武汉市血吸虫病传播阻断后血吸虫病传播风险监测

Surveillance and risk assessment of schistosomiasis after transmission interruption in Wuhan

目的评估武汉市达到血吸虫病传播阻断后血吸虫病传播的潜在风险及风险因素特征,为防控策略的调整提供依据。方法分析并比较2018年和2019年武汉市筛选出的90个风险监测重点村钉螺、野粪、哨鼠、现场环境和人畜活动情况的监测结果,评估武汉市达到血吸虫病传播阻断后的血吸虫病传播的潜在风险及其特征。结果 2018年和2019年分别查螺118 335框和187 987框,活螺平均密度由0.012 2只/0.11 m^2下降至0.006 5只/0.11 m^2,降幅达46.72%。两年内均无阳性钉螺。两年监测期间均采集到牛粪和羊粪,但2019年采集到的野粪总数量显著下降,平均野粪密度较2018年减少89.80%。野粪检测结果显示均为阴性。未监测到阳性哨鼠。监测期间内监测地带部分区域仍有垂钓休闲和旅游等人群活动。监测期间内所有风险监测重点村风险评级均为Ⅲ级(最低风险)。结论武汉市达到血吸虫病传播阻断后血吸虫病传播风险处于较低水平,但钉螺、流动家畜野粪污染以及有螺地带人群活动等血吸虫病传播风险因素的作用不容忽视。需进一步加大风险监测力度,确保如期实现血吸虫病消除目标。

Objective To assess the transmission risk of schistosomiasis after transmission interruption in Wuhan City,and we provide scientific evidences for the planing of prevention and control strategies in this area.Methods Thesurveillance data(including Oncomelania hupensis snails, the wild feces, the S. japonicum infection in sentinel mice,environment conditions, and human and animal activities)of 90 schistosomiasis epidemic villages in Wuhan city in 2018 and 2019 were analyzed and compared, and the schistosomiasis endemic risks in the villages and the epidemiologicalcharacteristics were assessed.Results In 2018 and 2019, 118 335 and 187 987 frames were dissected, and the mean snaildensity decreased from 0.012 2/0.11 m^2 to 0.006 5/0.11 m^2, respectively, which decreased 46.72%. No schistosomiasis infectedsnails were found during the two surveillance years. Cow manure and sheep manure were collected during the two years ofmonitoring. The density of wild feces deeply decreased from 2018 to 2019, and the decreased rate was 89.80%. No infectionswere detected. There were no infected sentinel mice during the surveillance years. The human and animal activities weremainly fishing and touring. All of the environments were assessed as Grade Ⅲ(minimum risk) in the two years.ConclusionThere is a low risk of schistosomiasis transmission after transmission interruption in Wuhan City, while thepotential epidemic factors like snails, the contamination of field feces from migrating livestocks, as well as human activities onthe field with snails can not be ignored. Strengthened surveillance is essential for following goal in elimination of schistosomiasis in Wuhan City.