Table 1. 2006 World Health Organization categorization of communities at risk for schistosomiasis [16].

Community category	Prevalence among school-aged children:
I. High-risk community	≥50% by parasitological methods (intestinal and urogenital schistosomiasis), or ≥30% by questionnaire for visible hematuria (urogenital schistosomiasis)
II. Moderate-risk community	≥10% but <50% by parasitological methods (intestinal and urogenital schistosomiasis), or <30% by questionnaire for visible hematuria (urogenital schistosomiasis)
III. Low-risk community	<10% by parasitological methods (intestinal and urogenital schistosomiasis)