title: Genetic characterization of H1N2 swine influenza virus isolated in China and its pathogenesis and inflammatory responses in mice.
abstract: In 2009, two H1N2 influenza viruses were isolated from trachea swabs of pigs in Hubei in China. We compared these sequences with the other 18 complete genome sequences of swine H1N2 isolates from China during 2004 to 2010 and undertook extensive analysis of their evolutionary patterns. Six different genotypes - two reassortants between triple reassortant (TR) H3N2 and classical swine (CS) H1N1 virus, three reassortants between TR H1N2, Eurasian avian-like H1N1 swine virus and H9N2 swine virus, and one reassortant between H1N1, H3N2 human virus and CS H1N1 virus - were observed in these 20 swine H1N2 isolates. The TR H1N2 swine virus is the predominant genotype, and the two Hubei H1N2 isolates were located in this cluster. We also used a mouse model to examine the pathogenesis and inflammatory responses of the two isolates. The isolates replicated efficiently in the lung, and exhibited a strong inflammatory response, serious pathological changes and mortality in infected mice. Given the role that swine can play as putative "genetic mixing vessels" and the observed transmission of TR H1N2 in ferrets, H1N2 influenza surveillance in pigs should be increased to minimize the potential threat to public health.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Shizishan Street, Hongshan district, Wuhan, 430070, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Nan
authors.initials: N
authors.lastname: Wang
authors.forename: Jiyue
authors.initials: J
authors.lastname: Cao
authors.forename: Huanchun
authors.initials: H
authors.lastname: Chen
authors.forename: Meilin
authors.initials: M
authors.lastname: Jin
authors.forename: Hongbo
authors.initials: H
authors.lastname: Zhou
mesh_terms: D000818:Animals; D002681:China; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics; D057221:Influenza A Virus, H1N2 Subtype / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity*; D053122:Influenza A Virus, H3N2 Subtype / Q000235:genetics; D053127:Influenza A Virus, H9N2 Subtype / Q000235:genetics; D051379:Mice; D009976:Orthomyxoviridae Infections / Q000276:immunology / Q000401:mortality / Q000662:veterinary* / Q000821:virology; D016865:Reassortant Viruses / Q000235:genetics* / Q000302:isolation & purification; D013552:Swine / Q000821:virology; D013553:Swine Diseases / Q000821:virology*