Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai 200241, China.
Vet Microbiol. 2011 Apr 21;149(1-2):254-61. doi: 10.1016/j.vetmic.2010.11.008. Epub 2010 Nov 9.
Pandemic strains of influenza A virus might arise by genetic reassortment between viruses from different hosts. Pigs are susceptible to both human and avian influenza viruses and have been proposed to be intermediate hosts or mixing vessels, for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. In this study, we summarize and report for the first time the coexistence of 10 (A-J) genotypes in pigs in China by analyzing the eight genes of 28 swine H9N2 viruses isolated in China from 1998 to 2007. Swine H9N2 viruses in genotype A and B were completely derived from Y280-like and Shanghai/F/98-like viruses, respectively, which indicated avian-to-pig interspecies transmission of H9N2 viruses did exist in China. The other eight genotype (C-J) viruses might be double-reassortant viruses, in which six genotype (E-J) viruses possessed 1-4 H5-like gene segments indicating they were reassortants of H9 and H5 viruses. In conclusion, genetic diversity of H9N2 influenza viruses from pigs in China provides further evidence that avian to pig interspecies transmission of H9N2 viruses did occur and might result in the generation of new reassortant viruses by genetic reassortment with swine H1N1, H1N2 and H3N2 influenza viruses, therefore, these swine H9N2 influenza viruses might be a potential threat to human health and continuing to carry out swine influenza virus surveillance in China is of great significance.
流感 A 病毒的大流行株可能是由来自不同宿主的病毒之间的基因重配产生的。猪既容易感染人流感病毒，也容易感染禽流感病毒，因此被认为是通过重配或适应哺乳动物宿主而产生大流行流感病毒的中间宿主或混合容器。在这项研究中，我们通过分析 1998 年至 2007 年期间从中国分离的 28 株猪 H9N2 病毒的 8 个基因，首次总结并报告了中国猪中存在 10 种（A-J）基因型的情况。基因型 A 和 B 的猪 H9N2 病毒分别完全来源于 Y280 样和上海/F/98 样病毒，这表明 H9N2 病毒在我国确实存在从禽到猪的种间传播。其他 8 种基因型（C-J）病毒可能是双重重配病毒，其中 6 种基因型（E-J）病毒具有 1-4 个 H5 样基因片段，表明它们是 H9 和 H5 病毒的重配体。总之，我国猪源 H9N2 流感病毒的遗传多样性进一步证明了 H9N2 病毒确实存在从禽到猪的种间传播，并且可能通过与猪源 H1N1、H1N2 和 H3N2 流感病毒的基因重配产生新的重配病毒，因此这些猪源 H9N2 流感病毒可能对人类健康构成潜在威胁，继续在中国开展流感病毒监测具有重要意义。
