A cross-sectional survey on schistosomiasis was done in Comercinho (Minas Gerais State, Brazil), a town with 1474 inhabitants. Quantitative stool egg count (KATOKATZ technique) and clinical examination were done on 90 and 80% of the total population, respectively. Signs and symptoms presented by patients with different S. mansoni egg counts were compared and the alterations of the liver size and consistency were related to higher egg excretion (> 1000/g feces) in 2-14 year age group, but not in older patients. The following clinical signs were more frequent in patients that excreted S. mansoni eggs when compared to the control group (no S. mansoni eggs in the feces, absence of previous specific treatment and negative intradermal test): a) in patients from 2-14 years of age, blood in the feces, palpable liver, hardening of the liver and enlargement of the liver right and left lobes; b) in above 15 year old individuals, palpable liver; c) in both age groups, the splenomegalies were exclusively related to S. mansoni infection.