title: Low pathogenic H7 subtype avian influenza viruses isolated from domestic ducks in South Korea and the close association with isolates of wild birds.
abstract: We characterized low pathogenic avian influenza (LPAI) viruses of the H7 subtype that were isolated from domestic ducks and wild birds in South Korea from 2008 to 2011. A total of 20 H7 viruses were collected from live-bird markets (LBMs), duck farms and wild-bird habitats using avian influenza (AI) surveillance and epidemiological approaches. A phylogenetic analysis of the H7 viruses that were isolated from domestic ducks and wild birds demonstrated that they were separated into 12 genotypes (A-D and Wb-1-8, respectively), indicating genetic diversity. These H7 viruses were related to the recently isolated Eurasian LPAI H7 viruses and various influenza viruses that are circulating in Asia, including southern China and South Korea. The same genotype was not found between domestic poultry and wild-bird isolates; however, most of the H7 viruses in poultry (genotypes B and C) were closely related to the H7 virus isolated from a wild bird (genotype Wb-3). Animal-challenge studies revealed that certain H7 AI viruses replicated well only in chickens or ducks depending on the genotype, indicating that the pathogenicity of H7 viruses has the potential to be altered due to multiple reassortments, and these viruses can potentially expand their host range. Our results are evidence of abundant and frequent reassortment between H7 viruses in poultry and wild birds and emphasize the continuing need to monitor the evolutionary genetics of the influenza virus in poultry and wild birds.
authors.affiliation: Animal Disease Diagnosis Division, Animal, Plant and Fisheries Quarantine and Inspection Agency, 175 Anyangro, Manangu, Anyangsi, Gyeonggido 430-757, Republic of Korea.
authors.forename: Hye-Ryoung
authors.initials: HR
authors.lastname: Kim
authors.affiliation: Animal Disease Diagnosis Division, Animal, Plant and Fisheries Quarantine and Inspection Agency, 175 Anyangro, Manangu, Anyangsi, Gyeonggido 430-757, Republic of Korea.
authors.forename: Choi-Kyu
authors.initials: CK
authors.lastname: Park
authors.affiliation: Avian Disease Division, Animal, Plant and Fisheries Quarantine and Inspection Agency, 175 Anyangro, Manangu, Anyangsi, Gyeonggido 430-757, Republic of Korea.
authors.forename: Youn-Jeong
authors.initials: YJ
authors.lastname: Lee
authors.affiliation: Animal Disease Diagnosis Division, Animal, Plant and Fisheries Quarantine and Inspection Agency, 175 Anyangro, Manangu, Anyangsi, Gyeonggido 430-757, Republic of Korea.
authors.forename: Jae-Ku
authors.initials: JK
authors.lastname: Oem
authors.affiliation: Avian Disease Division, Animal, Plant and Fisheries Quarantine and Inspection Agency, 175 Anyangro, Manangu, Anyangsi, Gyeonggido 430-757, Republic of Korea.
authors.forename: Hyun-Mi
authors.initials: HM
authors.lastname: Kang
authors.affiliation: Avian Disease Division, Animal, Plant and Fisheries Quarantine and Inspection Agency, 175 Anyangro, Manangu, Anyangsi, Gyeonggido 430-757, Republic of Korea.
authors.forename: Jun-Gu
authors.initials: JG
authors.lastname: Choi
authors.affiliation: Animal Disease Diagnosis Division, Animal, Plant and Fisheries Quarantine and Inspection Agency, 175 Anyangro, Manangu, Anyangsi, Gyeonggido 430-757, Republic of Korea.
authors.forename: O-Soo
authors.initials: OS
authors.lastname: Lee
authors.affiliation: Animal Disease Diagnosis Division, Animal, Plant and Fisheries Quarantine and Inspection Agency, 175 Anyangro, Manangu, Anyangsi, Gyeonggido 430-757, Republic of Korea.
authors.forename: You-Chan
authors.initials: YC
authors.lastname: Bae
mesh_terms: D000818:Animals; D000835:Animals, Wild / Q000821:virology; D046090:Anseriformes / Q000821:virology; D004372:Ducks; D005838:Genotype; D009980:Influenza A virus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity; D005585:Influenza in Birds / Q000821:virology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D011201:Poultry Diseases / Q000821:virology*; D056910:Republic of Korea; D014774:Virulence