郴州市2007年流感病原学监测及A/H3N2亚型血凝素基因特性研究

Molecular Characterization of Hemagglution Gene of Influenza A/H3N2 Virus and Results of Pathogenic Monitoring of Influenza in Chenzhou in 2007

目的对郴州市2007年流行性感冒的病原学监测结果进行分析,了解流感病毒优势流行毒株A(H3N2)亚型的基因变异特征。方法采用流感样病例(ILI)的咽拭子标本用狗肾细胞(MDCK)进行病毒分离培养,采用血凝(HA)及血凝抑制(HI)方法进行流感病毒初筛及分型鉴定;取病原学监测中分离到的4株A(H3N2)亚型毒株,对其血凝素基因进行逆转录-聚合酶链反应,扩增产物纯化后测序,测序结果与WHO全球流感疫苗序列进行同源比对。结果共检测4所哨点医院ILI咽拭子标本1435份,分离到流感病毒277株;阳性率19.30%,其中A(H3N2)亚型毒株156株。2007年分离株与北半球疫苗株A/Wisconsin/67/05比较,发生了变异。结论 A(H3N2)亚型流感病毒为郴州市2007年优势毒株,A(H3N2)亚型流感流行株的HA1基因发生了变异,可能是导致其流行的重要原因。

Objective To analyze the epidemic situation and the distribution of types of influenza virus, and to know the molecular characterization of influenza A （H3N2） virus in prevalence in Ohenzhou in 2007. Methods The throat swab specimens were collected from cases with influenza - like illness （ILl） in influenza monitoring hospitals. Influenza virus was isolated with MDCK cells and then identified by HA and HI methods. 4 strains of influenza A （H3N2） virus were isolated form sentinel hospitals, and hemagglutination genes of 4 strains were amplified by RT PCR. The products were purified and sequenced. Results A total of 1,435 specimens were tested, and 277 influenza virus stains were isolated. The positive rate was 19.30%. 156 stains of A （H3N2） influenza virus were isolated. As compared with the northern hemisphere vaccine strain A/Wisconsin/67/05 in 2007, the variation sites of influenza strains isolated occurred. Conclusions Influenza A （H3N2） virus was the predominant epidemic strain in Chenzhou in 2007. HA1 gene variation of influenza A （H3N2） virus in Chenzhou in 2007 was recorded, which suggested it was the main cause leading to the spread of influenza.