Liu Ti, Peng Yousong, Wu Julong, Lu Shangwen, He Yujie, Li Xiyan, Sun Lin, Song Shaoxia, Zhang Shengyang, Li Zhong, Wang Xianjun, Zhang Shu, Liu Mi, Kou Zengqiang
Shandong Provincial Key Laboratory of Infectious Disease Control and Prevention, Shandong Center for Disease Control and Prevention, Jinan, China.
Bioinformatics Center, College of Biology, Hunan Provincial Key Laboratory of Medical Virology, Hunan University, Changsha, China.
Front Microbiol. 2022 Nov 3;13:1030545. doi: 10.3389/fmicb.2022.1030545. eCollection 2022.
Avian influenza viruses (AIVs) seriously affect the poultry industry and pose a great threat to humans. Timely surveillance of AIVs is the basis for preparedness of the virus. This study reported the long-term surveillance of AIVs in the live bird market (LBM) of 16 cities in Shandong province from 2013 to 2019. A total of 29,895 samples were obtained and the overall positive rate of AIVs was 9.7%. The H9 was found to be the most predominant subtype in most of the time and contributed most to the monthly positve rate of AIVs as supported by the univariate and multivariate analysis, while H5 and H7 only circulated in some short periods. Then, the whole-genome sequences of 62 representative H9N2 viruses including one human isolate from a 7-year-old boy in were determined and they were genetically similar to each other with the median pairwise sequence identities ranging from 0.96 to 0.98 for all segments. The newly sequenced viruses were most similar to viruses isolated in chickens in mainland China, especially the provinces in Eastern China. Phylogenetic analysis showed that these newly sequenced H9N2 viruses belonged to the same clade for all segments except PB1. Nearly all of these viruses belonged to the G57 genotype which has dominated in China since 2010. Finally, several molecular markers associated with human adaptation, mammalian virulence, and drug resistance were identified in the newly sequenced H9N2 viruses. Overall, the study deepens our understanding of the epidemic and evolution of AIVs and provides a basis for effective control of AIVs in China.
禽流感病毒（AIVs）严重影响家禽业，并对人类构成巨大威胁。及时监测禽流感病毒是防范该病毒的基础。本研究报告了2013年至2019年山东省16个城市活禽市场（LBM）禽流感病毒的长期监测情况。共采集了29,895份样本，禽流感病毒的总体阳性率为9.7%。单因素和多因素分析表明，H9在大多数时间是最主要的亚型，对禽流感病毒的月度阳性率贡献最大，而H5和H7仅在某些短时期内传播。然后，测定了62株代表性H9N2病毒的全基因组序列，其中包括从一名7岁男孩分离出的1株人源毒株，所有片段的中位成对序列同一性在0.96至0.98之间，它们彼此在基因上相似。新测序的病毒与中国大陆尤其是华东省份鸡群中分离出的病毒最为相似。系统发育分析表明，除PB1外，这些新测序的H9N2病毒所有片段均属于同一进化枝。几乎所有这些病毒都属于自2010年以来在中国占主导地位的G57基因型。最后，在新测序的H9N病毒中鉴定出了几个与人类适应性、哺乳动物毒力和耐药性相关的分子标记。总体而言，该研究加深了我们对禽流感病毒流行和进化的理解，并为中国有效防控禽流感病毒提供了依据。
