河源市2014—2016年流感流行与监测结果分析

Influenza epidemic and monitoring in Heyuan,2014-2016

目的对河源市2014—2016年流感监测结果进行分析,了解其流行病学特征和病原学特点,为制定流感防控策略提供科学的参考依据。方法采集哨点医院的流感样病例(ILI)咽拭子标本,用荧光定量RT-PCR方法检测流感病毒核酸,用狗肾传代细胞(MDCK细胞)法对核酸阳性标本进行病毒分离并鉴定毒株型别。结果 2014年流感的检出高峰在1—4月和6—7月,2015年的检出高峰在4—8月,2016年的检出高峰在2—5月和11—12月;5个年龄组中,0~4岁组和>60岁组阳性率最高,分别为12.07%和11.96%,其后依次是5~14岁组(8.79%)、25~59岁组(7.62%),15~24岁组阳性率最低,为5.53%,0~4岁组与5~14岁组间阳性率差异有统计学意义(χ~2=13.776 3,P<0.05)。2014—2016年共检测ILI标本3 170份,流感病毒核酸阳性303份,总阳性率为9.56%。2014—2016年阳性率依次为7.79%、10.14%、10.73%。2014年和2015年,除BV外,其他三种流感病毒H1N1、H3N2、BY均有检出,2016年四种都有检出。三年里,H3N2的阳性率比其他三种流感病毒高。303份核酸阳性标本中,分离出流感病毒毒株88株(29.04%),其中H1N1 7株(2.31%)、H3N2 42株(13.86%)、BY 39株(12.87%),BV没有分离到毒株。结论河源市2014年流感较平稳,2015年和2016年活跃度逐渐增强;应加强0~4岁组和>60岁组的流感防控工作;加大H3N2亚型流感病毒的监测工作,及时掌握优势毒株的变化规律,不断完善流感监测网络体系。

Objective To analyze the results of surveillance of influenza in Heyuan City from 2014 to 2016 and find out the etiology and epidemiology characteristics of influenza, so as to provide the evidence for formulating the strategy of influenza control and prevention. Methods The throat swab specimens of influenza-like illness people were collected from the sentinel hospital for virus nucleic acid detection by fluorescence quantitative RT-PCR, and MDCK cells were used to isolate the influenza virus, and the subtype of isolated virus was identified by HA test. Results The detection peaks of influenza were from January to April and June to July in 2014, from April to August in 2015, and from February to May and November to December in 2016. The positive rate of 0-4-year age group was the highest（12.07%）, next was the 60-year age group（11.96%）, subsequently, 5-14-year age group（8.79%）, 25-59-year age group（7.62%）, and the positive rate of 15-24-year age group was the lowest（5.53%）. In the positive rates, the difference between the 0-4-year age group and 5-14 year age group was statistically significant（χ^2=13.776 3, P〈0.05）. In the total of 3 170 specimens, there were 303 samples with influenza virus positive（9.56%）. The positive rates were 7.79%, 10.14% and 10.73% in 2014, 2015 and 2016, respectively. In 2014 and 2015, three other influenza viruses were detected except BV and four were detected in 2016. In three years, H3N2 had a higher positive rate than the other three influenza viruses. Totally 88 strains of influenza virus were isolated（29.04%） in 303 positive specimens of nucleic acid, including H1N1 7 strains（2.31%）, H3N2 42 strains（13.86%）, and BY 39 strains（12.87%）, but BV was not isolated. Conclusion The activity of influenza in Heyuan City in 2014 is stable, and then gradually increases in the next two years. The control and prevention of influenza should be strengthened in the 0-4-year age group and 60-year age group. The monitoring of the H3N2 subtype influenza virus should be strengthened, the change rule of the dominant strain should be grasped in time, and the influenza surveillance network system also should be improved continuously.