Background: Schistosoma mansoni and soil-transmitted helminths (STH) are among the most prevalent and
highly neglected tropical diseases in Tanzania. However, little is known on the distribution of these infections in
rural settings, especially in the island areas on Lake Victoria. Identifying the local risk factors of S. mansoni and
soil-transmitted helminths is one step towards understanding their transmission patterns and will facilitate the
design of cost-effective intervention measures. The present study was therefore conducted to determine the
prevalence, intensity of infection and risk factors associated with S. mansoni and soil-transmitted helminth infections
among school children in Ukara Island.
Methods: This was a cross sectional study which enrolled 774 school children aged 4-15 years in 5 primary schools in
Ukara Island, North-Western Tanzania. Single stool samples were collected, processed using the Kato Katz technique
and examined for eggs of S. mansoni and geohelminths under a light microscope. A pre-tested questionnaire was used
to collect socio-demographic information.
Results: Overall, 494/773 (63.91%, 95% CI; 45.19-90.36) of the study participants were infected with S. mansoni and
the overall geometrical mean eggs per gram (GM-epg) of feaces were 323.41epg (95% CI: 281.09 – 372.11). The overall
prevalence of soil-transmitted helminth (STH) was 6.73% (n = 52/773, 95% CI = 4.39 – 10.32) with the most prevalent
species being hookworms, 5.69% (n = 44/773, 95% CI; 3.68 – 8.79). Location of school in the study villages (P < 0.0001),
parent occupation, fishing (P < 0.03) and reported involvement in fishing activities (P < 0.048) remained significantly
associated with the prevalence and intensity of S.mansoni infection.
Conclusion: Schistosoma mansoni infection is highly prevalent in the islands whereas the prevalence of
soil-transmitted helminths is low. The risk of infection with S. mansoni and the intensity of infection increased
along the shorelines of Lake Victoria. These findings call for the need to urgently implement integrated control
interventions, starting with targeted mass drug administration.