三峡建坝后血吸虫病传播危险因素研究Ⅰ库区生态环境变化对钉螺孳生可能性研究

目的探讨三峡建坝后库区生态环境改变对钉螺在库区生长、繁殖的可能性。方法收集并利用三峡库区有关生态环境及血吸虫病相关研究资料,开展实验室和现场模拟环境钉螺生存繁殖实验及库区现场调查。结果实验室结果表明,模拟的库区土壤环境适宜钉螺生存,且有幼螺孵出,但较现场存活率为低。现场模拟试验结果显示,钉螺存活率宜昌比万州和江津的观测点相对较低(P均<0.05)。土壤湿度与钉螺存活率存在相关性(r=0.3712,P=0.002),土壤pH值、有机质等指标都对钉螺孳生有一定影响。结论在库区模拟的灌溉沟渠和淤积洲滩环境条件下,钉螺可以生存繁殖。应加强对库区潜在钉螺孳生环境的监测,以防钉螺向库区扩散。

Risk factors of schistosomiasis transmission after Three Gorges Construction Ⅰ Possibility of snail breeding with ecological changes in Three Gorges Reservoir areas

Objective To explore the possibility on the growth, development, reproduction of Oncomelania snails with the ecological changes after the Three Gorges construction. Methods The relevant data of ecological environment and schistosomiasis in the Three Gorges Reservoir areas (TGRA) were collected, and the simulated experiments were carried out to observe the snail survival and reproduction in laboratory and the field. Meanwhile, the field survey was performed. Results The laboratory experiments showed that the soil was suitable for Oncomelania snails in TGRA. The survival rate of the snails in Yichang site was relatively lower than those in Wanzhou and Jiangjin sites in the field (P<0.05 ). The survival rate of the snails had a correlation with the humidity of soil (r=0.3712,P=0.002). The indexes of soil on pH, organic substance and so on had a certain influence for the snail survival. Conclusions Under the simulated condition of irrigation canal and alluvial shoal in TGRA, the snail could survive and reproduce quite well. Thereby, it is necessary to strengthen surveillance of the potential snail habitats in TGRA to prevent the snail spreading from other areas.