2015—2016年南通地区流感病毒流行特征及变异规律研究

Epidemiological characteristics and variation of influenza virus in Nantong area from 2015 to 2016

目的了解南通地区2015—2016年度流感病毒流行特征及变异规律。方法利用荧光PCR技术对采集的流感样病例的鼻咽拭子进行检测。然后对通用引物检测阳性标本进行分型检测,经基因测序后分析本地区流感病毒核酸的变异情况。结果 2015—2016年,共收集标本1921例,阳性标本177例,阳性率为9.21%。B型、新H1N 1、甲型H3N 2流感阳性率分别为0.52%、3.12%和5.57%。流感病毒糖基化位点发现A(H1N 1)pdm流感病毒南通株、B型Yamagata系流感病毒南通株与相应的疫苗株糖基化位点相比没有突变,A(H3N2)流感病毒南通株与相应的疫苗株糖基化位点相比发生突变。H3N2亚型、新H1N1、B型Yamagata亚型及B型Victoria亚型周期性交替流行,这可能与人群流感病毒周期性变化有关,每次转换皆形成1次流行高峰,但H3N2亚型因发生变异,全年皆呈流行状态。结论本年度南通市流感病毒的流行没有明显季节性。

Objective To understand the epidemiological characteristics and variation of influenza virus in Nantong area from 2015 to 2016. Methods The nasopharyngeal swab samples of probable cases were collected and detected by fluorescence PCR. Then the genotype of the positive samples was detected by universal primers, and the variation of in- fluenza virus in the region was analyzed by gene sequencing. Results A total of 1 921 samples were collected from 2015 to 2016, and 177 postive samples were found, with a positive rate of 9.21%. The positive rates of influenza B, H1N1 and H3N2 were 0.52%, 3.12% and 5.57%, respectively. Compared to vaccine strains, the influenza virus A （H1N1） Nantong strain and Yamagata influenza virus B Nantong strain had no amino acid substitution in glycosylation sites, while the in- fluenza virus A （H3N2） Nantong strain was changed. Influenza H3N2, H1N1, B Yamagata and B Victoria had periodic epi- demics with an epidemic peak, which may be related to the periodic changes of influenza virus among the population. How- ever, due to the occurrence of H3N2 subtype variation, it was popular all year round. Conclusion The prevalence of in- fluenza virus in Nantong City has no obvious seasonal characteristics in this year.