不同年龄人群在流感流行中作用分析

Role of populations of different age in epidemic of influenza

目的分析不同年龄组人群在流感流行过程中的作用。方法采用7d移动平均数法寻找流感样病例流行波,分析流行波与流感病毒检出率的关系,利用不同年龄组流行波中位数分析不同年龄组人群在流感样病例流行中的特征。结果周流感样病例数与流感病毒阳性检出率相关系数为0.46（95%CI=0.29~0.60）,4次流行波中有3次流感与流感疫情高度相关;低年龄组人群在季节性流感疫情中率先发病。结论流感样病例疫情与流感阳性检出率联系密切;在季节性流感流行过程中小年龄组人群是流感疫情控制的重点人群,新型流感出现时当以率先流行的人群为重点人群。

Objective To analyze the role of populations of different age in the influenza epidemics in Jiaxing city between 2009 and 2011.Methods Seven-day moving averages method was used to find the epidemic wave of influenza-like illness;the relationship between the epidemic wave and influenza virus detection rate was analyzed and the median and interquartile range of epidemic curve was calculated to estimate the role of different age groups in the influenza epidemic session.Results The correlation coefficient between weekly influenza-like cases and influenza virus positive rate was 0.46（95% confidence interval[95%CI]：0.29-0.60）and the three in four epidemic waves showed around50%influenza positive rate.The young age group and the populations at the age of5-24 years were the leading groups during seasonal and pH1N1 epidemic, respectively. Conclusion Influenza-like illness epidemic is closely related with influenza-positive detection rate;during the seasonal influenza epidemics,small age group is the key population,while for new influenza epidemic the leading transmission population is the control target.