Control efficacy on prevalence rate in the study areas according to age and treatment strategy.

MT2, mass treatment every 2 year; MT1, mass treatment every year; ST1, selective treatment every year; ST1R, selective treatment and reservoir control every year; ST6M, selective treatment every 6 month; ST2-mod, selective treatment every 2 year; ST1-mod, selective treatment every year.1Age specific CS prevalence rate (PR) for 1 year.2p-value for group difference among the specific age groups with each strategy in heavy endemic areas.