目的 分析浙江省2013-2015年钉螺分布及有螺原因，为有效控制钉螺提供科学依据。方法 收集2013-2015年浙江省血吸虫病螺情监测资料，并设计调查表格，对数据进行统计学分析。结果 调查累计发现钉螺面积130.88 hm2，螺点3 691个，未查到感染性钉螺；钉螺主要分布在沟渠、稻田、苗圃和水产养殖区4类环境，其中苗圃和水产养殖区钉螺面积所占比例逐年增高，2013-2015年分别占实际有螺面积的21.40%和19.68%、19.14%和16.15%、21.03%和16.28%。2013-2015年4类环境实有钉螺面积压缩率均为沟渠 > 稻田 > 苗圃 > 水产养殖区，差异有统计学意义（χ²=58 028.360、53 764.850、25 461.490，均P<0.05）；3年均以苗圃及水产养殖区的实有钉螺面积压缩率较低。结论 浙江省仍存在一定钉螺面积，苗圃及水产养殖区对钉螺孳生及扩散的影响日益加大，应加强监测，并因地制宜采取相应措施以减少钉螺面积。

Objective To analyze the environment of snail distribution and the reason of snail existence in Zhejiang province during 2013-2015, to provide scientific basis for effective control of snails. Methods The data of snail surveillance during 2013-2015 were collected and analyzed. And then a questionnaire was sent, to collect data and performed related statistical analysis. Results Small number of snails were found every year in an area of 130.88 hm2. There were 3 691 snail spots but no infected snails were found. The distribution of environment mainly were ditch, paddy, nursery and aquaculture area. The proportion of nursery and aquaculture area of snail increased year by year. Respectively, accounted for 21.40% and 19.68%, 19.14% and 16.15%, 21.03% and 16.28% of the actual snail area in 2013 to 2015. By analysis by SPSS 19.0 software, during 2013-2015, four actual snail areas of compression rate ranged ditch > paddy > nursery > aquaculture area, the difference was statistically significant(χ²=58 028.360, 53 764.850, and 25 461.490, P<0.05). The nursery and the aquaculture area environment of compression rate was low. Conclusion There are still certain areas of snail in Zhejiang province, effect of nursery and aquaculture area of reproduction and diffusion of snail was gradually increased. Nurseries and aquaculture areas with snail breeding and proliferation need to be monitored, local feasible measures should be considered to reduce snail areas.