title: Corneal Opacity in Domestic Ducks Experimentally Infected With H5N1 Highly Pathogenic Avian Influenza Virus.
abstract: Domestic ducks can be a key factor in the regional spread of H5N1 highly pathogenic avian influenza (HPAI) virus in Asia. The authors performed experimental infections to examine the relationship between corneal opacity and H5N1 HPAI virus infection in domestic ducks (Anas platyrhyncha var domestica). A total of 99 domestic ducks, including 3 control birds, were used in the study. In experiment 1, when domestic ducks were inoculated intranasally with 2 H5N1 HPAI viruses, corneal opacity appeared more frequently than neurologic signs and mortality. Corneal ulceration and exophthalmos were rare findings. Histopathologic examinations of the eyes of domestic ducks in experiment 2 revealed that corneal opacity was due to the loss of corneal endothelial cells and subsequent keratitis with edema. Influenza viral antigen was detected in corneal endothelial cells and some other ocular cells by immunohistochemistry. Results suggest that corneal opacity is a characteristic and frequent finding in domestic ducks infected with the H5N1 HPAI virus. Confirming this ocular change may improve the detection rate of infected domestic ducks in the field.
authors.affiliation: National Institute of Animal Health, Tsukuba, Japan yyu@affrc.go.jp.
authors.forename: Y
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: National Institute of Animal Health, Tsukuba, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Nakamura
authors.affiliation: National Institute of Animal Health, Tsukuba, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yamada
authors.affiliation: National Institute of Animal Health, Tsukuba, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Mase
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000032:analysis*; D003318:Corneal Opacity / Q000473:pathology* / Q000821:virology; D004372:Ducks; D053124:Influenza A Virus, H5N1 Subtype / Q000472:pathogenicity*; D005585:Influenza in Birds / Q000473:pathology* / Q000821:virology
chemical_list: D000956:Antigens, Viral
keywords: H5N1 subtype; corneal opacity; domestic duck; eye; highly pathogenic avian influenza; histopathology; immunohistochemistry