南平市2011年-2015年流行性感冒监测结果分析

Analysis of surveillance results of influenza in Nanping from 2011 to 2015

目的了解南平市2011年-2015年的流感样病例（ILI）病原学特点,为南平市流感的防控工作提供科学依据。方法根据国家流感监测方案,采集哨点医院ILI鼻咽拭子标本,使用实时荧光定量PCR方法进行流感病毒亚型鉴定,阳性标本用MDCK细胞进行病毒分离,构成比和率的比较采用χ-2检验。结果 2011年-2015年南平市流感监测哨点医院ILI就诊比例为3.03%-3.76%,共核酸检测流感样病例标本7 799份,阳性1 178份,阳性率为15.1%,分离到流感病毒毒株587株,分离率为49.8%;主要的流行毒株每年存在交替现象;每年有冬季和夏季2个流行高峰;5岁-年龄组流感病毒阳性率最高,60岁-年龄组最低,不同年龄组阳性率差异有统计学意义（χ2=124.323,P〈0.01）。结论2011年-2015年南平市的流感病毒活动强度总体平稳,流感病毒优势亚型呈现交替频繁的特征,尚未发现变异株及高致病株;流行具有明显的季节性,儿童和青少年是易感人群;因此需要长期对南平市流感进行病原学监测,为进一步控制流感的传播提供理论基础。

Objective To investigate the epidemical characteristics of the influenza- like illness（ ILI） in Nanping from 2011 to2015,so as to provide scientific basis for influenza prevention and control of Nanping. Methods Based on national influenza surveillance program,swabs were collected from influenza- like patients in sentinel hospitals. Real time PCR was used to identify virus subtypes. The strains were isolated from Madin Darby Canine Kidney cells（ MDCK cells）. Chi square test was used for the comparison of constituent ratios and rates. Results ILI percentage was within 3. 03%- 3. 76% in sentinel hospitals in Nanping during 2011- 2015. Total nucleic acid was detected in 7 799 influenza like cases,1 178 cases were positive,and the positive rate was 15. 1%. A total of 587 strains of influenza viruses were isolated,with an isolation rate of 49. 8%. The predominant strains showed alternation annually. And there were two peaks distributed in winter and summer every year. The positive rate of influenza virus was the highest in the age group of 5 - years old,and the lowest in the age group of 60 - years old. The positive rate of influenza virus was different among different age groups（ χ2= 124. 323,P 〈0. 01）. Conclusion Influenza virus activity intensity is generally stable in Nanping from 2011 to 2015,there were frequent alternations among different virus subtypes. The variant and highly pathogenic strains had not been detected. The incidence of influenza has obvious seasonality.Children and adolescents are the susceptible population,so it needs to etiological supervision on influenza in Nanping for a long- term,so as to provide theoretical basis for further controlling the spread of flu.