Abstract:

The historical Oncomelania snail environments discovered since 1976 were surveyed in Changshu City，Jiangsu Province. There were 425 foci of historical snail environments that were discovered in 16 towns，the snail area was 124 893 m2 . The transformation rates of historical snail environments and of the snail area were 76.71% and 86.92%，respectively. The transfor? mation rates of the ditches，the ponds and the land were 98.17%，97.93%，and 95.04%，respectively，but the transformation rate of river channels was only 28.23%. We still need to strengthen the environmental transformation of historical snail river channels.

Key words: Schistosomiasis； Oncomelania snail；Changshu City

摘要：

对常熟市1976年以来历史有螺环境进行调查。全市16个镇查出有螺环境425个， 有螺面积124 893 m2 ， 历史有螺环境和有螺面积改造率达76.71%和86.92%。其中沟渠、 池塘、 田地的改造率分别为98.17%、 97.93%、 95.04%， 河道的环境改造率为28.23%。提示需积极开展对历史有螺河道的环境改造。

关键词: 血吸虫病； 钉螺； 常熟市