College of Life Science and Engineering, Foshan University, Foshan, 528231, Guangdong, China.
College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, China.
BMC Vet Res. 2021 May 28;17(1):200. doi: 10.1186/s12917-021-02903-z.
Highly pathogenic avian influenza viruses (HPAIVs) of H5 subtype pose a great threat to the poultry industry and human health. In recent years, H5N6 subtype has rapidly replaced H5N1 as the most predominate HPAIV subtype circulating in domestic poultry in China. In this study, we describe the genetic and phylogenetic characteristics of a prevalent H5N6 strain in Guangdong, China.
Nucleotide sequencing identified a H5N6 subtype HPAIV, designated as A/chicken/Dongguan/1101/2019 (DG/19), with a multibasic cleavage site in the hemagglutinin (HA). Phylogenetic analysis revealed DG/19 was a reassortant of H5N1, H5N2, H5N8, and H6N6 subtypes of avian influenza viruses. A number of mammalian adaptive markers such as D36N in the HA were identified.
Our results showed that HPAIV H5N6 strains still emerge in well-managed groups of chicken farms. Considering the increasing prevalence of H5N6 HPAIV, and the fact that H5N6 HPAIVs are well adapted to migratory birds, an enhanced surveillance for the East Asian-Australasian flyway should be undertaken to prevent potential threats to the poultry industry and human health.
高致病性禽流感病毒（HPAIV）H5 亚型对家禽业和人类健康构成巨大威胁。近年来，H5N6 亚型迅速取代 H5N1 成为中国家禽中流行的主要 HPAIV 亚型。本研究描述了中国广东流行的 H5N6 株的遗传和系统进化特征。
核苷酸序列鉴定出一种 H5N6 亚型高致病性禽流感病毒，命名为 A/鸡/东莞/1101/2019（DG/19），其血凝素（HA）具有多碱性裂解位点。系统进化分析显示，DG/19 是 H5N1、H5N2、H5N8 和 H6N6 亚型禽流感病毒的重组病毒。鉴定出 HA 中的多个哺乳动物适应性标记，如 D36N。
我们的研究结果表明，高致病性禽流感病毒 H5N6 株仍在管理良好的鸡群中出现。鉴于 H5N6 HPAIV 的流行率不断增加，以及 H5N6 HPAIV 已很好地适应候鸟的事实，应加强对东亚-澳大拉西亚飞行路线的监测，以防止对家禽业和人类健康造成潜在威胁。
