Jin Hongmei, Wang Deli, Sun Jing, Cui Yanfang, Chen Guang, Zhang Xiaolin, Zhang Jiajie, Li Xiang, Chai Hongliang, Gao Yuwei, Li Yanbing, Hua Yuping
College of Wildlife Resources, Northeast Forestry University Harbin, China.
Harbin Veterinary Research Institute, Chinese Academy of Agriculture Sciences Harbin, China.
Front Microbiol. 2016 Jul 7;7:1066. doi: 10.3389/fmicb.2016.01066. eCollection 2016.
The emergence of human infections with a novel H7N9 influenza strain has raised global concerns about a potential human pandemic. To further understand the character of other influenza viruses of the H7 subtype, we selected two H7N1 avian influenza viruses (AIVs) isolated from wild birds during routine surveillance in China: A/Baer's Pochard/Hunan/414/2010 (BP/HuN/414/10) (H7N1) and A/Common Pochard/Xianghai/420/2010 (CP/XH/420/10) (H7N1). To better understand the molecular characteristics of these two isolated H7N1 viruses, we sequenced and phylogenetically analyzed their entire genomes. The results showed that the two H7N1 strains belonged to a Eurasian branch, originating from a common ancestor. Phylogenetic analysis of their hemagglutinin (HA) genes showed that BP/HuN/414/10 and CP/XH/420/10 have a more distant genetic relationship with A/Shanghai/13/2013 (H7N9), with similarities of 91.6 and 91.4%, respectively. To assess the replication and pathogenicity of these viruses in different hosts, they were inoculated in chickens, ducks and mice. Although, both CP/XH/420/10 and BP/HuN/414/10 can infect chickens, ducks and mice, they exhibited different replication capacities in these animals. The results of this study demonstrated that two low pathogenic avian influenza (LPAI) H7N1 viruses of the Eurasian branch could infect mammals and may even have the potential to infect humans. Therefore, it is important to monitor H7 viruses in both domestic and wild birds.
一种新型H7N9流感病毒导致人类感染事件的出现引发了全球对可能发生人类大流行的担忧。为了进一步了解H7亚型其他流感病毒的特性，我们选取了在中国常规监测期间从野生鸟类中分离出的两种H7N1禽流感病毒（AIV）：A/中华秋沙鸭/湖南/414/2010（BP/HuN/414/10）（H7N1）和A/普通秋沙鸭/向海/420/2010（CP/XH/420/10）（H7N1）。为了更好地了解这两种分离出的H7N1病毒的分子特征，我们对它们的全基因组进行了测序和系统发育分析。结果表明，这两种H7N1毒株属于欧亚分支，源自一个共同祖先。对其血凝素（HA）基因的系统发育分析表明，BP/HuN/414/10和CP/XH/420/10与A/上海/13/2013（H7N9）的遗传关系更远，相似度分别为91.6%和91.4%。为了评估这些病毒在不同宿主中的复制和致病性，将它们接种到鸡、鸭和小鼠体内。虽然CP/XH/420/10和BP/HuN/414/10都能感染鸡、鸭和小鼠，但它们在这些动物中的复制能力有所不同。本研究结果表明，两种欧亚分支的低致病性禽流感（LPAI）H7N1病毒可感染哺乳动物，甚至可能有感染人类的潜力。因此，监测家禽和野生鸟类中的H7病毒非常重要。
