Data on the association of schistosomiasis and hepatitis B in
field-based studies are scarce. Two areas have been selected for this
study: i) Queixadinha, endemic for schistosomiasis, with a population
of 693 individuals, and ii) Capão, a control non-endemic area,
with 515 inhabitants. Sera of all individuals in both areas were
tested for hepatitis B infection, yearly, from 1994 to 1997. In the
first area hepatitis B was found in 32.1% of children up to one year
old and reached a peak of 68.7% in the age range of 15 to 19 years. In
the control area the prevalence of hepatitis B was under 5% up to 19
years of age and the highest prevalence was observed in adults over
45. HBsAg was detected in 9.4% of the individuals living in the
endemic area for schistosomiasis 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 areas (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.
