三水市钉螺分布特点、防制对策及远期效果观察

THE DISTRIBUTIVE FEATURES AND CONTROL STRATEGIES OF ONCOMELANIA SNAIL IN SANSHUI CITY

湖北钉螺是三水市日本血吸虫的中间宿主。根据调查，钉螺分布分为两型：草塘型分布于六泊草塘和迳口草塘．呈片状分布；州滩型分布于北江西岸，呈点状分布。防制对策是：①拦蓄山洪，②水利建设，包括建拦洪堤、河堤、挖排灌渠道、水库和电排站，变钉螺孳生地为可耕地，③开垦荒地，种植作物，④复杂的钉螺孳生场所采用沙埋、水淹、火烧和药杀灭螺等。通过上述防制措施，活钉螺数量逐步减少，１９７８年消灭了钉螺。螺情监测１５年，未有反复。

Oncomelania hupensis was the intermediate host of Schistosoma japonicum in Sanshui City. According to the investigation,the snail distribution were divided into two types. One was marshland type which distributed in Liupo Marsh and Jingkou Marsh with the snail distribution of stretch form.Another one was islet type which distributed along the west banks of North River with the snail distribution of spot appearance. The control strategies were: (1) retain the mountain flood, (2) water conservancy project including construction of embankment, dyke, irrigation cannals and drainage ditches, reservoirs and pumping stations, changing the snail breeding areas into the cultivatable land, (3) reclamation of wasteland and a new crop - growing, (4)burying with sand, inundating with water,burning and mollusciciding in the complicated snail ridden areas. After the treatment mentioned above the number of living snail was reduced year by year and the snail has been eradicated since 1978.