论文部分内容阅读
目的了解2007-2009年郴州市H3N2亚型流感病毒流行情况及血凝素基因变异特征。方法 按时间先后顺序随机选择2007-2009年流感病原学监测中分离到的H3N2亚型毒株8株,提取病毒核糖核酸(RNA),采用RT-PCR法扩增病毒HA1基因,纯化产物进行核苷酸序列测定并推导其氨基酸序列进行基因特性分析。结果H3N2亚型流感病毒在2007年为优势株,2008-2009年相对H1N1亚型流感病毒为弱势株;2007年分离株与该年疫苗株(A/Wisconsin/67/2005)比较,变异位点主要为G50E、S138A、K140I、R142G、N144D和L157S,抗原性发生了漂移;2008年分离株与2008-2009年疫苗株(A/Brisbane/10/2007)比较,变异位点主要为R142G、L157S;2009年分离株与该年疫苗株比较,变异位点主要为L157S、K173Q,2008-2009年分离株与该年疫苗株比较未发生明显变异。结论郴州市2007年H3N2亚型流感病毒HA1发生了明显变异,H3N2流感病毒较活跃,当年生产的疫苗预防效果较差;2008-2009年H3N2亚型流感病毒HA1与该年度疫苗株相比未发生明显变异,人群对其建立较好的免疫屏障,这是郴州市2008-2009年H3N2亚型流感病毒活动水平较低的主要原因。
Objective To understand the prevalence of H3N2 subtype influenza virus and genetic variation of hemagglutinin in Chenzhou from 2007 to 2009. Methods Eight strains of H3N2 subtypes isolated from 2007-2009 influenza etiology were randomly selected according to time sequence. The viral RNA was extracted and the HA1 gene was amplified by RT-PCR. The nucleotide sequence was determined and its amino acid sequence was deduced for gene characterization. Results Influenza H3N2 subtype influenza virus was the predominant strain in 2007 and the relative H1N1 subtype influenza virus was the weakest strain in 2008-2009. Compared with the vaccine strain (A / Wisconsin / 67/2005) in 2007, the variation locus The main antigens were G50E, S138A, K140I, R142G, N144D and L157S. The isolates were separated from the vaccine strains in 2008-2009 (A / Brisbane / 10/2007). The main variation sites were R142G, L157S ; 2009 isolates and vaccine strains compared to the year, the major variation sites L157S, K173Q, 2008-2009 isolates and vaccine strains that there was no significant variation. Conclusion In 2007, influenza H3N2 subtype influenza virus HA1 was significantly mutated in Chenzhou City, H3N2 influenza virus was more active, and the vaccine produced in that year was less effective. In 2008-2009, HA1 of H3N2 subtype influenza virus did not occur compared with the vaccine strain of the year Significant variation, the population to establish a better immune barrier, which is Chenzhou 2008-2009 H3N2 subtype influenza virus activity is the main reason for the lower level.