Pathologic Findings and Viral Antigen Distribution During Natural Infection of Ring-Necked Pheasants With H5N2 Highly Pathogenic Avian Influenza Virus A.
Highly pathogenic avian influenza (HPAI) is a major viral disease of poultry characterized by acute onset, systemic infection, and rapid death. In January 2015, H5N2 HPAI was identified by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and gene sequencing as the cause of rapid death in 40 of 390 ring-necked pheasants (approximately 10% mortality), raised in a game bird farm in Washington State. We report clinicopathologic findings and viral antigen distribution in pheasants that died during the outbreak. Affected birds were depressed with reluctance to move, ruffled feathers, and drooping heads. Congestion of the cerebellar meningeal blood vessels was the only consistent gross pathologic finding. Meningoencephalitis with vasculitis and necrosis in the spleen and heart were the major microscopic lesions in the birds. Viral antigen was consistently detected in the brain, heart, and ovary with variable presence in other organs.
1 Department of Veterinary Microbiology and Pathology and Washington Animal Disease Diagnostic Laboratory, Washington State University, Pullman, WA, USA.
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Ajithdoss
2 USDA APHIS VS National Services Veterinary Laboratories, Ames, IA, USA.
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Torchetti
3 Washington State Department of Agriculture, Olympia, WA, USA.
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Badcoe
1 Department of Veterinary Microbiology and Pathology and Washington Animal Disease Diagnostic Laboratory, Washington State University, Pullman, WA, USA.
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Bradway
1 Department of Veterinary Microbiology and Pathology and Washington Animal Disease Diagnostic Laboratory, Washington State University, Pullman, WA, USA.
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Baszler
D000818:Animals; D000956:Antigens, Viral / Q000302:isolation & purification*; D004372:Ducks; D005260:Female; D046094:Galliformes / Q000821:virology*; D053125:Influenza A Virus, H5N2 Subtype / Q000302:isolation & purification* / Q000472:pathogenicity; D005585:Influenza in Birds / Q000401:mortality / Q000473:pathology / Q000821:virology*; D008297:Male
D000956:Antigens, Viral
H5N2; Phasianus colchicus; avian influenza virus; common pheasant; immunohistochemistry; pathology