Analysis of surveillance results of transmission-blocked schistosomiasis in Hangzhou

Objective The study was conducted to investigate the epidemic situation in Hangzhou ensued from the blocking of transmission of schistosomiasis, providing evidence for the development of control strategies in future. Methods Surveillance of schistosomiasis and conches was conducted in accordance with the Consolidation Surveillance Programs after the Eradication of Schistosomiasis in Zhejiang Province. Results Lately infected local residents or livestock were not found in the surveillance. However, a total of 12 imported cases were found. An area of 117 853 218 m2 of water snails were accumulatively examined, with 15 436 snails being dissected and 152 100 m2 of snails exterminated. Positive snail carriers were not detected. Conclusion The schistosomiasis epidemic in Hangzhou is in stability without local cases. However, importation of involved cases is occasionally detected. Water snails still living in parts of counties constitute a threat of epidemic rebounds. Therefore, historical water-snail dwelling areas that are not environmentally reformed and the peripheral should be frequently examined for snails with extermination delivered. Flow of population from epidemic areas should be monitored.