RESUMO
BACKGROUND: Schistosoma mansoni is one of the parasites with high public and medical importance in Ethiopia. However; information is scarce about S. mansoni epidemiology in people living with higher risk of infection in Jimma town. This study was designed to determine point prevalence; intensity and risk factors of S. mansoni infection among residents nearby three rivers of Jimma town and assess the rate of Biomphalaria species shading cercariae from January to April; 2007. METHODS: A cross-sectional study was conducted in communities residing nearby three rivers of Jimma town. Structured questionnaires were used to collect data on socio- demographic and behavioral risk factors. After physical examination; stool samples were collected from 517 study participants and processed with Kato-Katz technique for microscopic examination and quantification of egg load. Snails were collected for identification of Biomphalaria species and then checked for cercarial shading. RESULTS: The prevalence of S. mansoni was 26.3with intensity ranging 24 to 936 eggs per gram of stool. Participants in the age group 10-19 years; OR = 2.19 (95CI; 1.10 - 4.34); and those living near the Awetu River; OR = 2.67 (95CI; 1.06 - 6.75); had higher risk of S. mansoni infection. Moreover; water contact while crossing a river; OR = 3.77 (95CI; 1.79 - 7.95); and swimming; OR = 2.59 (95CI; 1.37 - 4.91; was significantly associated with infection. Biomphalaria snails collected from Chore and Awetu Rivers shaded higher rate of cercariae compared with Kito River. CONCLUSION: A moderate prevalence of S. mansoni infection was shown in the study population. Infection rate among the residents correlated with rate of cercarial shading Biomphalaria snails. Treatment of targeted groups; appropriate health education and environmental measures (e.g. snail control) are needed to improve the situation