中国血吸虫病流行现状分析

The current status of schistosomiasis epidemics in China

目的 分析近5年来中国血吸虫病流行趋势及疫情变化的特点。方法 收集血吸虫病流行历史资料及近年流行区疫情报告资料,比较分析1998年后全国血吸虫病流行趋势和疫情回升特点。结果 2003年底报告资料显示,与建国初期相比,全国流行省、县、乡镇分别减少了42％、40％和53％;血吸虫病估计病例数较建国初期减少了92.74％;钉螺面积减少了73.56％。但全国推算慢性血吸虫病例数徘徊在80万左右,急性感染报告数以年平均25％上升;1998年以来钉螺面积净增加31321.5万m^2,全国7省20个纵向监测点内,30％、70％和35％监测点的人群、耕牛和钉螺的感染率分别出现上升趋势。湖区5省中有38个达到血吸虫病传播控制和传播阻断标准县(市、区)疫情分别出现了明显的回升,湖南省6个非疫区(株洲市3个、长沙市2个、桃源县1个)新发现钉螺,长沙市桔子洲头等I6个洲滩均有钉螺,并发生急性感染;已阻断传播地区如上海、浙江、福建等省市也发现大面积钉螺。长江中下游沿江的大中城市相继发现感染性钉螺和新发病例。结论 近年来长江中下游地区局部血吸虫病流行区疫情回升明显,回升原因有环境生态变化、社会经济变化及预防控制力度变化等因素的影响。

Objective To analyze the change of tendency on schistosomiasis epidemics in China in the last 5 years. Methods Data on schistosomiasis epidemics in the history and particularly in the last 5 years were collected. Tendency and the re-emerging status after 1998 were analyzed. Results Data in 2003 showed that in 42%, 40% and 53% of the provinces, counties and townships with epidemics, the transmission of the disease has been interrupted or controlled. The number of estimated patients of schistosomiasis and areas with snails were also reduced by 92. 74% and 73. 56%, in 2003. The annual estimated number of chronic cases was around 800 000 and 31 321. 5 hectare of snail infested areas were newly identified in recent 5 years. Among 20 national villages under longitudinal surveillance. 30%, 70% and 35% of the villages were presented a tendency of increase in the rates of human infection. bovine infection and Oncomelania snails infection, respectively. A total of 38 counties from 7 provinces have re- emerged in schistosomiasis transmission after those counties having reached criteria of transmission under control or interrupted. In 6 non-endemic counties, snails were presented, and 16 marshlands in Xan river were found with appearance of acute cases of schistosomiasis. More snail infested areas were found in Shanghai, Zhejiang, and Fujian. Both snail infested areas and newly infeeted cases were occurred in urban areas along the Yangtze River. Conclusion The tendency of increase was presented in focal areas along the Yangtze River, due to changes of environmental, ecological, societal and economic status, as well as on the forces of control.