Relationship between male hydrocele and infection prevalences in clustered communities with uncertain transmission of Wuchereria bancrofti on the Thailand-Myanmar border.

A cross-sectional community-based study was conducted in three clustered communities, belonging to a single small village in Mae Chan subdistrict, Umphang district, Tak Province, close to the Thailand-Myanmar border, where regular night blood survey have been discontinued since 1997 and no epidemiological study had been conducted. In order to understand prevalences of distribution of male hydrocele and infection in clinically diagnostic and epidemiologic implications in uncertain transmission of Wuchereria bancrofti, we analyzed the relationship between male hydrocele and community infection prevalences in 219 (90.5% coverage) subjects aged > or =1 year old, including 54.8% migratory and 45.2% local Karen inhabitants. Migratory inhabitants tended to have high prevalence of antigenemia (p < 0.05) and hydrocele. Overall rates of 23.7% antigenemia, 3.7% microfilaremia, and 4.6% male hydrocele were observed. Male hydrocele prevalence was significantly correlated (r = 0.348, p < 0.0001) with antigenemia prevalence, but not with microfilaremia prevalence (r = 0.065, p = 0.493). However, high antigenemia prevalence in local inhabitants was evident, particularly antigenemia prevalence in children suggesting that transmission in the village may have occurred in recent years.