Wan Zhimin, Kan Qiuqi, Zhao Zhehong, Shao Hongxia, Deliberto Thomas J, Wan Xiu-Feng, Qin Aijian, Ye Jianqiang
Key Laboratory of Jiangsu Preventive Veterinary Medicine, Key Laboratory for Avian Preventive Medicine, Ministry of Education, College of Veterinary Medicine, Yangzhou University, Yangzhou, China.
Institute of Agricultural Science and Technology Development, Yangzhou University, Yangzhou, China.
Front Vet Sci. 2021 Sep 13;8:685399. doi: 10.3389/fvets.2021.685399. eCollection 2021.
Subtype H6 avian influenza A viruses (IAVs) are enzootic and genetically diverse in both domestic poultry and wild waterfowl and may cause spillovers in both pigs and humans. Thus, it is important to understand the genetic diversity of H6 IAVs in birds and their zoonotic potential. Compared with that in domestic poultry, the genetic diversity of H6 viruses in wild birds in China has not been well-understood. In this study, five H6 viruses were isolated from wild birds in Poyang Lake, China, and genetic analyses showed that these isolates are clustered into four genotypes associated with reassortments among avian IAVs from domestic poultry and wild birds in China and those from Eurasia and North America and that these viruses exhibited distinct phenotypes in growth kinetics analyses with avian and mammalian cells lines and in mouse challenge experiments. Of interest is that two H6 isolates from the Eurasian teal replicated effectively in the mouse lung without prior adaptation, whereas the other three did not. Our study suggested that there are variations in the mammalian viral replication efficiency phenotypic among genetically diverse H6 IAVs in wild birds and that both intra- and inter-continental movements of IAVs through wild bird migration may facilitate the emergence of novel H6 IAV reassortants with the potential for replicating in mammals, including humans. Continued surveillance to monitor the diversity of H6 IAVs in wild birds is necessary to increase our understanding of the natural history of IAVs.
H6亚型甲型禽流感病毒（IAV）在家禽和野生水禽中呈地方流行性且基因多样，并且可能在猪和人类中发生病毒外溢。因此，了解鸟类中H6 IAV的基因多样性及其人畜共患病潜力很重要。与家禽相比，中国野生鸟类中H6病毒的基因多样性尚未得到很好的了解。在本研究中，从中国鄱阳湖的野生鸟类中分离出5株H6病毒，基因分析表明，这些分离株聚类为四种基因型，与来自中国家禽和野生鸟类以及欧亚大陆和北美的禽流感病毒之间的重配有关，并且这些病毒在禽和哺乳动物细胞系的生长动力学分析以及小鼠攻毒实验中表现出不同的表型。有趣的是，来自欧亚绿头鸭的两株H6分离株在未经预先适应的情况下能在小鼠肺中有效复制，而其他三株则不能。我们的研究表明，野生鸟类中基因多样的H6 IAV在哺乳动物病毒复制效率表型上存在差异，并且IAV通过野生鸟类迁徙在洲际和洲内的传播可能促进具有在包括人类在内的哺乳动物中复制潜力的新型H6 IAV重配体的出现。持续监测野生鸟类中H6 IAV的多样性对于增进我们对IAV自然史的了解是必要的。
