Well-breeding Anopheles dirus and their role in malaria transmission in Myanmar

Mosquitos were collected with human and animal baits from March 1996 to January 1998 in four villages located along the Yadana gas pipe line in Yepyu township, Dawae district, Tanintharyi Division, southern Myanmar. A total of 23 anopheline species were collected. Anopheles dirus were abundant in pre-monsoon (May/June) an post-monsoon (October) months. All An. dirus caught both humans and cattle were assayed with specific, sporozoite enzyme-linked immunosorbent assays (ELISAs). A total of 5/250 (2%) caught with human bait was found positive with Plasmodium vivax from Eindayaza, Ohnbinkwin and Thaechaung during rainy and cool-dry months. Larval surveys also showed An. dirus larvae/pupae were caught from domestic wells (6 to 46% found positive). Clinical surveys indicated that transmission is hyperendemic and occur all year round in all four villages.