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Kattenberg JH, Monsieurs P, De Meyer J, De Meulenaere K, Sauve E, de Oliveira TC, Ferreira MU, Gamboa D, Rosanas‐Urgell A. Population genomic evidence of structured and connected Plasmodium vivax populations under host selection in Latin America. Ecol Evol 2024; 14:e11103. [PMID: 38529021 PMCID: PMC10961478 DOI: 10.1002/ece3.11103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 02/15/2024] [Accepted: 02/20/2024] [Indexed: 03/27/2024] Open
Abstract
Pathogen genomic epidemiology has the potential to provide a deep understanding of population dynamics, facilitating strategic planning of interventions, monitoring their impact, and enabling timely responses, and thereby supporting control and elimination efforts of parasitic tropical diseases. Plasmodium vivax, responsible for most malaria cases outside Africa, shows high genetic diversity at the population level, driven by factors like sub-patent infections, a hidden reservoir of hypnozoites, and early transmission to mosquitoes. While Latin America has made significant progress in controlling Plasmodium falciparum, it faces challenges with residual P. vivax. To characterize genetic diversity and population structure and dynamics, we have analyzed the largest collection of P. vivax genomes to date, including 1474 high-quality genomes from 31 countries across Asia, Africa, Oceania, and America. While P. vivax shows high genetic diversity globally, Latin American isolates form a distinctive population, which is further divided into sub-populations and occasional clonal pockets. Genetic diversity within the continent was associated with the intensity of transmission. Population differentiation exists between Central America and the North Coast of South America, vs. the Amazon Basin, with significant gene flow within the Amazon Basin, but limited connectivity between the Northwest Coast and the Amazon Basin. Shared genomic regions in these parasite populations indicate adaptive evolution, particularly in genes related to DNA replication, RNA processing, invasion, and motility - crucial for the parasite's survival in diverse environments. Understanding these population-level adaptations is crucial for effective control efforts, offering insights into potential mechanisms behind drug resistance, immune evasion, and transmission dynamics.
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Affiliation(s)
| | - Pieter Monsieurs
- Malariology UnitInstitute of Tropical Medicine AntwerpAntwerpBelgium
| | - Julie De Meyer
- Malariology UnitInstitute of Tropical Medicine AntwerpAntwerpBelgium
- Present address:
Integrated Molecular Plant physiology Research (IMPRES) and Plants and Ecosystems (PLECO), Department of BiologyUniversity of AntwerpAntwerpBelgium
| | | | - Erin Sauve
- Malariology UnitInstitute of Tropical Medicine AntwerpAntwerpBelgium
| | - Thaís C. de Oliveira
- Department of Parasitology, Institute of Biomedical SciencesUniversity of São PauloSão PauloBrazil
| | - Marcelo U. Ferreira
- Department of Parasitology, Institute of Biomedical SciencesUniversity of São PauloSão PauloBrazil
- Global Health and Tropical Medicine, Institute of Hygiene and Tropical MedicineNova University of LisbonLisbonPortugal
| | - Dionicia Gamboa
- Instituto de Medicina Tropical “Alexander von Humboldt”Universidad Peruana Cayetano HerediaLimaPeru
- Laboratorio de Malaria: Parásitos y Vectores, Laboratorios de Investigación y Desarrollo, Departamento de Ciencias Celulares y Moleculares, Facultad de Ciencias e IngenieríaUniversidad Peruana Cayetano HerediaLimaPeru
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Ruybal-Pesántez S, McCann K, Vibin J, Siegel S, Auburn S, Barry AE. Molecular markers for malaria genetic epidemiology: progress and pitfalls. Trends Parasitol 2024; 40:147-163. [PMID: 38129280 DOI: 10.1016/j.pt.2023.11.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/13/2023] [Accepted: 11/14/2023] [Indexed: 12/23/2023]
Abstract
Over recent years, progress in molecular markers for genotyping malaria parasites has enabled informative studies of epidemiology and transmission dynamics. Results have highlighted the value of these tools for surveillance to support malaria control and elimination strategies. There are many different types and panels of markers available for malaria parasite genotyping, and for end users, the nuances of these markers with respect to 'use case', resolution, and accuracy, are not well defined. This review clarifies issues surrounding different molecular markers and their application to malaria control and elimination. We describe available marker panels, use cases, implications for different transmission settings, limitations, access, cost, and data accuracy. The information provided can be used as a guide for molecular epidemiology and surveillance of malaria.
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Affiliation(s)
- Shazia Ruybal-Pesántez
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, UK; Institute of Microbiology, Universidad San Francisco de Quito, Quito, Ecuador
| | - Kirsty McCann
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; Centre for Innovation in Infectious Disease and Immunology Research (CIIDIR), Institute for Mental and Physical Health and Clinical Translation (IMPACT) and School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Jessy Vibin
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; Centre for Innovation in Infectious Disease and Immunology Research (CIIDIR), Institute for Mental and Physical Health and Clinical Translation (IMPACT) and School of Medicine, Deakin University, Geelong, Victoria, Australia
| | | | - Sarah Auburn
- Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia; Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
| | - Alyssa E Barry
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia; Centre for Innovation in Infectious Disease and Immunology Research (CIIDIR), Institute for Mental and Physical Health and Clinical Translation (IMPACT) and School of Medicine, Deakin University, Geelong, Victoria, Australia.
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Rovira-Vallbona E, Kattenberg JH, Hong NV, Guetens P, Imamura H, Monsieurs P, Chiheb D, Erhart A, Phuc BQ, Xa NX, Rosanas-Urgell A. Molecular surveillance of Plasmodium falciparum drug-resistance markers in Vietnam using multiplex amplicon sequencing (2000-2016). Sci Rep 2023; 13:13948. [PMID: 37626131 PMCID: PMC10457381 DOI: 10.1038/s41598-023-40935-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 08/18/2023] [Indexed: 08/27/2023] Open
Abstract
Emergence and spread of Plasmodium falciparum resistance to artemisinin-based combination therapies (ACT) is a major challenge for Greater Mekong Subregion countries in their goal to eliminate malaria by 2030. Tools to efficiently monitor drug resistance beyond resource-demanding therapeutic efficacy studies are necessary. A custom multiplex amplicon sequencing assay based on Illumina technology was designed to target the marker of partial resistance to artemisinin (K13), five candidate modulators of artemisinin resistance, the marker of resistance to chloroquine (crt), and four neutral microsatellite loci. The assay was used to genotype 635 P. falciparum-positive blood samples collected across seven provinces of Vietnam and one of Cambodia between 2000 and 2016. Markers of resistance to artemisinin partner-drugs piperaquine (copy number of plasmepsin-2) and mefloquine (copy number of multidrug-resistance 1) were determined by qPCR. Parasite population structure was further assessed using a 101-SNP barcode. Validated mutations of artemisinin partial resistance in K13 were found in 48.1% of samples, first detection was in 2000, and by 2015 prevalence overcame > 50% in Central Highlands and Binh Phuoc province. K13-C580Y variant became predominant country-wide, quickly replacing an outbreak of K13-I543T in Central Highlands. Mutations in candidate artemisinin resistance modulator genes paralleled the trends of K13 mutants, whereas resistance to piperaquine and mefloquine remained low (≈ 10%) by 2015-2016. Genomic tools applied to malaria surveillance generate comprehensive information on dynamics of drug resistance and population structure and reflect drug efficacy profiles from in vivo studies.
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Affiliation(s)
- Eduard Rovira-Vallbona
- Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
- ISGlobal, Hospital Clínic/Universitat de Barcelona, 08036, Barcelona, Catalonia, Spain
| | | | - Nguyen Van Hong
- National Institute of Malariology, Parasitology and Entomology, Hanoi, 10200, Vietnam
| | - Pieter Guetens
- Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
| | - Hideo Imamura
- Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
- Vrije Universiteit Brussel, Campus Jette, 1090, Brussels, Belgium
- UZ Brussel, Centre for Medical Genetics, 1090, Brussels, Belgium
| | - Pieter Monsieurs
- Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
| | - Driss Chiheb
- Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
| | - Annette Erhart
- Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
- Medical Research Council Unit, The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Bui Quang Phuc
- National Institute of Malariology, Parasitology and Entomology, Hanoi, 10200, Vietnam
| | - Nguyen Xuan Xa
- National Institute of Malariology, Parasitology and Entomology, Hanoi, 10200, Vietnam
| | - Anna Rosanas-Urgell
- Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium.
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Leonard SR, Mammel MK, Gharizadeh B, Almeria S, Ma Z, Lipman DJ, Torrence ME, Wang C, Musser SM. Development of a targeted amplicon sequencing method for genotyping Cyclospora cayetanensis from fresh produce and clinical samples with enhanced genomic resolution and sensitivity. Front Microbiol 2023; 14:1212863. [PMID: 37396378 PMCID: PMC10311907 DOI: 10.3389/fmicb.2023.1212863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 05/31/2023] [Indexed: 07/04/2023] Open
Abstract
Outbreaks of cyclosporiasis, an enteric illness caused by the parasite Cyclospora cayetanensis, have been associated with consumption of various types of fresh produce. Although a method is in use for genotyping C. cayetanensis from clinical specimens, the very low abundance of C. cayetanensis in food and environmental samples presents a greater challenge. To complement epidemiological investigations, a molecular surveillance tool is needed for use in genetic linkage of food vehicles to cyclosporiasis illnesses, estimation of the scope of outbreaks or clusters of illness, and determination of geographical areas involved. We developed a targeted amplicon sequencing (TAS) assay that incorporates a further enrichment step to gain the requisite sensitivity for genotyping C. cayetanensis contaminating fresh produce samples. The TAS assay targets 52 loci, 49 of which are located in the nuclear genome, and encompasses 396 currently known SNP sites. The performance of the TAS assay was evaluated using lettuce, basil, cilantro, salad mix, and blackberries inoculated with C. cayetanensis oocysts. A minimum of 24 markers were haplotyped even at low contamination levels of 10 oocysts in 25 g leafy greens. The artificially contaminated fresh produce samples were included in a genetic distance analysis based on haplotype presence/absence with publicly available C. cayetanensis whole genome sequence assemblies. Oocysts from two different sources were used for inoculation, and samples receiving the same oocyst preparation clustered together, but separately from the other group, demonstrating the utility of the assay for genetically linking samples. Clinical fecal samples with low parasite loads were also successfully genotyped. This work represents a significant advance in the ability to genotype C. cayetanensis contaminating fresh produce along with greatly expanding the genomic diversity included for genetic clustering of clinical specimens.
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Affiliation(s)
- Susan R. Leonard
- Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD, United States
| | - Mark K. Mammel
- Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD, United States
| | | | - Sonia Almeria
- Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD, United States
| | - Zhihai Ma
- Chapter Diagnostics, Menlo Park, CA, United States
| | - David J. Lipman
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, United States
| | - Mary E. Torrence
- Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD, United States
| | - Chunlin Wang
- Chapter Diagnostics, Menlo Park, CA, United States
| | - Steven M. Musser
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, United States
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Trimarsanto H, Amato R, Pearson RD, Sutanto E, Noviyanti R, Trianty L, Marfurt J, Pava Z, Echeverry DF, Lopera-Mesa TM, Montenegro LM, Tobón-Castaño A, Grigg MJ, Barber B, William T, Anstey NM, Getachew S, Petros B, Aseffa A, Assefa A, Rahim AG, Chau NH, Hien TT, Alam MS, Khan WA, Ley B, Thriemer K, Wangchuck S, Hamedi Y, Adam I, Liu Y, Gao Q, Sriprawat K, Ferreira MU, Laman M, Barry A, Mueller I, Lacerda MVG, Llanos-Cuentas A, Krudsood S, Lon C, Mohammed R, Yilma D, Pereira DB, Espino FEJ, Chu CS, Vélez ID, Namaik-Larp C, Villegas MF, Green JA, Koh G, Rayner JC, Drury E, Gonçalves S, Simpson V, Miotto O, Miles A, White NJ, Nosten F, Kwiatkowski DP, Price RN, Auburn S. A molecular barcode and web-based data analysis tool to identify imported Plasmodium vivax malaria. Commun Biol 2022; 5:1411. [PMID: 36564617 PMCID: PMC9789135 DOI: 10.1038/s42003-022-04352-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 12/08/2022] [Indexed: 12/25/2022] Open
Abstract
Traditionally, patient travel history has been used to distinguish imported from autochthonous malaria cases, but the dormant liver stages of Plasmodium vivax confound this approach. Molecular tools offer an alternative method to identify, and map imported cases. Using machine learning approaches incorporating hierarchical fixation index and decision tree analyses applied to 799 P. vivax genomes from 21 countries, we identified 33-SNP, 50-SNP and 55-SNP barcodes (GEO33, GEO50 and GEO55), with high capacity to predict the infection's country of origin. The Matthews correlation coefficient (MCC) for an existing, commonly applied 38-SNP barcode (BR38) exceeded 0.80 in 62% countries. The GEO panels outperformed BR38, with median MCCs > 0.80 in 90% countries at GEO33, and 95% at GEO50 and GEO55. An online, open-access, likelihood-based classifier framework was established to support data analysis (vivaxGEN-geo). The SNP selection and classifier methods can be readily amended for other use cases to support malaria control programs.
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Affiliation(s)
- Hidayat Trimarsanto
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Roberto Amato
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | | | - Edwin Sutanto
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
- Exeins Health Initiative, Jakarta, Indonesia
| | | | - Leily Trianty
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Jutta Marfurt
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Zuleima Pava
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Diego F Echeverry
- International Training and Medical Research Center (CIDEIM), Cali, Colombia
- Departamento de Microbiología, Universidad del Valle, Cali, Colombia
- Universidad Icesi, Cali, Colombia
| | | | | | | | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Bridget Barber
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Timothy William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
- Clinical Research Centre, Queen Elizabeth Hospital, Sabah, Malaysia
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Sisay Getachew
- College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Beyene Petros
- College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Abraham Aseffa
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | | | - Awab G Rahim
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Nangarhar Medical Faculty, Nangarhar University, Ministry of Higher Education, Jalalabad, Afghanistan
| | - Nguyen H Chau
- Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam
| | - Tran T Hien
- Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam
| | - Mohammad S Alam
- Infectious Diseases Division, International Centre for Diarrheal Diseases Research, Dhaka, Bangladesh
| | - Wasif A Khan
- Infectious Diseases Division, International Centre for Diarrheal Diseases Research, Dhaka, Bangladesh
| | - Benedikt Ley
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Kamala Thriemer
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Sonam Wangchuck
- Royal Center for Disease Control, Department of Public Health, Ministry of Health, Thimphu, Bhutan
| | - Yaghoob Hamedi
- Infectious and Tropical Diseases Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Hormozgan Province, Iran
| | - Ishag Adam
- Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | - Yaobao Liu
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China
- School of Public Health, Nanjing Medical University, Nanjing, China
| | - Qi Gao
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China
| | - Kanlaya Sriprawat
- Shoklo Malaria Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
| | - Marcelo U Ferreira
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- Global Health and Tropical Medicine, Institute of Hygiene and Tropical Medicine, NOVA University of Lisbon, Lisbon, Portugal
| | - Moses Laman
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Alyssa Barry
- Deakin University, Victoria, Australia
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Victoria, Australia
- Department of Medical Biology, The University of Melbourne, Victoria, Australia
| | - Ivo Mueller
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Victoria, Australia
- Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Marcus V G Lacerda
- Fundação de Medicina Tropical, Manaus, Brazil
- Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
| | | | | | - Chanthap Lon
- Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | | | | | | | - Fe E J Espino
- Research Institute for Tropical Medicine, Manilla, Philippines
| | - Cindy S Chu
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Shoklo Malaria Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
| | - Iván D Vélez
- Malaria Group, Universidad de Antioquia, Medellin, Colombia
| | | | | | | | | | - Julian C Rayner
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
- Cambridge Institute for Medical Research, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Eleanor Drury
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Sónia Gonçalves
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Victoria Simpson
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Olivo Miotto
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
| | - Alistair Miles
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Nicholas J White
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Francois Nosten
- Shoklo Malaria Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | - Ric N Price
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Sarah Auburn
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia.
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
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