The initial epidemiological studies in the low endemicity schistosomiasis area in Esteio, Rio Grande do Sul, the southernmost Brazilian state, 1997 to 2000.

Nor Biomphalaria glabrata neither Schistosoma mansoni were reported from Rio Grande do Sul, the southernmost Brazilian state before 1997. Their detection next to the Sinos River, Esteio, confirmed predictions of schistosomiasis expansion to the south. Parasitological examinations both in snails and fecal samples from the human population were performed from 1997 to 2000.