山区水库常年灌溉对血吸虫病传播潜在影响的研究

目的 了解山区水库灌区引水灌溉对血吸虫病传播的潜在影响，为控制血吸虫病扩散提供科学依据。方法在泾县陈村水库总干渠自流灌溉区，选择一处引水干渠和一条灌溉斗渠为螺情观察点，每月进行系统抽样查螺，观察钉螺含血吸虫情况；并收集气象、水文资料和结合已有的基础理论，推算感染性钉螺被毛蚴攻击感染的季节以及感染性钉螺生存时期。结果干渠分别在6、7月份，斗渠分别在7、10月份发现感染性钉螺；6月份舍尾蚴之钉螺，其被血吸虫毛蚴攻击感染最近时间在上年9月份。7月中旬舍尾蚴之钉螺其被毛蚴攻击最近时间在当年5月份，10月中旬舍子胞蚴之钉螺其被攻击时间在当年8月份及此后。理论上在干渠坡滩，6～11月份有感染性钉螺存在，在斗渠感染性钉螺可常年存在。干渠虽常年有水，但淹滩主要在4、5月份及上年8、9月份，而斗渠较浅且常年有水。结论在总干渠自流灌溉区，干渠内感染性钉螺的形成及人畜感染的发生与水位变化有关；而在小型灌溉渠中，血吸虫传播可在大多数季节实现。

The potential impact of all year irrigation with resorvir water in montainous area on the transmission of schistosomiasis

Objective To understand the potential impact of irragation on the transimission of Schistosomiasis and provide information for controlling the disease in hilly irragation area of reservoir. Methods In the irrigation area of Chengcun Reservoir,a marshland in the main channel and a small ditch in the irrigation area were selected as obsrvation spots,where a systemic snail survey was conducted each month.The snails caught were detected for detection of Schistosoma.Data concerning climate and water level were collected.The infection of the snails by miracidia and the survival duration of the infected snails were estimated based on the present theory~(). Results Infected snails were detected in the main channel in June and July,the infected snails were discovered in the small ditch in July and October.The infected snail(with cercariae) found in June was estimated to be attacked by miracidia in last September,one(with cercariae) found in July to be attacked in May,and one(with daguhter cercariae) found in October to be challenged by miracidia in August or later.In theory,there were infected snails during the period from June to November in the main channel,while in the small ditch the infected snails could survive in the whole year.The snail habitats in the channel were submerged in April-May and last AugustSeptember;however the small ditch was not deep but it contained a little water all the year. Conclusion In the irrigation area,the development of infected snails in the main channel and infection of population and livestock were assiciated with high water level;meanwhile in the small irrigation ditch,these may take place during most seasons because of not deep ditch and always with some water.