Unit, Swansea University Medical School, Swansea, United Kingdom
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford
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16
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Omedo I, Mogeni P, Bousema T, Rockett K, Amambua-Ngwa A, Oyier I, C Stevenson J, Y Baidjoe A, de Villiers EP, Fegan G, Ross A, Hubbart C, Jeffreys A, N Williams T, Kwiatkowski D, Bejon P. Micro-epidemiological structuring of Plasmodium falciparum parasite populations in regions with varying transmission intensities in Africa. Wellcome Open Res 2017; 2:10. [PMID: 28612053 PMCID: PMC5445974 DOI: 10.12688/wellcomeopenres.10784.2] [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] [Accepted: 09/11/2017] [Indexed: 01/10/2023] Open
Abstract
Background: The first models of malaria transmission assumed a completely mixed and homogeneous population of parasites. Recent models include spatial heterogeneity and variably mixed populations. However, there are few empiric estimates of parasite mixing with which to parametize such models. Methods: Here we genotype 276 single nucleotide polymorphisms (SNPs) in 5199
P. falciparum isolates from two Kenyan sites (Kilifi county and Rachuonyo South district) and one Gambian site (Kombo coastal districts) to determine the spatio-temporal extent of parasite mixing, and use Principal Component Analysis (PCA) and linear regression to examine the relationship between genetic relatedness and distance in space and time for parasite pairs. Results: Using 107, 177 and 82 SNPs that were successfully genotyped in 133, 1602, and 1034 parasite isolates from The Gambia, Kilifi and Rachuonyo South district, respectively, we show that there are no discrete geographically restricted parasite sub-populations, but instead we see a diffuse spatio-temporal structure to parasite genotypes. Genetic relatedness of sample pairs is predicted by relatedness in space and time. Conclusions: Our findings suggest that targeted malaria control will benefit the surrounding community, but unfortunately also that emerging drug resistance will spread rapidly through the population.
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Affiliation(s)
- Irene Omedo
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Polycarp Mogeni
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Teun Bousema
- London School of Hygiene and Tropical Medicine, London, UK.,Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands
| | - Kirk Rockett
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Isabella Oyier
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Jennifer C Stevenson
- London School of Hygiene and Tropical Medicine, London, UK.,Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Amrish Y Baidjoe
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands
| | - Etienne P de Villiers
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Department of Public Health, Pwani University, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine Research Building, University of Oxford, Oxford, UK
| | - Greg Fegan
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Amanda Ross
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Christina Hubbart
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Anne Jeffreys
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Thomas N Williams
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Department of Medicine, South Kensington Campus, Imperial College London, London, UK
| | - Dominic Kwiatkowski
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK.,Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, UK
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Centre for Clinical Vaccinology and Tropical Medicine, University of Oxford, Oxford, UK
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17
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Omedo I, Mogeni P, Bousema T, Rockett K, Amambua-Ngwa A, Oyier I, Stevenson JC, Baidjoe AY, de Villiers EP, Fegan G, Ross A, Hubbart C, Jeffreys A, Williams TN, Kwiatkowski D, Bejon P. Micro-epidemiological structuring of Plasmodium falciparum parasite populations in regions with varying transmission intensities in Africa. Wellcome Open Res 2017; 2:10. [PMID: 28612053 PMCID: PMC5445974 DOI: 10.12688/wellcomeopenres.10784.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/11/2017] [Indexed: 12/07/2023] Open
Abstract
Background: The first models of malaria transmission assumed a completely mixed and homogeneous population of parasites. Recent models include spatial heterogeneity and variably mixed populations. However, there are few empiric estimates of parasite mixing with which to parametize such models. Methods: Here we genotype 276 single nucleotide polymorphisms (SNPs) in 5199 P. falciparum isolates from two Kenyan sites (Kilifi county and Rachuonyo South district) and one Gambian site (Kombo coastal districts) to determine the spatio-temporal extent of parasite mixing, and use Principal Component Analysis (PCA) and linear regression to examine the relationship between genetic relatedness and distance in space and time for parasite pairs. Results: Using 107, 177 and 82 SNPs that were successfully genotyped in 133, 1602, and 1034 parasite isolates from The Gambia, Kilifi and Rachuonyo South district, respectively, we show that there are no discrete geographically restricted parasite sub-populations, but instead we see a diffuse spatio-temporal structure to parasite genotypes. Genetic relatedness of sample pairs is predicted by relatedness in space and time. Conclusions: Our findings suggest that targeted malaria control will benefit the surrounding community, but unfortunately also that emerging drug resistance will spread rapidly through the population.
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Affiliation(s)
- Irene Omedo
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Polycarp Mogeni
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Teun Bousema
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands
- London School of Hygiene and Tropical Medicine, London, UK
| | - Kirk Rockett
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Isabella Oyier
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Jennifer C. Stevenson
- London School of Hygiene and Tropical Medicine, London, UK
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Amrish Y. Baidjoe
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands
| | - Etienne P. de Villiers
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine Research Building, University of Oxford, Oxford, UK
- Department of Public Health, Pwani University, Kilifi, Kenya
| | - Greg Fegan
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Amanda Ross
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Christina Hubbart
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Anne Jeffreys
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Thomas N. Williams
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
- Department of Medicine, South Kensington Campus, Imperial College London, London, UK
| | - Dominic Kwiatkowski
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, UK
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
- Centre for Clinical Vaccinology and Tropical Medicine, University of Oxford, Oxford, UK
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18
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Omedo I, Mogeni P, Rockett K, Kamau A, Hubbart C, Jeffreys A, Ochola-Oyier LI, de Villiers EP, Gitonga CW, Noor AM, Snow RW, Kwiatkowski D, Bejon P. Geographic-genetic analysis of Plasmodium falciparum parasite populations from surveys of primary school children in Western Kenya. Wellcome Open Res 2017; 2:29. [PMID: 28944299 PMCID: PMC5527688 DOI: 10.12688/wellcomeopenres.11228.2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2017] [Indexed: 12/30/2022] Open
Abstract
Background. Malaria control, and finally malaria elimination, requires the identification and targeting of residual foci or hotspots of transmission. However, the level of parasite mixing within and between geographical locations is likely to impact the effectiveness and durability of control interventions and thus should be taken into consideration when developing control programs. Methods. In order to determine the geographic-genetic patterns of
Plasmodium falciparum parasite populations at a sub-national level in Kenya, we used the Sequenom platform to genotype 111 genome-wide distributed single nucleotide polymorphic (SNP) positions in 2486 isolates collected from children in 95 primary schools in western Kenya. We analysed these parasite genotypes for genetic structure using principal component analysis and assessed local and global clustering using statistical measures of spatial autocorrelation. We further examined the region for spatial barriers to parasite movement as well as directionality in the patterns of parasite movement. Results. We found no evidence of population structure and little evidence of spatial autocorrelation of parasite genotypes (correlation coefficients <0.03 among parasite pairs in distance classes of 1km, 2km and 5km; p value<0.01). An analysis of the geographical distribution of allele frequencies showed weak evidence of variation in distribution of alleles, with clusters representing a higher than expected number of samples with the major allele being identified for 5 SNPs. Furthermore, we found no evidence of the existence of spatial barriers to parasite movement within the region, but observed directional movement of parasites among schools in two separate sections of the region studied. Conclusions. Our findings illustrate a pattern of high parasite mixing within the study region. If this mixing is due to rapid gene flow, then “one-off” targeted interventions may not be currently effective at the sub-national scale in Western Kenya, due to the high parasite movement that is likely to lead to re-introduction of infection from surrounding regions. However repeated targeted interventions may reduce transmission in the surrounding regions.
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Affiliation(s)
- Irene Omedo
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Polycarp Mogeni
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Kirk Rockett
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Alice Kamau
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Christina Hubbart
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Anna Jeffreys
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | | | - Etienne P de Villiers
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Department of Public Health, Pwani University, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, OX3 7LJ, UK
| | - Caroline W Gitonga
- Spatial Health Metrics Group, Kenya Medical Research Institute-Wellcome Trust Research Programme, Nairobi, Kenya
| | - Abdisalan M Noor
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, OX3 7LJ, UK.,Spatial Health Metrics Group, Kenya Medical Research Institute-Wellcome Trust Research Programme, Nairobi, Kenya
| | - Robert W Snow
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, OX3 7LJ, UK.,Spatial Health Metrics Group, Kenya Medical Research Institute-Wellcome Trust Research Programme, Nairobi, Kenya
| | - Dominic Kwiatkowski
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK.,Wellcome Trust Sanger Institute, Cambridge, CB10 1SA, UK
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Centre for Clinical Vaccinology and Tropical Medicine, Oxford, OX3 7LJ, UK
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19
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Mogeni P, Omedo I, Nyundo C, Kamau A, Noor A, Bejon P. Effect of transmission intensity on hotspots and micro-epidemiology of malaria in sub-Saharan Africa. BMC Med 2017; 15:121. [PMID: 28662646 PMCID: PMC5492887 DOI: 10.1186/s12916-017-0887-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 06/02/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria transmission intensity is heterogeneous, complicating the implementation of malaria control interventions. We provide a description of the spatial micro-epidemiology of symptomatic malaria and asymptomatic parasitaemia in multiple sites. METHODS We assembled data from 19 studies conducted between 1996 and 2015 in seven countries of sub-Saharan Africa with homestead-level geospatial data. Data from each site were used to quantify spatial autocorrelation and examine the temporal stability of hotspots. Parameters from these analyses were examined to identify trends over varying transmission intensity. RESULTS Significant hotspots of malaria transmission were observed in most years and sites. The risk ratios of malaria within hotspots were highest at low malaria positive fractions (MPFs) and decreased with increasing MPF (p < 0.001). However, statistical significance of hotspots was lowest at extremely low and extremely high MPFs, with a peak in statistical significance at an MPF of ~0.3. In four sites with longitudinal data we noted temporal instability and variable negative correlations between MPF and average age of symptomatic malaria across all sites, suggesting varying degrees of temporal stability. CONCLUSIONS We observed geographical micro-variation in malaria transmission at sites with a variety of transmission intensities across sub-Saharan Africa. Hotspots are marked at lower transmission intensity, but it becomes difficult to show statistical significance when cases are sparse at very low transmission intensity. Given the predictability with which hotspots occur as transmission intensity falls, malaria control programmes should have a low threshold for responding to apparent clustering of cases.
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Affiliation(s)
- Polycarp Mogeni
- KEMRI-Wellcome Trust Research Programme, CGMR-Coast, Kilifi, Kenya.
| | - Irene Omedo
- KEMRI-Wellcome Trust Research Programme, CGMR-Coast, Kilifi, Kenya
| | | | - Alice Kamau
- KEMRI-Wellcome Trust Research Programme, CGMR-Coast, Kilifi, Kenya
| | - Abdisalan Noor
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, CCVTM, Oxford, UK.,Spatial Health Metrics Group, Kenya Medical Research Institute/Wellcome Trust Research Programme, Nairobi, Kenya
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, CGMR-Coast, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, CCVTM, Oxford, UK
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20
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Omedo I, Mogeni P, Rockett K, Kamau A, Hubbart C, Jeffreys A, Ochola-Oyier LI, de Villiers EP, Gitonga CW, Noor AM, Snow RW, Kwiatkowski D, Bejon P. Geographic-genetic analysis of Plasmodium falciparum parasite populations from surveys of primary school children in Western Kenya. Wellcome Open Res 2017. [DOI: 10.12688/wellcomeopenres.11228.1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [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. Malaria control, and finally malaria elimination, requires the identification and targeting of residual foci or hotspots of transmission. However, the level of parasite mixing within and between geographical locations is likely to impact the effectiveness and durability of control interventions and thus should be taken into consideration when developing control programs. Methods. In order to determine the geographic-genetic patterns of Plasmodium falciparum parasite populations at a sub-national level in Kenya, we used the Sequenom platform to genotype 111 genome-wide distributed single nucleotide polymorphic (SNP) positions in 2486 isolates collected from children in 95 primary schools in western Kenya. We analysed these parasite genotypes for genetic structure using principal component analysis and assessed local and global clustering using statistical measures of spatial autocorrelation. We further examined the region for spatial barriers to parasite movement as well as directionality in the patterns of parasite movement. Results. We found no evidence of population structure and little evidence of spatial autocorrelation of parasite genotypes (correlation coefficients <0.03 among parasite pairs in distance classes of 1km, 2km and 5km; p value<0.01). An analysis of the geographical distribution of allele frequencies showed weak evidence of variation in distribution of alleles, with clusters representing a higher than expected number of samples with the major allele being identified for 5 SNPs. Furthermore, we found no evidence of the existence of spatial barriers to parasite movement within the region, but observed directional movement of parasites among schools in two separate sections of the region studied. Conclusions. Our findings illustrate a pattern of high parasite mixing within the study region. If this mixing is due to rapid gene flow, then “one-off” targeted interventions may not be currently effective at the sub-national scale in Western Kenya, due to the high parasite movement that is likely to lead to re-introduction of infection from surrounding regions. However repeated targeted interventions may reduce transmission in the surrounding regions.
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21
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Mogeni P, Williams TN, Fegan G, Nyundo C, Bauni E, Mwai K, Omedo I, Njuguna P, Newton CR, Osier F, Berkley JA, Hammitt LL, Lowe B, Mwambingu G, Awuondo K, Mturi N, Peshu N, Snow RW, Noor A, Marsh K, Bejon P. Age, Spatial, and Temporal Variations in Hospital Admissions with Malaria in Kilifi County, Kenya: A 25-Year Longitudinal Observational Study. PLoS Med 2016; 13:e1002047. [PMID: 27352303 PMCID: PMC4924798 DOI: 10.1371/journal.pmed.1002047] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 05/11/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Encouraging progress has been seen with reductions in Plasmodium falciparum malaria transmission in some parts of Africa. Reduced transmission might lead to increasing susceptibility to malaria among older children due to lower acquired immunity, and this has implications for ongoing control strategies. METHODS AND FINDINGS We conducted a longitudinal observational study of children admitted to Kilifi County Hospital in Kenya and linked it to data on residence and insecticide-treated net (ITN) use. This included data from 69,104 children aged from 3 mo to 13 y admitted to Kilifi County Hospital between 1 January 1990 and 31 December 2014. The variation in malaria slide positivity among admissions was examined in logistic regression models using the following predictors: location of the residence, calendar time, the child's age, ITN use, and the enhanced vegetation index (a proxy for soil moisture). The proportion of malaria slide-positive admissions declined from 0.56 (95% confidence interval [CI] 0.54-0.58) in 1998 to 0.07 (95% CI 0.06-0.08) in 2009 but then increased again through to 0.24 (95% CI 0.22-0.25) in 2014. Older children accounted for most of the increase after 2009 (0.035 [95% CI 0.030-0.040] among young children compared to 0.22 [95% CI 0.21-0.23] in older children). There was a nonlinear relationship between malaria risk and prevalence of ITN use within a 2 km radius of an admitted child's residence such that the predicted malaria positive fraction varied from ~0.4 to <0.1 as the prevalence of ITN use varied from 20% to 80%. In this observational analysis, we were unable to determine the cause of the decline in malaria between 1998 and 2009, which pre-dated the dramatic scale-up in ITN distribution and use. CONCLUSION Following a period of reduced transmission, a cohort of older children emerged who have increased susceptibility to malaria. Further reductions in malaria transmission are needed to mitigate the increasing burden among older children, and universal ITN coverage is a promising strategy to achieve this goal.
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Affiliation(s)
- Polycarp Mogeni
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- * E-mail:
| | - Thomas N. Williams
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Imperial College London, London, United Kingdom
| | - Gregory Fegan
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, CCVTM, Oxford, United Kingdom
| | | | - Evasius Bauni
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Kennedy Mwai
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Irene Omedo
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Charles R. Newton
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, CCVTM, Oxford, United Kingdom
| | - Faith Osier
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - James A. Berkley
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, CCVTM, Oxford, United Kingdom
| | - Laura L. Hammitt
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Johns Hopkins Bloomberg School of Public Health, Department of International Health, Baltimore, Maryland, United States of America
| | - Brett Lowe
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Ken Awuondo
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Neema Mturi
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Norbert Peshu
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Robert W. Snow
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, CCVTM, Oxford, United Kingdom
- Spatial Health Metrics Group, Kenya Medical Research Institute/Wellcome Trust Research Programme, Nairobi, Kenya
| | - Abdisalan Noor
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, CCVTM, Oxford, United Kingdom
- Spatial Health Metrics Group, Kenya Medical Research Institute/Wellcome Trust Research Programme, Nairobi, Kenya
| | - Kevin Marsh
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, CCVTM, Oxford, United Kingdom
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, CCVTM, Oxford, United Kingdom
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