CHRONIC CARRIERS OF HEPATITIS-B SURFACE-ANTIGEN IN AN ENDEMIC AREA FOR SCHISTOSOMIASIS-MANSONI IN BRAZIL

Data on the association of schistosomiasis and hepatitis B in field-ba sed studies are scarce. Two areas have been selected for this study: i ) Queixadinha, endemic for schistosomiasis, with a population of 693 i ndividuals, and ii) Capao, a control non-endemic area, with 515 inhabi tants. Sera of all individuals in both areas were tested for hepatitis B infection, yearly, from 1994 to 1997. in the first;st area hepatiti s B was found in 32.1% of children tip to one year old and reached a p eak of 68.7% in the age range of 15 to 19 years. In the control area t he prevalence of hepatitis B was under 5% up to 19 years of age and th e highest prevalence was observed in adults over 45. HBsAg was detecte d in 9.4% of the individuals living in the endemic al ea for schistoso miasis and in 1.4% of the controls (OR=4.98; 95%CI=3.7-6.7). The index of chronicity of HBsAg was not statistically different in the studied ar-eas (8.1% x 7.3%; OR=1.09; 95%CI=0.42-3.03), nor was it different for people with and without schistosomiasis in Queixadinha (8.7% x 7.0 %). We conclude that the Schistosoma mansoni infection has not altered the course of hepatitis B in the studied area.