Figure 4.
Study area and study site. (a) MRP ecotope at Khlong Khak village, Bo Rai district, Trat Province, elicited a malaria outbreak in 2013-2014. All malarial infections were epidemiologically linked with the indigenous Plasmodium infections in four separate MRP polygons within a 1.5 km2 MRP ecotope infested with Anopheles vectors. Data were modified from Kaewwaen and Bhumiratana [6]. (b) As similar to the other Anopheles sampling site I, the Anopheles sampling site II reflected households with rubber plantation practices whose members acquired the Plasmodium infections through mosquito-borne transmission. This MRP ecotope had strong density of Anopheles larval breeding sites. It was used in periodic assessment of species composition, abundance, and blood-feeding behaviors of Anopheles vectors at a house of rubber plantation polygon TBDKK3C as a study site. (c) A IRS-protected house of TBDKK3C polygon was used to collect Anopheles vector population samples by human landing catches. The distance of this IRS-protected house was estimated using the nearest certain Anopheles larval breeding sites within Khlong Khak MRP ecotope. The IRS using BT was described in detail in the text.