2013-2016年浙江省杭州市萧山区人感染H7N9禽流感病例流行病学特征分析

Epidemiological characteristics of human infection with avian influenza A(H7N9)virus in Xiaoshan,China,2013-2016

目的分析浙江省杭州市萧山区2013-2016年人感染H7N9禽流感病例的流行病学特征。方法收集现住址位于萧山区的人感染H7N9禽流感确诊病例流行病学资料,通过SPSS 16.0软件,采用t检验、χ2检验、秩和检验等方法分析死亡和存活病例的流行病学特征;同时分析外环境监测结果的流行病学特征。结果 2013-2016年萧山区共确诊22例人感染H7N9禽流感病例,死亡12例(病死率54.55%)。发病集中在冬春季节,多数病例有禽类暴露史,以既往有慢性基础性疾病的老年人为主,χ2检验发现死亡组中有慢性基础性疾病的病例所占比例要高于存活组(P=0.01);外环境监测阳性率也呈现冬春高夏秋低的季节性消长。结论外环境监测阳性率与发病趋势基本吻合,由于外环境监测阳性率又有抬头趋势,须警惕新病例的发生,尤其是在农村地区以及职业暴露人群,也需要进一步提高基层的识别和诊治等防控能力。

To analyze the epidemiological characteristics of human infection with avian influenza A（H7N9） virus from 2013 to 2016 in Xiaoshan, China, we collected the epidemiological data of human A（H7Ng） cases as well as the results of environmental monitoring and analyzed it by case study, descriptive epidemiological method, and statistical analysis. Results showed that a total of 22 cases were confirmed, including 12 deaths. All the cases occurred in winter and spring, and most of them had been exposed to live poultry, and with the underlying condition of chronic diseases. Chi-square test showed that the ratio of cases with chronic diseases in death group was higher （P= 0.01）. The environmental monitoring result showed there were distinctive seasonal differences of positive rate with peaks in winter and spring and nadirs in autumn and summer. Positive rates for the samples from external environmental monitoring were consistent with the distribution of the case onset. Due to rise of environmental monitoring positive rate, we should be alert to the occurrence of new cases, especially in rural areas where live poultry fairs still exist and among people with occupational exposure. We should further improve ability to prevent and control this disease.