长江洪水中日本血吸虫尾蚴分布及其对人群血吸虫感染的影响

Distribution of Schistosoma japonicum cercaria in Yangtz river during the flood period and it's effect on the human infection

目的阐明长江洪水中日本血吸虫尾蚴分布及其对人群血吸虫感染的影响。方法采用哨鼠测定法,观察洪水中血吸虫尾蚴分布及其漂移扩散范围。通过对距阳性螺地带不同距离人群血吸虫感染情况,分析水体尾蚴分布对人群血吸虫感染的影响。结果长江洪水中血吸虫尾蚴主要分布在距阳性螺点2000m以内的区域,人群血吸虫感染率与距阳性螺点的距离呈负相关关系(rs=-0.976,P<0.01),居住在距阳性螺1000m以内者人群血吸虫感染率显著高于1000m以外人群(χ2=6.145,P=0.013)。结论长江洪水中尾蚴分布及人群血吸虫率与距阳性螺点的距离呈负相关关系。

Objective To explore the distribution of S. japonicum cercaria in Yangtse River during the flood period and its effect on the human infection. Methods The distribution of S. japonica cercaria in flood and its diffusive range were observed using sentinel mice exposure test. By surveying the infective stares among the local residents in different distance, the influence of the cercarial distribution in water on the human infection was analyzed. Results The cercaria mainly distributed in the areas 2000m away from the place with positive snails. Negative correlation was seen between the human infection rate and the distance from the place with positive snails. The infection rate among the population in the area less than 1000m from infected snail areas was significantly higher than those in the areas over 1000m from the place with positive snails. Conclusion Negative correlations was found between the cercarial density in the flood of the Yangtze River and the distance from the place with positive snails, and the status was same between the people＇s infection rate and the distance from the place with positive snails.