title: Isolation and genetic characterization of avian-like H1N1 and novel ressortant H1N2 influenza viruses from pigs in China.
abstract: As pigs are susceptible to both human and avian influenza viruses, they 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 reported avian-like H1N1 and novel ressortant H1N2 influenza viruses from pigs in China. Homology and phylogenetic analyses showed that the H1N1 virus (A/swine/Zhejiang/1/07) was closely to avian-like H1N1 viruses and seemed to be derived from the European swine H1N1 viruses, which was for the first time reported in China; and the two H1N2 viruses (A/swine/Shanghai/1/07 and A/swine/Guangxi/13/06) were novel ressortant H1N2 influenza viruses containing genes from the classical swine (HA, NP, M and NS), human (NA and PB1) and avian (PB2 and PA) lineages, which indicted that the reassortment among human, avian, and swine influenza viruses had taken place in pigs in China and resulted in the generation of new viruses. The isolation of avian-like H1N1 influenza virus originated from the European swine H1N1 viruses, especially the emergence of two novel ressortant H1N2 influenza viruses provides further evidence that pigs serve as intermediate hosts or "mixing vessels", and swine influenza virus surveillance in China should be given a high priority.
authors.affiliation: Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai 200241, China.
authors.forename: Hai
authors.initials: H
authors.lastname: Yu
authors.forename: Peng-Chao
authors.initials: PC
authors.lastname: Zhang
authors.forename: Yan-Jun
authors.initials: YJ
authors.lastname: Zhou
authors.forename: Guo-Xin
authors.initials: GX
authors.lastname: Li
authors.forename: Jie
authors.initials: J
authors.lastname: Pan
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Yan
authors.forename: Xiao-Xiao
authors.initials: XX
authors.lastname: Shi
authors.forename: Hui-Li
authors.initials: HL
authors.lastname: Liu
authors.forename: Guang-Zhi
authors.initials: GZ
authors.lastname: Tong
mesh_terms: D000818:Animals; D001717:Birds; D002681:China; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D005585:Influenza in Birds / Q000821:virology; D009976:Orthomyxoviridae Infections / Q000821:virology*; D010802:Phylogeny; D016865:Reassortant Viruses / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D013552:Swine / Q000821:virology*