太湖平原城市化背景下残存钉螺复燃因素及对策研究

Study on Control Strategy and Recrudescence Factors of Snails during Urbanization in Tai Lake Plain

[目的]探讨城市化背景下残存钉螺复燃因素及对策。[方法]2007年7月至2010年6月,收集太湖平原及无锡市血吸虫病相关资料及观察有关现场进行分析。[结果]1981年调查无锡市锡澄运河东侧12个乡(镇)血吸虫病流行村血吸虫病患病率,Ⅰ线为7.09%,Ⅱ线为3.93%,Ⅲ线为17.39%,Ⅳ线为36.46%,提示血吸虫病患病率,下游>上游,低洼处>高亢处。2010年调查无锡市东郊3个乡、12个村中,距离市中心6.5km的4个村,历史有螺环境彻底改变,已不具备钉螺孳生条件(Ⅰ类环境);距离市中心12.5 km的4个村,历史有螺环境中Ⅰ类环境占43.97%,未进行改造或改造后又恢复为原始状态(Ⅳ类环境)占36.71%;距离市中心17.05 km的4个村,历史有螺环境中,钉螺孳生条件未能消除,有可能残留钉螺(Ⅲ类环境)占78.83%。实验观察结果,水样中溶氧量内滩池高于闾江河,总硬度、硫酸盐、氨氮和氯化物内滩池低于闾江河(P<0.01或<0.05);土样的有机质与镁离子含量,均为闾江河低于内滩池(P<0.05或<0.01);钉螺100 d存活率为67.00%,其中A箱、B箱、C箱、D箱分别为59.67%、62.00%、68.33%、78.00%(P<0.01)。[结论]太湖平原城市化背景下残存钉螺复燃与水系的变化及水质有一定关系。

[Objective] To explore the control strategy and recrudescence factors of snails during urbanization.[Methods]In July 2007 to June 2010,the information of Schistosomiasis was collected and some fields were observed in Wuxi city and Tai lake plain.[Results]In 1981,the first line of Schistosomiasis prevalence of 12 towns endemic village east of Xicheng Canal in Wuxi City was 7.09%,the second line was 3.93%,the third line was 17.39%,the fourth line was 36.46%,the lower reaches were greater than the upper reaches,the low-lying was greater than high-pitched.2010,there were 12 villages in the eastern suburbs of Wuxi city,the history snails environment was completely changed,the snails breeding conditions were destroyed（Class I environment） in 4 villages that were 6.5 km from the center of city;the Class I environment percentage was 43.97%,the environment that was not changed or restored to original state after being changed（Class IV environment）percentage was 36.71% in 4 villages that were 12.5 km from the center of city;the environment that the snails breeding conditions was not destroyed,there may be residual snails（Ⅲ Class environment） percentage was 78.83% in 4 villages that were 17.05 km from the center of city.Dissolved oxygen of water samples within the inside beach pool was above than Lvjiang river,total hardness,sulfate,ammonia and chloride within the Inside beach pool was lower than the Lvjiang River（P0.01 or 0.05）.The organic matter and magnesium ions of soil samples within the inside beach pool were higher Lv River（P0.05 or 0.01）.The snail survival of 100 days was 67.00%,of which A box,B box,C box,D box were 59.67%,62.00%,68.33%,78.00%（P0.01）.[Conclusion]There is a certain relationship between resurgence of surviving snails and the change of river systems and water quality during urbanization in Tai lake plain.