Genetic surveillance project conducted by the National Malaria Control Programme in partnership with GenRe-Mekong in endemic regions of Cambodia. This is part of a large project of genetic surveillance of malaria in the Greater Mekong Subregion, funded by the Bill and Melinda Gates Foundation. Dried blood spot (DBS) samples are to be collected along with short surveys on patient demographics and population movement from every confirmed case of Plasmodium falciparum and/or Plasmodium vivax malaria presenting at public health facilities. The aim is to determine the prevalence and geographic distribution of antimalarial drug resistance-linked genetic mutations, as well as the genetic structure of the parasite population, likely routes of gene flow between populations, and geographic origins of parasites.