Resumo:
A geographic information system was constructed using maps of regional environmental features, Schistosoma
mansoni prevalence in 30 representative municipalities, and snail distribution in Bahia, Brazil to study the
spatial and temporal dynamics of infection and to identify environmental factors that influence the distribution of
schistosomiasis. Results indicate that population density and the duration of annual dry period are the most important
determinants of prevalence of schistosomiasis in the areas selected for study. Maximum rainfall, total precipitation
during three consecutive months, annual maximum or minimum temperatures, and diurnal temperature difference
were not shown to be significant factors influencing S. mansoni prevalence in local populations or distribution of
snail hosts. Prevalence of the disease was highest in the coastal areas of the state. Higher prevalence tended to occur
in areas with latossolo soil type and transitional vegetation.
