南水北调东线一期工程血吸虫病监测预警研究Ⅱ钉螺和血吸虫病监测

Study on surveillance and early-warning system of schistosomiasis in first phase of east route of the South-to-North Water Diversion Project Ⅱ Surveillance of Oncomelania hupensis and schistosomiasis

目的了解南水北调东线一期工程区螺情和血吸虫病病情现状,为建立该工程血吸虫病监测预警体系提供依据。方法选择南水北调东线水源区、宝应及金宝航道以南的输水河道及影响区为监测范围,采用常规法进行钉螺监测和人畜血吸虫病监测调查,同时选择里运河高邮界首渡口、金宝航道和宜陵河口为监测点,采用"网捞法"和"稻草帘诱螺法"进行水体钉螺监测。结果 2006-2009年南水北调东线钉螺面积70%以上分布在水源区,并呈下降趋势;17%～28%分布在相邻的湖区;输水河道钉螺面积占0.36%以下,分布于原历史有螺区域。3个监测点网捞法打捞漂浮物2 824kg,未发现钉螺;投放稻草帘880块,在宜陵河口诱获钉螺456只;居民查病血吸虫阳性率由0.19%下降至0,未发现病畜。结论南水北调东线一期工程区的血吸虫病疫情已得到有效控制,输水河道钉螺未发生北移扩散,主要风险是水源区及相邻的湖区尚有较多钉螺孳生,仍需对工程区加强监测和控制。

Objective To understand the present situation of distribution of Oncomelania hupensis and prevalence of schistosomiasis in the east route of the South-to-North Water Diversion Project.MethodsA surveillance range including the water source areas,the water delivery areas and the affected areas in the south of Baoying County and Jinbao Channel were chosed in the east route of the South-to-North Water Diversion Project.The conventional methods were used for the surveillance of snails and schistosomiasis.The methods of net salvage and attracting snails with rice straw curtains were used for survey of snails under water in the surveillance sites of Gaoyou Jieshou Ferry,Jinbao Channel and Estuary of Yiling River.ResultsMore than 70% of the snail areas were distributed in the water source areas,17%-28% distributed in the lake areas,and those in the water delivery channel were less than 0.36% in the east route of the South-to-North Water Diversion Project area from 2006 to 2009.The snail area of the water source areas showed a downtrend,but the area in the lake areas had no obvious change.The snail habitat still located in the former place in the water delivery channel.A total of 2 824 kg flotage were refloated and 880 pieces of rice straw curtains were placed in the 3 surveillance sites.The results showed that there were no snails in the flotage.The rice straw curtains attracted 456 snails in the estuary of Yiling River.At the same time,the positive rates of schistosomiasis in residents dropped from 0.19% to