山丘型血吸虫病流行区小环境改造的费用—效果分析

EVALUATION OF COST-EFFECT OF SMALL ENVIRONMENT MANAGEMENT IN HILLYTYPE ENDEMIC REGIONS FOR SCHISTOSOMIASIS CONTROL

山丘型血吸虫病流行区因地制宜进行沟渠硬化、沼泽地改塘等小环境改造措施后,钉螺面积减少了66.16％,活螺密度、活螺框出现率分别下降了76.54％和76.13％,阳性螺密度下降了100％;居民血吸病患病率略有下降,14岁以下人群感染率为0,无急性感染发生。而实施药物灭螺的对照组9年来钉螺面积仅下降了27.62％,活螺密度及活螺框出现率分别上升了26.35％和151.01％,是小环境改造点的9.84倍和11.13倍,同时居民血吸虫病患病率较1987年上升了37.44％,14岁以下人群感染率为1.21％,并有零星急性感染病例发生。小环境改造一次性投资费用高于药物灭螺,但与农田水利相结合的小环境改造措施能够产生一定的间接经济效益,因此远期效果仍将优于药物灭螺。

In a hilly type endemic area, the environmental management measures against snail were taken to control schistosomiasis. The results showed that the snail areas reducedby 66.26%, density of snail, percentage of frames with living snail reduced by 76.54% and 76.13% respectively, density of positive snail reduced by 100%, The prevalence rate of schistosomiasis decreased slightly,no case among the population below 14 years old, and no acute schistosomiasis occured, which had highly significant difference compared with control area where only taken mollusicide measure. Although the first investment of environmental management was higher than that of mollusicide, the cost for eliminating 100m^2 snail areas and cost of each person benefitted was 6.94 times and 11.39 times higher than that of moliuscide respectively, and, it could also produce indirect economic benefit, the long term effect would still better.