南京市2006-2015年流感流行病学特征分析

目的 分析2006-2015年南京市流行性感冒（简称流感）流行病学特征，为流感防控提供依据。方法 在中国疾病预防控制中心信息系统下载流感样病例（influenza like illness，ILI）监测、流感暴发疫情监测和病原学监测资料，应用SPSS 16.0软件进行数据分析。结果 2006-2015年ILI数和流感样病例百分比（ILI%）平均分别为5823例和5.0%，ILI 5岁以下组所占比例最高（64.8%），60岁及以上年龄组所占比例最低（2.1%）；2006-2015年南京市共分离检测流ILI标本31644例，阳性病例4762例，阳性率15.0%，不同年份、不同年龄段之间核酸检测阳性率差异均有统计学意义（均有P<0.05）；阳性标本中季节性H3N21944例（40.8%），其次是B型流感1374例（28.9%），甲型H1N1次之1243例（26.1%），季节性H1N1最少201例（4.2%）；不同年龄段人群流感分型构成差异有统计学意义（χ2=317.19，P<0.001）。结论 ILI主要分布在5岁以下儿童，2006-2015年流感各亚型交替成为优势毒株，不同年龄段感染主要亚型不同。

Epidemiological characteristics analysis of influenza in Nanjing City from 2006 to 2015

Objective To investigate the epidemiologic characteristics of influenza in Nanjing from 2006 to 2015 in order to provide scientific evidence for developing strategies on the influenza prevention and control.Methods Data was collected from China information system for diseases control and prevention,including influenza-like illness(ILI) case report,pathogen surveillance,and influenza outbreak report.Data analysis was conducted by SPSS 16.0.Results From 2006 to 2015,in average,5 823 ILI cases were reported annually,and the average annual ILI％ was 5.0％.Among different age groups,children under the age of 5 accounted for the highest percentage(64.8％),whereas people aged 60 years and older had the lowest percentage (2.1％).From 2006 to 2015,a total of 31 644 throat swab specimens were collected and tested for ILI,in which 4 762 cases were tested positive (15.0％).The positive rate varied among different years,and different age groups (all P＜0.05).Among the4 762 cases,1 944 H3N2 types,1 374 B types,1 243 H1N1(09pdm) types,and 201 seasonal H1N1 types were identified with the percentage of 40.8 ％,28.9％,26.1％,and 4.2％,respectively.The percentages of virus subtypes were significantly different among different age groups (x2 =317.19,P ＜ 0.001).Conclusions The percentage of ILI in children under the age of 5 was the highest.Different influenza subtypes altered to become the dominant strain.The main subtypes of influenza were different among different age groups.