vivax circulating in Southern Thailand by using 3 antigenic markers and 8 microsatellite markers. The objective of the study is to investigate the genetic diversity of P. vivax in malaria-endemic regions such as the western part of Thailand bordering with Myanmar. In Thailand, previous studies indicated the genetic diversity of P. Plasmodium vivax is usually considered morbidity in endemic areas of Asia, Central and South America, and some part of Africa.