2012—2017年扬州市流感病原学监测结果分析

Etiological analysis of influenza surveillance data in Yangzhou from 2012 to 2017

目的分析扬州市2012-2017年的流感监测结果，阐明近年来流感流行特征和变化趋势，为预测和防控流感流行提供科学依据。方法对江苏省苏北人民医院、扬州市第一人民医院和高邮市人民医院就诊患者进行监测采样，对流感样病例（Influenza—like illness，ILI）标本，采用实时荧光定量RT—PCR方法进行病毒核酸检测，并对结果信息进行统计分析。结果2012-2017年扬州市共采集ILI咽拭子标本18083份，其中流感核酸阳性标本1983份，阳性率为10．97％，相邻年份阳性率差异有统计学意义（x^2=167．93，P〈0．001）。全年均有流感活动，主要流行季节为冬春季和夏季，共占阳性总数的83．61％，甲型流感全年流行，而乙型流感主要在冬春季流行，各个亚型呈现交替流行。各个年龄组均有阳性病例检出，阳性率最高的是10～19岁年龄组，阳性率为16．33％，最低的是20～29岁年龄组，阳性率为8．52％。结论扬州地区2012—2017年流感流行具有明显的季节性，不同亚型毒株交替流行，高发人群以婴幼儿及青少年为主。

Objective To find out the characteristics and regularity trend of influenza activity according to the analyses of influenza surveillance data in Yangzhou from 2012 to 2017, and to provide scientific supports for predicting and controlling the pandemic outbreak of influenza effectively. Methods The influenza samples were collected from Northern Jiangsu People＇s Hospital, Yangzhou First People＇ s Hospital and Gaoyou People＇ s Hospital, using fluorescent RT-PCR method to detect influenza virus nucleic acid and classifying influenza virus subtypes. Finally, the surveillance data from January, 2012 to December, 2017 of influenza like illness （ILl） cases of Yangzhou were analyzed. Results Totally 18 083 throat swabs of ILI specimens were collected from 2012-2017 in Yangzhou, 1 983 samples were positive （ 10. 97% ） , the difference in positive rates of adjacent years was statistically significant （ x^2 = 167.93, P 〈 0. 001 ）. In Yangzhou city, influenza virus kept activative in whole year. The influenza epidemic season was winter-spring and summer, accounting for 83.61% of all positive cases, with type A influenza prevalent throughout all year and type B influenza mainly prevalent in spring and winter, each subtype showed alternating prevalence. The influenza virus infection occurred in every age group. The highest positive rate was 16.33% in the age group of 10-19 years and the lowest was 8.52% in the age group of 20-29 years among all detected age groups. Conclusions From 2012 to 2017, the epidemic of influenza in Yangzhou was obviously seasonal and all the subtypes of influenza were in prevalent status alternately. The high-risk groups of Influenza were infants and teenagers who under the age of 19 years. So a long-term influenza surveillance is much needed for the early warning and forecasting the spread of influenza.