Correlated prevalence of hydrocele and microfilaremia in Amazon (Belém, 1951-2005).

Background & Objectives: For decades, the city of Belém in Brazil's eastern Amazon was the second city in the country with highest prevalence of cases of filariasis due to Wuchereria bancrofti infection. However, this prevalence decreased over time until reaching null records, concomitantly with a decrease in frequency of recorded hydrocele cases. In this context, we analyzed cross-sectional data to evaluate the degree of correlation between prevalence of positive blood microfilariae results during surveillance screening occurred along 54 years (1951-2005) and prevalence of hydrocele cases recorded in the same time period.