Schistosomiasis and Limnology in the Amazon Region

Abstract

Summary The limnological conditions at Fordlandia (State of Pará, Brazil), at present the only known place with endemic schistosomiasis mansoni in the entire Amazonian region, are propitious for the development of planorbid snails since the Carboniferous formation is responsible for surface waters of almost neutral reaction, which seems to be a requisite for survival and multiplication of these snails, as shown by surveys of many Amazonian areas where waters are acid and these snails are absent. It is concluded that, with colonization by immigrants from Northeast Brazil and other regions infected with schistosomiasis, the disease may become endemic in the regions with Carboniferous strata north and south of the Amazon, but there is little danger of this in the rest of the great area of the Amazon basin.