天津市2007—2010年流感监测及H3亚型毒株HA1基因特性分析  

Surveillance of Influenza Virus and HA1 Genetic Characterizations of Group A Influenza Viruses(H3N2) Circulated in Tianjin during 2007-2010

作　　者：孔梅[1,2] 李晓燕[1,2] 邹明[1,2] 苏旭[1,2] 郭丽茹[1,2] 李琳[3] 董晓春[3] 徐文体[3] 

机构地区：[1]天津市疾病预防控制中心病原生物检测所,天津300011 [2]天津市预防医学研究所病原生物检测所 [3]天津市疾病预防控制中心传染病控制所

出　　处：《环境与健康杂志》2011年第11期992-995,共4页Journal of Environment and Health

基　　金：天津市科技支撑计划重大项目(07SYSYSF05100);天津市疾病预防控制中心2010年科技基金(2010KY1001)

摘　　要：目的了解2007—2010年天津市流感流行特点及季节性流感H3N2亚型HA1基因变异特性。方法采用MDCK细胞培养法分离流感病毒,选取14株H3亚型流感毒株进行RT-PCR扩增HA1片段,产物纯化后进行核苷酸序列测定,测定结果与WHO全球流感疫苗株序列进行同源比对,绘制种系发生树。结果采集咽拭子标本4 220份,分离出流感毒株894株,总检出率为21.2%,其中H1亚型、H3亚型、B型作为优势型交替出现。氨基酸序列分析显示H3亚型流感HA1基因随时间推移不断发生点突变,2007年初分离株有6个主要位点变异,并延续下来;2009—2010年在抗原决定簇A和B区又有4个新位点变异;种系发生树分为两支,2009—2010年的毒株产生遗传距离单成一支,而其余毒株与同期疫苗株在一分支。结论天津地区同时存在H3N2亚型、H1N1亚型、B型和新甲型H1N1流感病毒,并交替流行;H3亚型已发生抗原性漂移并有增强的趋势。Objective To investigate the prevalence character of influenza and molecular characterization of influenza A （H3N2） virus HA1 gene in Tianjin in 2007-2010. Methods Influenza viruses were isolated with MDCK cells. HA1 gene segments of 14 H3N2 subtype influenza virus strains were amplified with RT-PCR, and RT-PCR products were sequenced after purification. And then the sequences identity was compared with WHO influenza vaccine strains. Finally the phylogenetie tree was constructed according to nueleotide sequences. Results A total of 4 220 throat swabs were collected, among them, 894 influenza strains were isolated, positive rate was 21.2%. H1 subtype, H3 subtype and B type became predominant prevalence subtype alternately. Amino acid sequences analysis showed that continually point mutation was observed as time went on. Six point mutations occurred in the beginning of 2007, and these mutations continuous existed in the following three years. Five new point mutations were observed in 2009-2010 isolated strains. These point mutations located in antigenic determinant A and B areas. Phylogenic tree showed two branches. 2009-2010 isolated strains located in a separate branch, other strains stayed in the same branch with corresponding vaccine strains. Conclusion H1 subtype, H3 subtype, novel HI subtype and B type co- exist in Tianjin, and they are prevalent alternately. Antigenic drift occurs in H3 subtype influenza virus, and drift extent trends to increase. The prevalence level is related with the extent of antigenic drift.

关 键 词：流感病毒 H3N2亚型 HA1基因 变异 

分 类 号：R117[医药卫生—公共卫生与预防医学]