2017年武汉市血吸虫病传播阻断和消除达标地区疫情评估

Evaluation on the endemic status of schistosomiasis in Wuhan area in 2017 following transmission interruption and elimination

目的对武汉市6个区的20个街(乡)进行血吸虫病传播阻断与消除达标考核。方法按照《血吸虫病控制和消除(GB15976-2015)》,对武汉市4个传播控制区的15个街(乡)和2个传播阻断区的5个街(乡)开展人群、家畜、螺情、档案资料考核以及现场钉螺调查。结果 2012~2016年15个传播阻断达标考核街血检223 361人,血检阳性数6 872人,共粪检6 839人,累计阳性290例,2012~2016年分别为137、116、26、11、0例,粪阳者全部进行流行病学调查,均为既往感染的历史遗留病人;累计存栏牛27 316头,粪检未发现阳性; 5年内均未发现阳性钉螺,活螺平均密度分别为0. 029、0. 018、0. 035、0. 024、0. 015只/0. 11m^2,抽样30个流行村,现场查螺活螺平均密度为0. 12只/0. 11m^2,未发现感染性钉螺;连续5年未发现当地感染的血吸虫病病人、病畜与感染性钉螺。5个消除达标考核街至少连续10年内无粪阳病人,为无牛区,共调查了8个流行村,现有钉螺面积为0,现场调查2 500框未查出钉螺。结论 2017年武汉市江夏、汉南、蔡甸、黄陂4区的15个街各项疫情指标已达血吸虫病传播阻断标准,武昌、武汉开发区2区的5个街已达血吸虫病消除标准,为下一步全区达标提供了充分依据。

Objective To assess the endemic status of schistosomiasis in Wuhan area（ including 20 community blocks and towns under 6 administrative districts） following transmission interruption and elimination. Methods Full survey was conducted in population, livestock, snail prevalence through examining the reported data and field study in the areas described above, according to the criteria specified in Control and Elimination of Schistosomiasis （GB15976 -2015）. Results Between 2012 and 2016, a total of 223 361 residents in 15 community blocks and towns that reached the criteria of transmission interruption received indirect hemagglutination （IHA） test, and positive cases were found in 6 872. Stool sample test performed in 6 839 residents revealed positive results in 290. Infected cases of schistosomiasis were 137, 116, 26, 11 and 0, respectively from 2012 to 2016. Patients with positive stool were undergone epidemiological study, and the results showed that they were totally historical infection. Stool detected in a total of 27 316 cattle on hand showed no infection. Infected snails were free in the past 5 years. The average density of living snails were 0. 029, 0. 018, 0. 035, 0. 024 and 0. 015 heads/0.11m^2, respectively from 2012 through 2016. Thirty villages with snail prevalence were sampled, field study indicated that average density of the snail was 0.12 heads/0.11 m^2. Infected snails were free. Local infection was absent with population, livestock and snails in the past 5 years. No positive stool samples were found in population in the 5 areas（ cattle being free） that reached the elimination criteria for 10 consecutive years. Survey at the 2 500 frames sampled in the 8 villages with historical snail prevalence showed that the areas with snail were zero. Conclusion Our findings suggest that 15 community blocks under administrative Jiangxia, Caidian, Hannan and Huangpi districts reached the criteria of schistosomiasis transmission interruption, and another 5 community blocks under Wuchang and economic development zone administration arrived at the criteria of schistosomiasis elimination. This achievement may lay a foundation for planning our policies.