Genetic and Molecular Characterization of H9N2 Avian Influenza Viruses Isolated from Live Poultry Markets in Hubei Province, Central China, 2013–2017

Zhibin Hu; Fuhu Peng; Zhenghui Xiong; Wanpo Zhang; Tingting Li; Yuejun Shi; Jun Xie; Xin Jin; Jingjing Huang; Hongde Xiao; Dingren Bi; Nianhua Song; Zili Li

doi:10.1007/s12250-020-00260-z

April 2021

Zhibin Hu, Fuhu Peng, Zhenghui Xiong, Wanpo Zhang, Tingting Li, Yuejun Shi, Jun Xie, Xin Jin, Jingjing Huang, Hongde Xiao, Dingren Bi, Nianhua Song and Zili Li. Genetic and Molecular Characterization of H9N2 Avian Influenza Viruses Isolated from Live Poultry Markets in Hubei Province, Central China, 2013–2017[J]. Virologica Sinica, 2021, 36(2): 291-299. doi: 10.1007/s12250-020-00260-z

Citation: Zhibin Hu, Fuhu Peng, Zhenghui Xiong, Wanpo Zhang, Tingting Li, Yuejun Shi, Jun Xie, Xin Jin, Jingjing Huang, Hongde Xiao, Dingren Bi, Nianhua Song, Zili Li. Genetic and Molecular Characterization of H9N2 Avian Influenza Viruses Isolated from Live Poultry Markets in Hubei Province, Central China, 2013–2017 .VIROLOGICA SINICA, 2021, 36(2) : 291-299. http://dx.doi.org/10.1007/s12250-020-00260-z

2013-2017年中国中部活禽市场H9N2亚型禽流感病毒分子变异分析

胡智斌 ^1,2 ,
彭伏虎 ² ,
熊正慧 ² ,
张万坡 ¹ ,
李婷婷 ² ,
史月军 ¹ ,
谢军 ² ,
金鑫 ² ,
黄晶晶 ² ,
肖宏德 ² ,
毕丁仁 ¹ ,
宋念华 ^2,, ,
李自力 ^1,,

cstr: 32224.14.s12250-020-00260-z

1.
华中农业大学动物医学院
2.
湖北省动物疫病预防控制中心

通讯作者： 宋念华, snh082@163.com, ORCID: 0000-0002-2399-5288
; 李自力, lizili@mail.hzau.edu.cn, ORCID: 0000-0002-9729-1339
收稿日期： 2020-01-17
录用日期： 2020-04-24
出版日期： 2020-09-14

摘要

H9N2亚型禽流感病毒是一种A型流感病毒，在亚洲广泛传播，危害着家禽业，并为新兴的人流感病原体提供了遗传物质。为了更好地了解H9亚型AIV的流行和遗传，我们于2013年至2017年在湖北省的活禽交易市场进行了主动监测。实时RT-PCR显示，A型流感的阳性率为26.6％（1275/4798），其中H9亚型占阳性样本的50.3％（641/1275）并在17个样本中检测到H7亚型。从分离的132株H9N2病毒株中选取48株代表性毒株进行了进化分析和基因分型。系统发育分析表明，所有H9N2病毒基因具有91.1％–100％核苷酸同源性，均属于基因型G 57，与2013年至2017年在中国人类H9N2病毒具有高度同源性。使用95％的核苷酸差异临界值，我们确定了十种不同的基因型，这些基因型随着时间而不断变化。分子分析表明，六株H9N2病毒在血凝素蛋白的218位具有额外潜在的糖基化位点，所有分离株均具有155T和226L突变(H3计数)。此外，44株毒的聚合酶2基因具有588V突变，与H9N2人感染菌株A/Beijing/1/2016和A/Beijing/1/2017相似。这些结果强调，湖北的H9N2流感病毒持续变异并经历哺乳动物适应性变化，有必要加强对活禽交易市场中H9N2禽流感病毒的监测。
- 禽流感
- , H9N2
- , 遗传变异
- , 系统发育分析
- , 活禽交易市场

Genetic and Molecular Characterization of H9N2 Avian Influenza Viruses Isolated from Live Poultry Markets in Hubei Province, Central China, 2013–2017

Zhibin Hu ^1,2 ,
Fuhu Peng ² ,
Zhenghui Xiong ² ,
Wanpo Zhang ¹ ,
Tingting Li ² ,
Yuejun Shi ¹ ,
Jun Xie ² ,
Xin Jin ² ,
Jingjing Huang ² ,
Hongde Xiao ² ,
Dingren Bi ¹ ,
Nianhua Song ^2,, ,
Zili Li ^1,,

1.
College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
2.
Hubei Center for Animal Disease Control and Prevention, Wuhan 430070, China

Corresponding author: Nianhua Song, snh082@163.com Zili Li, lizili@mail.hzau.edu.cn
ORCID: 0000-0002-2399-5288; 0000-0002-9729-1339
Received Date: 17 January 2020
Accepted Date: 24 April 2020
Published Date: 14 September 2020

Abstract

H9N2 subtype avian influenza virus (AIV) is an influenza A virus that is widely spread throughout Asia, where it jeopardizes the poultry industry and provides genetic material for emerging human pathogens. To better understand the epidemicity and genetics of H9 subtype AIVs, we conducted active surveillance in live poultry markets (LPMs) in Hubei Province from 2013 to 2017. A total of 4798 samples were collected from apparent healthy poultry and environment. Real-time RT-PCR revealed that the positivity rate of influenza A was 26.6% (1275/4798), of which the H9 subtype accounted for 50.3% (641/1275) of the positive samples. Of the 132 H9N2 viral strains isolated, 48 representative strains were subjected to evolutionary analysis and genotyping. Phylogenetic analysis revealed that all H9N2 viral genes had 91.1%–100% nucleotide homology, clustered with genotype 57, and had high homology with human H9N2 viruses isolated from 2013 to 2017 in China. Using a nucleotide divergence cutoff of 95%, we identified ten distinct H9N2 genotypes that continued to change over time. Molecular analysis demonstrated that six H9N2 isolates had additional potential glycosylation sites at position 218 in the hemagglutinin protein, and all isolates had I155T and Q226L mutations. Moreover, 44 strains had A558V mutations in the PB2 protein and four had E627V mutations, along with H9N2 human infection strains A/Beijing/1/2016 and A/Beijing/1/2017. These results emphasize that the H9N2 influenza virus in Hubei continues to mutate and undergo mammalian adaptation changes, indicating the necessity of strengthening the surveillance of the AIV H9N2 subtype in LPMs.
- Avian influenza
- , H9N2
- , Genetic variation
- , Phylogenetic analysis
- , Live poultry markets (LPMs)

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