title: Pathology of natural highly pathogenic avian influenza H5N1 infection in wild tufted ducks (Aythya fuligula).
abstract: Highly pathogenic avian influenza (HPAI) subtype H5N1 is an infectious systemic viral disease that results in high morbidity and mortality in poultry, and has been reported in a wide range of wild bird species during the last few years. An outbreak of HPAI H5N1 occurred in wild birds in Sweden in 2006 that affected several duck species, geese, swans, gulls, and raptors. Tufted ducks (Aythya fuligula) accounted for the largest number of positive cases and, therefore, were selected for more in-depth histologic and immunohistochemical evaluations. The main histologic lesions associated with the presence of avian influenza antigen were found in the brain, pancreas, and upper respiratory tract. Other tissues in which influenza antigen was variably found included liver, lung, adrenal glands, kidneys, and peripheral nerve ganglia. The current study describes the pathology and viral tissue targeting of H5N1 by using histology, polymerase chain reaction, and immunohistochemistry, and highlights the range and variation in the presentation of the natural disease in tufted ducks.
authors.affiliation: Department of Pathology and Wildlife Diseases, National Veterinary Institute (SVA), SE75189, Uppsala, Sweden. Caroline.Brojer@sva.se
authors.forename: Caroline
authors.initials: C
authors.lastname: Bröjer
authors.forename: Erik O
authors.initials: EO
authors.lastname: Agren
authors.forename: Henrik
authors.initials: H
authors.lastname: Uhlhorn
authors.forename: Karin
authors.initials: K
authors.lastname: Bernodt
authors.forename: Torsten
authors.initials: T
authors.lastname: Mörner
authors.forename: Désirée S
authors.initials: DS
authors.lastname: Jansson
authors.forename: Roland
authors.initials: R
authors.lastname: Mattsson
authors.forename: Siamak
authors.initials: S
authors.lastname: Zohari
authors.forename: Peter
authors.initials: P
authors.lastname: Thorén
authors.forename: Mikael
authors.initials: M
authors.lastname: Berg
authors.forename: Dolores
authors.initials: D
authors.lastname: Gavier-Widén
mesh_terms: D000818:Animals; D000835:Animals, Wild / Q000821:virology; D000956:Antigens, Viral / Q000032:analysis; D001921:Brain / Q000473:pathology / Q000821:virology; D002988:Cloaca / Q000473:pathology / Q000821:virology; D004372:Ducks / Q000821:virology; D007150:Immunohistochemistry; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics / Q000472:pathogenicity*; D005585:Influenza in Birds / Q000453:epidemiology / Q000473:pathology / Q000821:virology*; D008099:Liver / Q000473:pathology / Q000821:virology; D009474:Neurons / Q000473:pathology / Q000821:virology; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013548:Sweden / Q000453:epidemiology
chemical_list: D000956:Antigens, Viral; D012367:RNA, Viral