2010年广州市甲型H1N1流感病毒分离株NA基因变异分析

Analysis on the NA gene variation of influenza A(H1N1) virus from Guangzhou in 2010

目的比较2010年从广州市分离到的甲型H1N1流感病毒神经氨酸酶(NA)基因与2009年中国大陆甲型H1N1流感病毒NA基因的变异情况,为甲型H1N1流感的监测和防控提供参考资料。方法收集2010年广州市有发热和呼吸道症状患者的咽拭子标本,用甲型H1N1流感病毒特异性引物进行聚合酶链反应(PCR)检测,扩增分离到的甲型H1N1流感病毒NA基因片段,测序后与2009年的H1N1毒株进行比对和进化分析,并用生物信息学方法对耐药位点和糖基化位点进行分析。结果共收集1 194份咽拭子标本,检测到甲型流感病毒阳性327份,其中H1N1流感病毒6株,与2009年分离的甲型H1N1流感病毒相比,有16个位点发生了有义突变,3个位点和NA活性相关,其中222位氨基酸的变异位于NA活性位点上。结论成功扩增了2010年广州市6株甲型H1N1流感病毒株NA基因并测序,未发现H275Y耐药位点的变异。3毒株在NA活性位点222位、228位和425位等氨基酸位点处发生了变异,需继续加强监测。

Objective To compare the variations of neuraminidase （NA） gene of influenza A （ H1 N1 ） virus from Guangzhou in 2010 and NA gene of influenza A （ H1N1 ） virus from Chinese mainland in 2009, and to provide the reference for the surveillance and prevention of influenza A （ H1N1 ） virus. Methods Specimens were collected from patients with febrile respiratory tract symptoms from Guangzhou in 2010. The specimens were determined with influenza A （H1N1） virus specificity primers by polymerase chain reaction （PCR）. The fragment of NA gene was amplified. After sequencing, the results were compared with influenza A （H1N1） virus in 2009. The drug resistance sites and glycosylation sites were analyzed by biometric software. Results A total of 1 194 specimens were collected, and 327 influenza A virus strains were detected, including 6 strains were identified with influenza A （ H1 N1 ） virus. Compared with influenza A （H1N1） virus in 2009, there were 16 amino acid sites with variation. There were 3 amino acid sites relating with NA activity. However, the amino acid site 222 located in the NA activity sites. Conclusions NA geue of the 6 strains of influenza A （H1N1） virus are amplified and sequenced successfully, and H275Y drug resistant site is not found. The amino acid site 222, 228 and 425 locating in NA activity sites are found with mutations in 3 strains. Therefore, the monitoring should be strengthened.