2009—2010年珠海口岸入境人员中发热病例流感病毒分子流行病学研究

目的研究2009甲型H1N1流感疫情全球大流行期间珠海口岸入境发热旅客流感病毒的分子流行病学特征。方法选择2009年5月至2010年4月经珠海各口岸入境的976例发热旅客(体温≥37.5℃)为研究对象,采集咽拭子样本并提取病毒核酸,采用3个多重RT-PCR实验进行甲型、乙型和2009新甲型H1N1流感病毒的筛查以及甲型流感病毒的分子分型检测。此外,随机选择8株2009甲型H1N1流感病毒进行HA和NA基因全长RT-PCR扩增和序列分析。采用SPSS17.0软件对流行病学和实验数据进行统计学分析。结果976例发热旅客中检出流感病毒阳性病例331例,其中甲型流感占96.98%(321/331),乙型流感占3.02%(10/331);321例甲型流感病毒分子分型结果为新甲型H1N1流感92例,占28.66%,人季节性H1N1流感65例,占20.25%,人季节性H3N2流感164例,占51.09%。序列分析显示珠海口岸输入性新甲型H1N1流感病毒的HA和NA基因与甲型流感典型毒株A/California/04/2009(H1N1)的同源性分别达到99.86%和99.89%。结论本研究所阐明的珠海口岸流感病毒的分子流行病学特征对于指导国境口岸流感的防控具有重要参考价值。

Molecular epidemiology study of influenza viruses of entry passengers with fever at Zhuhai port

Objective To study the molecular epidemiology characteristics of influenza viruses of entry passengers with fever at Zhuhai port during the 2009 influenza A(H1N1) pandemic globally.Methods A total of 976 entry passengers with fever(temperature≥37.5°C) were selected as the research objects from all the ports of Zhuhai during May 2009 to April 2010.Their throat swab specimens were collected and the virus nucleic acid was extracted.Three multiplex RT-PCR assays were used to screen type A,B and novel A(H1N1) 2009 influenza viruses simultaneously and detect the subtypes of influenza A viruses.In addition,the full length of hemagglutinin(HA) and neuraminidase(NA) genes of randomly selected 8 strains of A(H1N1) 2009 influenza viruses were amplified by RT-PCR for sequence analysis.Finally,SPSS17.0 software was used for statistical analysis of both epidemiological and experimental data.Results Of 976 febrile passengers detected,331 cases were positive for influenza viruses,of which 96.98%(321/331) were influenza A and 3.02%(10/331) were influenza B.Of 321 influenza A viruses that were subtyped,92(28.66%) were novel influenza A(H1N1) 2009,65(20.25%) were human seasonal influenza A(H1N1) and 164(51.09%) were human seasonal influenza A(H3N2).These results showed that the most common subtypes of influenza viruses do still circulate in normal ways during the 2009 influenza A(H1N1) pandemic.Sequence analysis showed that the homologies of hemagglutinin(HA) and neuraminidase(NA) genes between the influenza A(H1N1) 2009 strains isolated at Zhuhai port and the prototypical strain of A/California/04/2009(H1N1) were 99.86% and 99.89%,respectively.It was clearly visible that the genetic relationship between them was very close.Logically,the biological characteristics of them can be speculated to be similar.Conclusion The molecular epidemiologic characteristics of influenza viruses at Zhuhai port