Fig. 4

Schistosoma mansoni infection prevalence and intensity. The prevalence of S. mansoni was stratified by gender (A), age groups (B), and by communities where schools were located (C). The S. mansoni infection intensity was classified as light infection (1–99 eggs/gram), moderate infection (100–399 eggs/gram) and heavy infection (≥ 400 eggs/gram) (D). The bar chart represents the percentage (%) prevalence with 95% confidence intervals (i.e., error bars). The dark (black) bars are the uninfected group and the light bars represent the infected group