Schistosomiasis, a chronic parasitic disease is caused by a blood fluke (Schistosoma). 200 million people are infected worldwide, 85% in sub-Saharan Africa. In Kenya coastal region and irrigation schemes are endemic. Mwea irrigation scheme is endemic with 47% prevalence. Close proximity of Kagio area to the irrigation scheme offers labor opportunities to the population including school children posing a transmission threat. This study investigated Schistosoma mansoni infections among school children aged 8-15 years. Kagio and Kang’aru schools (Kagio area) and Kandongu (Mwea irrigation scheme) were selected. 322 pupils were tested for the presence of S. mansoni eggs by direct wet smears and Karto Katz. 263 questionnaires were administered to pupils from Kagio and Kang’aru schools. Data was... analysed using Chi square and t-test statistics. Results showed that 7.2% of pupils from Kagio area had Schistosoma mansoni compared to 22% sampled from Mwea irrigation scheme. Mean number of eggs was 56 epg and 104 epg for the pupils who had light infection and those with moderate infection respectively. No pupils had heavy infestation. Pupils from Kagio area who worked in the farms in Mwea irrigation scheme were more prone to infection. 7.9% of those infected worked in rice paddies compared to 4% of infected pupils who did not. There was a significant relationship between labor migration and occurrence of Schistosoma mansoni infection among school children in Kagio area (x2=1.267; df=1; P=0.2604). There was no significant difference in infection rates between pupils from Kagio and Mwea areas (t=5.33, cl=95%, df=1, P=0.118). Schistosoma mansoni was present in both endemic and non-endemic areas. Labor migration was a significant transmission risk factor. The results indicate a need for the policymakers to institute programs that are designed to eliminate or minimize child labor migration from non-endemic to endemic areas as a way of preventing spread of Schistosoma mansoni, regular testing and treatment of the entire population and extend control interventions to neighboring non endemic area.