title: Highly pathogenic avian influenza (H5N1) in the commercial domestic ducks of South Korea.
abstract: The present study reports the clinical, virological and pathological findings observed in a natural outbreak of highly pathogenic avian influenza in farmed commercial ducks. The ducks developed clinical signs, including mild respiratory distress, depression, mild diarrhoea, loss of appetite and increasing mortality (up to 12%). At necropsy, multifocal mottled necrosis was commonly found in the pancreas with splenomegaly, hepatomegaly, and swollen kidneys. Microscopically, there was necrotized pancreatitis and hepatitis, and lymphocytic meningoencephalitis and myocarditis. Influenza viral antigen was demonstrated in areas closely associated with histopathological lesion. Avian influenza virus was isolated from the caecal tonsil, faeces, and kidney of the domestic ducks. The isolated virus was identified as a highly pathogenic H5N1, with a haemagglutinin proteolytic cleavage site deduced amino acid sequence of ... QREKRKKR/GLFGAIAG ... In order to determine the pathogenicity of the isolate, eight 6-week-old specific pathogen free chickens were inoculated intravenously with the virus, and all birds died within 24 h after inoculation. This is the first report of an outbreak of highly pathogenic avian influenza with clinical signs in commercial domestic ducks in South Korea.
authors.affiliation: National Veterinary Research & Quarantine Service, MAF, 480, Anyang, 430-824, Korea.
authors.forename: Yong-Kuk
authors.initials: YK
authors.lastname: Kwon
authors.forename: Seong-Joon
authors.initials: SJ
authors.lastname: Joh
authors.forename: Min-Chul
authors.initials: MC
authors.lastname: Kim
authors.forename: Haan-Woo
authors.initials: HW
authors.lastname: Sung
authors.forename: Youn-Jeong
authors.initials: YJ
authors.lastname: Lee
authors.forename: Jun-Gu
authors.initials: JG
authors.lastname: Choi
authors.forename: Eun-Kyoung
authors.initials: EK
authors.lastname: Lee
authors.forename: Jae-Hong
authors.initials: JH
authors.lastname: Kim
mesh_terms: D000818:Animals; D004196:Disease Outbreaks / Q000662:veterinary*; D004372:Ducks / Q000821:virology*; D053124:Influenza A Virus, H5N1 Subtype; D009980:Influenza A virus / Q000145:classification; D005585:Influenza in Birds / Q000453:epidemiology* / Q000473:pathology / Q000821:virology; D007723:Korea / Q000453:epidemiology