title: Genetic characterization of swine influenza viruses isolated in Japan between 2009 and 2012.
abstract: Eleven swine influenza viruses (SIVs) isolated from pigs in Japanese institutions between 2009 and 2012 were genetically characterized. Seven H1N1 were shown to have originated from A(H1N1)pdm09 viruses. Two H1N2 viruses contained H1 and N2 genes of Japanese H1N2 SIV origin together with internal genes of A(H1N1)pdm09 viruses. Two H3N2 viruses isolated during animal quarantine were identified as triple reassortant H3N2 viruses maintained among pigs in North America. This study shows that A(H1N1)pdm09 viruses and their reassortant strains are already present in domestic pigs in Japan and that novel SIVs are possibly being imported from abroad.
authors.affiliation: Research Teams for Zoonotic Diseases, National Institute of Animal Health, National Agriculture and Food Research Organization, 3-1-5 Kannondai, Tsukuba, Ibaraki 305-0856, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Matsuu
authors.forename: Yuko
authors.initials: Y
authors.lastname: Uchida
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Takemae
authors.forename: Takahiro
authors.initials: T
authors.lastname: Mawatari
authors.forename: Shuji Kasai
authors.initials: SK
authors.lastname: Yoneyama
authors.forename: Tomoe
authors.initials: T
authors.lastname: Kasai
authors.forename: Ryoko
authors.initials: R
authors.lastname: Nakamura
authors.forename: Mariko
authors.initials: M
authors.lastname: Eto
authors.forename: Takehiko
authors.initials: T
authors.lastname: Saito
mesh_terms: D000818:Animals; D053118:Influenza A Virus, H1N1 Subtype / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D057221:Influenza A Virus, H1N2 Subtype / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D053122:Influenza A Virus, H3N2 Subtype / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D007564:Japan; D008969:Molecular Sequence Data; D009976:Orthomyxoviridae Infections / Q000662:veterinary* / Q000821:virology; D012367:RNA, Viral / Q000235:genetics; D016865:Reassortant Viruses / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D013552:Swine; D013553:Swine Diseases / Q000821:virology*
chemical_list: D012367:RNA, Viral