安乡县淘汰散放牛控制血吸虫病传播效果

目的评价以传染源控制为主的血吸虫病综合防治策略在湖沼型流行区的实施效果。方法在湖南安乡县的2个邻近乡（镇）各选择7个行政村为试点村和对照村,每年均开展人畜化疗和易感地带灭螺等常规血防措施。2005年,在试点村淘汰所有存栏牛和羊,并辅以封洲禁牧、以机代牛、改水改厕等巩固措施。2005-2011年采取统一的调查方法对人群和钉螺感染情况进行跟踪观测。结果试点村人群感染率在干预后的第3年降至1%以下,垸外无感染螺。对照村第4年后感染率仍徘徊在2%～3%。淘汰牛等传染源控制措施使试点村近50%的人口免于感染或再感染血吸虫。结论淘汰或杜绝散放牛是湖沼型血吸虫病流行区传染源控制策略的核心技术,有助于该类疫区早日实现控制和阻断血吸虫病传播的远期目标。

Evaluation of schistosomiasis control effect of buffalo removal in Anxiang County

Objective To evaluate the effect of a comprehensive schistosomiasis control strategy based on buffalo removal in a lake and marshland region.Methods A community intervention trial was carried out in seven pilot villages and seven control villages along Dongting Lake in Anxiang County,Hunan Province.Besides annual routine control measures such as synchronous chemotherapy,molluscicidal spray and health education,all buffaloes and sheep were killed or removed from the pilot areas in 2005,of which the effect was strengthened by other supporting measures such as replacing bovines by agricultural machines,isolating meadows and prohibiting pastures,supplying safe water,and building sanitary lavatories or methane pits.Schistosoma japonicum infection in humans or Oncomelania snails was observed and followed up to the spring of 2011.Results Three years after the intervention,the infection rates in humans decreased to below 1% with no infected snails found outside the embankment in the pilot villages,but the infection rates still ranged between 2% and 3% in the control villages 4 years after the intervention.The comprehensive measures centered on buffalo removal exempted about 50% of the population from the infection in pilot villages.Conclusion Buffalo removal is the key element of comprehensive control strategy which could accelerate the control process and promote the elimination of schistosomiasis in lake and marshland regions along the Yangtze River.