Lai Cheng Cai, Wang Ke Yu, Chen Rui, Zhang Ai Jun, Gu Hong Jing, Yin Yan Bo, Wang Dong Dong, Liu Lin Lin, Xing Li, Tong Yi Gang, Ma Zong Juan, Yang Peng Hui, Wang Xi Liang
State Key Laboratory of Pathogens and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China.
Ningxia Medical University, Yinchuan 750004, Ningxia, China.
Biomed Environ Sci. 2017 Jan;30(1):68-74. doi: 10.3967/bes2017.009.
The highly pathogenic avian influenza (HPAI) H5N1 virus has caused several outbreaks in domestic poultry. Despite great efforts to control the spread of this virus, it continues to evolve and poses a substantial threat to public health because of a high mortality rate. In this study, we sequenced whole genomes of eight H5N1 avian influenza viruses isolated from domestic poultry in eastern China and compared them with those of typical influenza virus strains. Phylogenetic analyses showed that all eight genomes belonged to clade 2.3.2.1 and clade 7.2, the two main circulating clades in China. Viruses that clustered in clade 2.3.2.1 shared a high degree of homology with H5N1 isolates located in eastern Asian. Isolates that clustered in clade 7.2 were found to circulate throughout China, with an east-to-west density gradient. Pathogenicity studies in mice showed that these isolates replicate in the lungs, and clade 2.3.2.1 viruses exhibit a notably higher degree of virulence compared to clade 7.2 viruses. Our results contribute to the elucidation of the biological characterization and pathogenicity of HPAI H5N1 viruses.
高致病性禽流感（HPAI）H5N1病毒已在家禽中引发了多次疫情。尽管为控制该病毒的传播付出了巨大努力，但它仍在不断演变，因其高死亡率对公共卫生构成了重大威胁。在本研究中，我们对从中国东部家禽中分离出的8株H5N1禽流感病毒的全基因组进行了测序，并将它们与典型流感病毒株的基因组进行了比较。系统发育分析表明，所有8个基因组均属于2.3.2.1分支和7.2分支，这是在中国主要流行的两个分支。聚集在2.3.2.1分支中的病毒与位于东亚的H5N1分离株具有高度同源性。发现聚集在7.2分支中的分离株在中国各地传播，呈东向西的密度梯度。对小鼠的致病性研究表明，这些分离株在肺部复制，与7.2分支病毒相比，2.3.2.1分支病毒表现出明显更高的毒力。我们的研究结果有助于阐明高致病性H5N1禽流感病毒的生物学特性和致病性。
