本文报道了湖沼地区血吸虫易感季节（４～６月）１５天间隔口服青蒿琥酯预防日本血吸虫感染的效果。结果服药组的粪检阳性率为２．６５％，ＥＰＧ为６．５±６．３５；服安慰剂组为粪检阳性率８．３３％，ＥＰＧ为８１．３１±９．５４；表明血吸虫病流行地区在易感季节每半个月口服青蒿琥酯１次，对疫区人群有较好的防护作用 This paper reports the effect of oral administration of artesunate on Schistosoma japonicum infection in the lakes and marshes at the 15-day interval of schistosomiasis susceptibility season (April-June). Results The positive rate of stool examination in medication group was 2.65% and the EPG was 6.5 ± 6.35. The positive rate of stool test in placebo group was 8.33% and the EPG was 81.31 ± 9.54. Disease endemic areas in the susceptible season every two months of oral artesunate once, for the affected area have a better protective effect