张家港市改水对肠道传染病的控制作用与效益评估

Evaluation of Control Effects of Improvement of Drinking Water Supply on Intestinal Infectious Diseases and its Benefits in Zhangjiagang

为评估张家港市改水对肠道传染病的控制作用和经济效益，用流行病学与有关经济学方法对１９８７１９９８ 年全市改水的投入、改水前后水质与供水量变化、改水受益人口增加与有关介水传染病（ 肝炎、痢疾和伤寒） 逐年下降情况、改水对预防这些疾病产生的经济效益作了调查分析。结果表明：至１９９８ 年改水总投入达１１ １４４ 万元，改水后饮用水源与出厂水水质均有明显改善，１２ 个镇自来水供水从无到有，平均供水量增加３ 倍以上，改水受益与介水传染病发病率呈高度负相关关系，改水对防病产生的直接、间接经济效益已达到改水总投资的９８－５ ％ 。作者认为在提高自来水普及率的同时。

To evaluate the control effects of improvement of drinking water supply on intestinal infectious diseases and its economic benefits ,the following situations,such as the total investment in the improvement of drinking water supply,the variances of water qualities and output of all of the water plants before and after the improvement,the relationship between the increase of annual benefited population and the gradually reduced annual incidence rates of water borne infectious diseases(hepatitis,dysentery and typhoid),the economic benefits contributed by the improvement of water supply,which had prevented population from those water borne infectious diseases,were analysed with epidemiological and related economic methods in Zhangjiagang during 1987~1998.The results showed that the total investment on the improvement of water supply was 111.44 million yuan by the end of 1998.The qualities of source water and treated water revealed significant improvement after the water supply improvement.New water plants were built in 12 towns,which had no tap water in the past.The average quantities of water supply increased 3 times more than those before.The annual benefited rates of population and the annual incidence rates of water borne infectious diseases presented very significant negative correlation.The direct and indirect economic benefit of diseases prevention caused by water supply improvement reached to 98.5% of total investment on improvement.The author realized that the coverage rates of tap water should be increased,in the meantime the management of tap water disinfection should be more strengthened.