Evidence map›Paper›PMID 35232492›Full record

ArticleTropical medicine and health2022

Reduction in Plasmodium falciparum Pfk13 and pfg377 allele diversity through time in southern Vietnam.

Nguyen Quang Thieu, Vu Duc Chinh, Truong Van Hanh, Nguyen Van Dung, Hidekazu Takagi, Takeshi Annoura, Satoru Kawai, Gaku Masuda, Nguyen Van Tuan, Vu Viet Hung and 4 more

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Article in Tropical medicine and health, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

14 authors at 9 institutions in 2 countries.

Nguyen Quang ThieuNational Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam.
Vu Duc ChinhNational Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam.
Truong Van HanhNational Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam.
Nguyen Van DungNational Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam.
Hidekazu TakagiDepartment of Microbiology and Immunology, Aichi Medical University School of Medicine, Aichi, Japan.
Takeshi AnnouraDepartment of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan.
Satoru KawaiLaboratory of Tropical Medicine and Parasitology, Dokkyo Medical University, Tochigi, Japan.
Gaku MasudaDepartment of International Affairs and Tropical Medicine, Tokyo Women's Medical University, Tokyo, Japan.
Nguyen Van TuanFaculty of Medical Engineering, Phenikaa University, Hanoi, Vietnam.
Vu Viet HungNational Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam.
Shusuke NakazawaDepartment of Protozoology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
Richard CulletonDepartment of Protozoology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
Nguyen Thi Huong BinhNational Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam.
Yoshimasa MaenoSchool of Tropical Medicine and Global Health, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, Nagasaki, 852-8523, Japan. yoshimaeno@gmail.com.ORCID http://orcid.org/0000-0002-9626-4363
National Institute of Malariology, Parasitology and Entomology · VNAichi Medical University · JPDokkyo Medical University · JPEhime University · JPFujita Health University · JPNagasaki University · JPNational Institute of Infectious Diseases · JPPhenikaa University · VNTokyo Women's Medical University · JP

Funding

Japan Society for the Promotion of Science 17H04513Japan Society for the Promotion of Science 20H04411Japan Society for the Promotion of Science 26360029
6 · The paper itself

Abstract

backgroundPlasmodium falciparum has acquired resistance to artemisinin in Southeast Asia, with mutations in the P. falciparum Kelch-13 (Pfk13) gene associated with the resistance phenotype. The widespread use of Artemisinin-based combination therapy (ACT)s in Southeast Asia has led to the selection and spread of parasites carrying mutations in Pfk13. We characterised the allele diversity of Pfk13 and pfg377, an artemisinin-resistance neutral polymorphic gene, in parasite DNA extracted human blood from in southern Vietnam in 2003, 2012, 2015 and 2018.

methodThis study was conducted in Bu Gia Map commune, Binh Phuoc province, Vietnam, from May 2018 to January 2019. Twenty-four samples from 2018 to 2019, 30 from 2003, 24 from 2012 and 32 from 2015 were analysed. Malaria-infected human blood was collected by finger-prick and used for molecular analysis. A nested-PCR targeting the small subunit ribosomal RNA gene was used for Plasmodium species identification, followed by amplification and nucleotide sequencing of Pfk13 and region 3 of pfg377. Archived blood samples collected in the same region in 2012 and 2015 were also analysed as above for comparison.

resultsThe genetic diversity of Pfk13 and pfg377 was lower in 2018-2019 compared to 2012 and 2015. The number of distinct Pfk13 mutants decreased from three in 2012 and 2015, P553L, V568G and C580Y, to one, C580Y in 2018-2019. In 2018-2019, the frequency of C580Y mutant strains was 71% (17/24 isolates). All samples were wild type in 2003. In 2012 and 2015, there were single-strain infections as well as co-infections with two mutant strains or with mutant and wild strains, whereas there were no co-infections in 2018. pfg377 allele diversity decreased from five alleles in 2012 to two alleles in 2018-2019.

conclusionThe genetic diversity of P. falciparum was reduced at the two genetic loci surveyed in this study, Pfk13 and pfg377. In the case of the former gene, we observed an increase in the prevalence of parasites carrying the C580Y gene, known to confer reduced susceptibility to ACTs. The reduction in the diversity of pfg377 may be linked to the clonal expansion of parasite strains carrying the C580Y mutation, leading to an overall reduction in parasite genetic diversity across the population.

Indexed as

Artemisinin resistanceGametocyteK13-propeller genepfg377 genePlasmodium falciparumVietnam

Identifiers

PMID35232492
PMCPMC8887123
OpenAlexW4214606879

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