Four polymorphic genes were used for identification and characterization of malaria parasite P. vivax are: Pvcs coding for the circumsporozoite protein, Pvmspl and Pvmsp3a coding for the merozoite protein 1 and 3 alpha and Pvgaml coding for a gametocyte antigen. The study investigated genetic diversity of P. vivax populations based on Pvcs and Pvmspl genes in 34 isolates collected from Quang Binh province by PCR. The results indicated that P. vivax populations in Quang Binh are high diverse genetically. - Pvcs gene, the results showed that VK210 genotype contains 53.66 percent and 5 allelic variations with size from 671 to 778 bp, VK247 genotype contains 46.34 percent and 4 allelic variations with size from 697 to 778 bp, mixed genotypes infection found in 20.59 percent of samples, MOl value is 1.21. - Pvmspl gene, the results showed that Fl fragment has found 3 allelic variations with size from 360 to 460 bp, MOl value is 1.23
F2 segment has 5 allelic variations with size from 1130 to 1280 bp, MOl is 1.18 and F3 segment has 4 allelic variations with size from 250 to 340 bp, MOl is 1.29.