ArticleThe Lancet. Infectious diseases2023
Malaria outbreak in Laos driven by a selective sweep for Plasmodium falciparum kelch13 R539T mutants: a genetic epidemiology analysis.
Article in The Lancet. Infectious diseases, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 28 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
28 citing papers in PubMed.
- Building the toolkit to address malaria resurgence and radical cure of vivax malaria in Ethiopia: a meeting report.Malaria journal · 2026Article
- Impact of intensive control on malaria population genomics under elimination settings in Southeast Asia.Nature microbiology · 2026Article
- Double Mutations inbioRxiv : the preprint server for biology · 2026Article
- A six-pronged approach to manage a Plasmodium vivax outbreak in a low- and middle-income country on the road to malaria elimination.PLoS neglected tropical diseases · 2026Article
- Genomics in Epidemiology and Disease Surveillance: An Exploratory Analysis.Life (Basel, Switzerland) · 2025Review
- Review
- Epigenetically conferred ring-stage survival in Plasmodium falciparum against artemisinin treatment.Nature communications · 2025Article
- Malaria: past, present, and future.Signal transduction and targeted therapy · 2025Review
- The limitations of mobile phone data for measuring movement patterns of populations at risk of malaria.Malaria journal · 2025Observational
- Genetic surveillance of Plasmodium falciparum populations following treatment policy revisions in the Greater Mekong Subregion.Nature communications · 2025Article
- NovelAntimicrobial agents and chemotherapy · 2025Article
- Bridging the Gap from Molecular Surveillance to Programmatic Decisions for Malaria Control and Elimination.The American journal of tropical medicine and hygiene · 2025Review
- Detecting imported malaria infections in endemic settings using molecular surveillance: current state and challenges.Frontiers in epidemiology · 2025Review
- Geo-classification of drug-resistant travel-associatedAntimicrobial agents and chemotherapy · 2024Article
- The emergence of artemisinin partial resistance in Africa: how do we respond?The Lancet. Infectious diseases · 2024Review
- Genomic epidemiology demonstrates spatially clustered, local transmission of Plasmodium falciparum in forest-going populations in southern Lao PDR.PLoS pathogens · 2024Article
- AmBio · 2024Article
- Emergence, transmission dynamics and mechanisms of artemisinin partial resistance in malaria parasites in Africa.Nature reviews. Microbiology · 2024Review
- Malaria epidemiology, surveillance and response for elimination in Lao PDR.Infectious diseases of poverty · 2024Review
- Analytic Approaches in Genomic Epidemiological Studies of Parasitic Protozoa.Transboundary and emerging diseases · 2024Review
Corrections and comments
- Commented on by
Authors and funding
17 authors.
Funding
Abstract
backgroundMalaria outbreaks are important public health concerns that can cause resurgence in endemic regions approaching elimination. We investigated a Plasmodium falciparum outbreak in Attapeu Province, Laos, during the 2020-21 malaria season, using genomic epidemiology methods to elucidate parasite population dynamics and identify its causes.
methodsIn this genetic analysis, 2164 P falciparum dried blood spot samples were collected from southern Laos between Jan 1, 2017, and April 1, 2021, which included 249 collected during the Attapeu outbreak between April 1, 2020, and April 1, 2021, by routine surveillance. Genetic barcodes obtained from these samples were used to investigate epidemiological changes underpinning the outbreak, estimate population diversity, and analyse population structure. Whole-genome sequencing data from additional historical samples were used to reconstruct the ancestry of outbreak strains using identity-by-descent analyses.
findingsThe outbreak parasite populations were characterised by unprecedented loss of genetic diversity, primarily caused by rapid clonal expansion of a multidrug-resistant strain (LAA1) carrying the kelch13 Arg539Thr (R539T) mutation. LAA1 replaced kelch13 Cys580Tyr (C580Y) mutants resistant to dihydroartemisinin-piperaquine (KEL1/PLA1) as the dominant strain. LAA1 inherited 58·8% of its genome from a strain circulating in Cambodia in 2008. A secondary outbreak strain (LAA2) carried the kelch13 C580Y allele, and a genome that is essentially identical to a Cambodian parasite from 2009. A third, low-frequency strain (LAA7) was a recombinant of KEL1/PLA1 with a kelch13 R539T mutant.
interpretationThese results strongly suggest that the outbreak was driven by a selective sweep, possibly associated with multidrug-resistant phenotypes of the outbreak strains. Established resistant populations can circulate at low frequencies for years before suddenly overwhelming dominant strains when the conditions for selection become favourable-eg, when front-line therapies change. Genetic surveillance can support elimination by characterising key properties of outbreaks such as population diversity, drug resistance marker prevalence, and the origins of outbreak strains.
fundingBill & Melinda Gates Foundation; The Global Fund to Fight AIDS, Tuberculosis and Malaria; Wellcome Trust. TRANSLATION: For the Lao translation of the abstract see Supplementary Materials section.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.