摘要
目的了解2017—2018年江苏省常州地区H3N2流感病毒血凝素(hemagglutinin,HA)基因的流行特征和变异情况。方法收集2017年4月至2018年3月常州市流感监测哨点医院采集的流感样病例咽拭子标本,用实时荧光定量RT-PCR的方法检测流感病毒核酸,H3N2阳性标本进行病毒分离,获得毒株后进行HA基因扩增和测序。结果在2017年4月至2018年3月间共分离获得28株甲型H3N2流感病毒毒株,经基因测序后构建系统进化树,发现其全部属于Group3C.2a,与同期疫苗株A/Hong Kong/4801/2014类似。将常州市分离的甲型H3N2流感病毒株与A/Hong Kong/4801/2014疫苗株在HA氨基酸序列上进行差异分析,发现常州分离的流行毒株在HA抗原决定簇(A-E)区域,有10个氨基酸位点突变,在HA抗原的茎部区域有2个氨基酸位点突变。结论2017年4月至2018年3月间常州市流行的H3N2流感病毒与同期疫苗株A/Hong Kong/4801/2014(group 3C.2a)分布在同一进化分枝上,呈现1个基因亚组为主流的流行趋势,但HA抗原决定簇有部分氨基酸位点发生了突变,提示可能有变异发生,可能会对疫苗免疫效果产生一定的影响,需要在今后的工作中加强监测。
Objective To understand the epidemiological characteristics and variation of H3N2 influenza virus hemagglutinin(HA)gene in Changzhou from 2017 to 2018.Methods Throat swab specimens of the influenza-like cases were collected from Changzhou Influenza Monitoring Sentinel Hospital from April 2017 to March 2018.RNA was extracted from the specimens for influenza diagnosing and genotyping using real-time RT-PCR.H3N2 positive samples were isolated,and extracted RNA was used for amplification,sequencing and phylogenetic analysis of HA gene.Results From April 2017 to March 2018,28 strains of influenza A(H3N2)virus were isolated.After gene sequencing,a phylogenetic tree was constructed.It was found that all of the strains belonged to Group3C.2a,which was similar to the vaccine strain A/Hong Kong/4801/2014.The HA amino acid sequence difference was analyzed and compared between the H3N2 influenza virus strains isolated in Changzhou and the vaccine strain A/Hong Kong/4801/2014.It was found that the epidemic strain isolated in Changzhou was in the HA epitope(A-E)region.Ten amino acid site mutations in the HA epitope(A-E)region and two amino acid site mutations in the stem region of HA antigen were found.Conclusion From April 2017 to March 2018,the influenza virus H3N2 prevalent in Changzhou was distributed on the same evolutionary branch with the vaccine strain A/Hong Kong/4801/2014(group 3C.2a),rendering the popular trend of one subgroup.However,some amino acid sites of the HA epitope had variations,suggesting that mutations may occur,which may affect the immune effect of the vaccine.Monitoring needs to be strengthened in the future work.
作者
李琼
姚萍
蒋靖怡
毛旭建
李书书
王凤鸣
LI Qiong;YAO Ping;JIANG Jingyi;MAO Xujian;LI Shushu;WANG Fengming(Testing Center,Center for Disease Control and Prevention,Changzhou,Jiangsu 213022,China)
出处
《公共卫生与预防医学》
2020年第6期37-41,共5页
Journal of Public Health and Preventive Medicine
基金
国家自然科学基金青年项目(81803198)
江苏省自然科学基金项目(BK20180187)
常州市科技项目(CJ20190071)。
关键词
H3N2流感病毒
血凝素
基因特征
H3N2 influenza virus
Hemagglutinin
Gene characteristics
