Open AccessSubstantial population structure of Plasmodium vivax in Thailand facilitates identification of the sources of residual transmission
Author(s) -
Veerayuth Kittichai,
Cristian Koepfli,
Wang Nguitragool,
Jetsumon Sattabongkot,
Liwang Cui
Publication year - 2017
Publication title -
plos neglected tropical diseases
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.99
H-Index - 135
eISSN - 1935-2735
pISSN - 1935-2727
DOI - 10.1371/journal.pntd.0005930
Subject(s) - biology , microsatellite , plasmodium vivax , genotyping , genetic diversity , malaria , population , gene flow , genetic structure , transmission (telecommunications) , parasite hosting , haplotype , population genetics , plasmodium falciparum , genetic variation , evolutionary biology , genetics , genotype , gene , allele , demography , immunology , electrical engineering , engineering , world wide web , computer science , sociology
Background Plasmodium vivax transmission in Thailand has been substantially reduced over the past 10 years, yet it remains highly endemic along international borders. Understanding the genetic relationship of residual parasite populations can help track the origins of the parasites that are reintroduced into malaria-free regions within the country. Methodology/Results A total of 127 P . vivax isolates were genotyped from two western provinces (Tak and Kanchanaburi) and one eastern province (Ubon Ratchathani) of Thailand using 10 microsatellite markers. Genetic diversity was high, but recent clonal expansion was detected in all three provinces. Substantial population structure and genetic differentiation of parasites among provinces suggest limited gene flow among these sites. There was no haplotype sharing among the three sites, and a reduced panel of four microsatellite markers was sufficient to assign the parasites to their provincial origins. Conclusion/Significance Significant parasite genetic differentiation between provinces shows successful interruption of parasite spread within Thailand, but high diversity along international borders implies a substantial parasite population size in these regions. The provincial origin of P . vivax cases can be reliably determined by genotyping four microsatellite markers, which should be useful for monitoring parasite reintroduction after malaria elimination.