A thirty years follow-up study on Schistosomiasis mansoni in a community of Minas Gerais, Brazil

ABSTRACT

During thirty years - 1973-2003 - a group of individuals infected by Schistosoma mansoni in Capitão Andrade, Rio Doce Valley, Minas Gerais, Brazil, was evaluated by the same authors, being one of the longest follow-up studies on schistosomiasisis mansoni in an endemic area. The diagnosis of S. mansoni was based on parasitological stool tests. In the clinical classification, three groups were considered type I - schistosomiasis-infection, type II - hepatointestinal form, and type III- hepatosplenic form. The prevalence of infection were 60.8 percent in 1973, 36.2 percent in 1984, 27.3 percent in 1994, and 19.4 percent in 2003, while the index of hepatosplenomegaly were respectively 5.8 percent, 2.8 percent, 2.3 percent and 1.3 percent. The maintenance of high prevalence and severity of clinical forms are probably related to reinfection.