中文摘要：

目的探讨钉螺人工群体感染血吸虫的优化时间。方法在实验室条件下,采用日本血吸虫毛蚴分别感染钉螺2、3、4 h 3组,观察感染60-120 d后各组钉螺死亡率、钉螺感染率及尾蚴获得量,分析各组3个指标的差异,以钉螺死亡率相对低、钉螺感染率和尾蚴获得量相对高的钉螺感染时间为最优时间。结果3 h感染组60 d的钉螺感染率显著高于其他组（P〈0.05）,钉螺死亡率低于其他组（P〈0.05）,60-120 d的尾蚴获得量显著高于2 h感染组（P〈0.05）,与4 h感染组差异无统计学意义（P〉0.05）。结论实验室条件下,血吸虫毛蚴人工群体感染钉螺3 h为相对优化的感染时间。

英文摘要：

Objective To explore the optimizational time of artificial population schistosome infected Oncomelania hupensis snails. Methods Under laboratory conditions,the snails were infected with the miracidia of Schistosoma japonicum for 2 h,3 h and 4 h respectively,and the death rates and the infection rates of the snails,and the quantities of cercariae of each group were observed 60-120 d after the infection,and all the data observed were analyzed to get the optimizational time of artificial population schistosome infected snails. Results Of the 3 h group,the snail infection rate was the highest and the mortality was the lowest among the 3 groups（P0.05）. The average number of cercariae of the 3 h group was higher than that of the 2 h group（P0.05）, while there was no statistical difference between the 3 h group and the 4h group（P0.05）. Conclusion Under laboratory conditions,the optimizational time is 3 h in artificial population schistosome infected O. hupensis snails.