Population Genetics of Plasmodium vivax in Four Rural Communities in Central Vietnam

• Published in: PLoS neglected tropical diseases Vol. 10; no. 2; p. e0004434
• Main Authors: Hong, Nguyen Van, Delgado-Ratto, Christopher, Thanh, Pham Vinh, Van den Eede, Peter, Guetens, Pieter, Binh, Nguyen Thi Huong, Phuc, Bui Quang, Duong, Tran Thanh, Van Geertruyden, Jean Pierre, D'Alessandro, Umberto, Erhart, Annette, Rosanas-Urgell, Anna
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 12.02.2016; Public Library of Science (PLoS)
• Subjects: Adolescent; Adult; Analysis; Biodiversity; Biology and Life Sciences; Child; Child, Preschool; Drug resistance; Earth Sciences; Ecology and Environmental Sciences; Female; Freshwater; Genetic aspects; Genetic diversity; Genetic Variation; Genotype; Haplotypes; Health aspects; Humans; Infections; Malaria; Malaria, Vivax - epidemiology; Malaria, Vivax - parasitology; Male; Medicine and Health Sciences; Microsatellite Repeats; Molecular Sequence Data; Multiculturalism & pluralism; Parasites; People and Places; Phylogeny; Plasmodium vivax; Plasmodium vivax - classification; Plasmodium vivax - genetics; Plasmodium vivax - isolation & purification; Population genetics; Risk factors; Rural areas; Rural Population; Vietnam - epidemiology; Young Adult; Vietnam; ISEW, Vietnam
• ISSN: 1935-2735; 1935-2727; 1935-2735
• DOI: 10.1371/journal.pntd.0004434

The burden of malaria in Vietnam has drastically reduced, prompting the National Malaria Control Program to officially engage in elimination efforts. Plasmodium vivax is becoming increasingly prevalent, remaining a major problem in the country's central and southern provinces. A better understanding of P. vivax genetic diversity and structure of local parasite populations will provide baseline data for the evaluation and improvement of current efforts for control and elimination. The aim of this study was to examine the population genetics and structure of P. vivax isolates from four communities in Tra Leng commune, Nam Tra My district in Quang Nam, Central Vietnam. P. vivax mono infections collected from 234 individuals between April 2009 and December 2010 were successfully analyzed using a panel of 14 microsatellite markers. Isolates displayed moderate genetic diversity (He = 0.68), with no significant differences between study communities. Polyclonal infections were frequent (71.4%) with a mean multiplicity of infection of 1.91 isolates/person. Low but significant genetic differentiation (FST value from -0.05 to 0.18) was observed between the community across the river and the other communities. Strong linkage disequilibrium ([Formula: see text] = 0.113, p < 0.001) was detected across all communities, suggesting gene flow within and among them. Using multiple approaches, 101 haplotypes were grouped into two genetic clusters, while 60.4% of haplotypes were admixed. In this area of Central Vietnam, where malaria transmission has decreased significantly over the past decade, there was moderate genetic diversity and high occurrence of polyclonal infections. Local human populations have frequent social and economic interactions that facilitate gene flow and inbreeding among parasite populations, while decreasing population structure. Findings provide important information on parasites populations circulating in the study area and are relevant to current malaria elimination efforts.