2005—2019年云南省勐腊县流行性乙型脑炎流行特征分析

Analysis on epidemiological characteristics of Japanese encephalitis in Mengla County of Yunnan from 2005 to 2019

目的分析2005—2019年勐腊县流行性乙型脑炎流行特征,为科学防控乙脑提供依据。方法收集中国疾病预防控制中心传染病报告信息管理系统和乙脑监测信息报告管理系统中2005—2019年勐腊县乙脑确诊病例资料,进行描述、比较和分析。结果2005—2019年勐腊县共报告乙脑111例,死亡13例,平均发病率2.66/10万,病死率11.71%,发病率逐年呈波动性下降趋势(χ2=16.676,P<0.001)。乙脑发病呈现明显季节性,92.8%的病例集中在5—7月,6月为发病高峰;勐腊县14个乡镇(农场)中有13个乡镇(农场)有乙脑报告。乙脑患者男女性别比1.27∶1。以散居儿童(44.14%)和学生(27.03%)为主,乙脑发病年龄中位数为7岁,以小于15岁的儿童为主,其中0~4岁的病例32例,占28.83%;5~14岁的病例50例,占45.05%。2017年和2019年非儿童乙脑病例比例均超过儿童病例。乙脑从发病到确诊时间的中位数为5 d,临床诊断病例66例(59.46%),实验室确诊病例45例(40.54%)。96.40%的乙脑病例(107/111)无免疫史或免疫史不详。结论应采取包括提高乙脑疫苗免疫覆盖率在内的综合措施,进一步降低乙脑发病率和死亡率。

Objective To analyze the epidemic characteristics of Japanese encephalitis(JE)in Mengla County from 2005 to 2019 for scientific prevention and control of Japanese encephalitis.Methods The confirmed JE cases that occurred during 2005-2019 were collected from infectious disease reporting information management system and Japanese encephalitis surveillance information reporting management system of Chinese Center for Disease Control and Prevention,for description,comparison and analysis.Results There were 111 JE cases in Mengla County reported from 2005 to 2019,and 13 cases had died.The average annual incidence was 2.66/100000,and the fatality rate was 11.71%.The incidence showed a fluctuating downward trend year by year(χ2=16.676,P<0.001).92.8%of the JE cases were concentrated from May to July,with a peak in June.The cases were reported in 13 of 14 towns and farms.The sex ratio of male to female in JE cases was 1.27∶1.Most of them were scattered in children(44.14%)and students(27.03%).The median age of JE cases was 7 years old,mainly children under 15 years old,including 32 cases(28.83%)of 0-4 years old and 50 cases(45.05%)of 5-14 years old.The proportion of non-children’s JE cases in 2017 and 2019 exceeded that of children.The median time from onset to diagnosis of JE was 5 days.66 cases(59.46%)were clinically diagnosed and 45 cases(40.54%)were laboratory confirmed.96.40%of JE cases(107/111)had no immune history or unknown immune history.Conclusion Comprehensive measures including increasing the coverage of JE vaccine should be adopted to further reduce the incidence and mortality of JE.