RESUMEN
Using the Kato Katz technique, 600 people living in Nakiwogo fishing village at Lake Victoria, Uganda, were examined for Schistosoma mansoni infection. The total population of this village was estimated between 1,000 and 1,500 mainly consisting of migrants from western Uganda. Of the 600 individuals in the study group, 328 people (54.7%) were found to be infected with S. mansoni. The geometric mean egg count was 422 eggs per gramme of stool. A survey of the snail intermediate hosts for S. mansoni and S. haematobium at Nakiwogo was carried out. The collected snails were tested for cercariae shedding. A significant decrease in the number of Biomphalaria choanomphala and Biomphalaria pfeifferi (52%) which both still shed cercariae and Bulinus tropicus (52.5%) could be observed. There was a lower none-significant decrease of 13.3% of the Bulinus globosus population. With a combined approach including community participation in control measures in the form of health education, sanitation, environmental management and chemotherapy, the prevalence of S. mansoni infection was reduced from 54.7% to 14.6% in the period of one year.