This paper is a report of the first results of a more complex research based on geoprocessessing , remote sensing and GIS, in the studies of schistosomiasis distribution in Minas Gerais state, Brazil. The goal of the global project is the identification of correlations between environmental variables and the occurrence and diffusion of the intermediate disease vector (snails of several species) and the disease itself, in order to identify the potential of risk areas. The focus of this paper is on studies related to hydrological factors, to develop an index of water accessibility, as one of the hypotheses to be verified is the existing high correlation between water (with some specific characteristics) and the snails presence and the disease.
