Genetic diversity of Plasmodium vivax population in northeast Myanmar assessed by amplicon sequencing of PvMSP1 and PvMSP3α

This study aimed to assess the baseline genetic diversity of the Plasmodium vivax population in an endemic area of northeast Myanmar at the onset of the malaria elimination campaign in the Greater Mekong Subregion. We genotyped 125 P vivax clinical samples at two merozoite surface protein loci, PvMSP1 and PvMSP3α, by amplicon deep sequencing. Our study revealed that the parasite population in this region was highly diverse, identifying 60 PvMSP1 and 98 PvMSP3α haplotypes, with haplotype diversity of 0.929 and 0.944, respectively. Remarkably, 97.6 % (122/125) of the patients harbored multiclonal infections with a mean multiplicity of infection of 4.18, indicating a relatively high transmission intensity. Neutrality tests and network analysis suggested a recent parasite population expansion, consistent with the concurrent malaria outbreak in the region. These findings underscore the existence of a highly diverse P. vivax population at the China-Myanmar border, highlighting the need for effective malaria control strategies to achieve the goal of regional malaria elimination.