Abstract:

Objective To specify the trends of endemic situation among twenty one national surveillance sites for schistosomiasis from 2000 to 2004. Methods According to the national surveillance protocol, longitudinal surveillance on endemic situation of schistosomiasis was carried out at twenty-one sites since 2000. Results The infection rate of Schistosoma japonicum declined in six of the twenty-one surveillance sites. The density of living snails and of infected snails decreased in two sites but not well controlled in most other sites. The prevalence in cattle fluctuated yearly in most sites and maintained at a relatively high level. During the surveillance period, acute cases were found annually and the number of advanced patients did not increase significantly. No new case and infected snails were found in Jinshan, Shanghai, since 2000, where transmission of schistosomiasis was interrupted two decades ago. Conclusion Routine control strategies such as selective chemotherapy combined with livestock chemotherapy, snail control in risk areas have a positive impact on the control of schistosomiasis. However, these strategies should be lasted for longer time and the surveillance on snails and cattle should be continued.

Key words: Schistosomiasis, Endemic situation, Surveillance