Back ground. Schistosomiasis is one of the neglected tropical diseases and is prevalent in tropics. It causes morbidity and mortality in developing countries including Ethiopia. This study aimed to determine the prevalence of S. mansoni infection and associated risk factors among two schools of Guangua district, northwest Ethiopia. Methods. A cross-sectional study design was employed. Four hundred twenty-two participants were selected. Data was collected through observation and interview with structured questionnaire. Stool specimens were collected and examined using two-slide Kato-Katz method. The data were analyzed using SPSS version 23. Logistic regression was fitted for analysis. Variables with
p
value <0.25 in the univariate logistic regression analysis were entered into the multivariable logistic regression model. Those with <0.05 were identified as significantly associated risk factors. To assure the quality of the data, training was given for data collectors and supervisors, and the tools were pretested on 5% of the sample size. Results. 404 (95.7%) school children were enrolled in the study. The overall prevalence of S. mansoni was 12.6%. School children in the age group 5-9 years old (AOR (95% CI): 22.27 (3.70-134.01),
p
=
0.001
), age group 10-14 years old (AOR (95% CI): 4.58 (1.14-18.42),
p
=
0.032
), grade levels 5-8 (AOR (95% CL): 14.95 (4.297-52.03),
p
=
0.001
),who swim frequently (AOR (95% CI): 11.35 (2.33-55.33),
p
=
0.003
), and those who cultivate near the irrigation area (AOR (95% CI): 7.10 (2.31-21.80),
p
=
0.001
) were significantly associated with high risk of S. mansoni infection. Conclusion and Recommendation. From the finding of the current study, it can be concluded that the prevalence of Schistosoma mansoni in the study area is relatively high. Age of fourteen and younger years old, swimming in the river, and irrigation practice were the main risk factors of S. mansoni infection. Thus, therapeutic interventions as well as health education are desirable.
