Pathogenicity of H5 highly pathogenic avian influenza virus in rooks (Corvus frugilegus). Issue 3 (3rd May 2020)

• Record Type: Journal Article
• Authors: Soda, Kosuke; Tomioka, Yukiko; Usui, Tatsufumi; Ozaki, Hiroichi; Yamaguchi, Tsuyoshi; Ito, Toshihiro
• Is Part Of: Avian pathology. Volume 49:Issue 3(2020)
• Page Start: 261
• Page End: 267
• Publication Date: 2020-05-03
• Subjects: Avian influenza -- rook -- Corvus frugilegus -- crane -- Grus monacha -- Grus vipio -- H5 -- HPAI; Poultry -- Diseases -- Periodicals; Birds -- Diseases -- Periodicals; 571.918
• DOI: 10.1080/03079457.2020.1724876
• Languages: English
• ISSNs: 0307-9457

Abstract

ABSTRACT: Rooks ( Corvus frugilegus ) are considered migratory crows in Japan. Some rooks share a wintering site in the Izumi plain in Kagoshima Prefecture with hooded cranes ( Grus monacha ) and white-necked cranes ( Grus vipio ), which are designated as "endangered" in the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. Highly pathogenic avian influenza (HPAI), caused by H5 subtype viruses, has recently been reported in these crane species in Japan, in conjunction with a massive decrease in their population. In the present study, the pathogenicity of HPAI virus was assessed in rooks to evaluate the likelihood that they are a source of infections in other bird species. One of four rooks intranasally inoculated with A/mandarin duck/Miyazaki/22M807-1/2011 (H5N1) died at 10 days post-inoculation (d.p.i.). The other three rooks exhibited seroconversion but no clinical signs. All the rooks had shed virus by the oral route at <10 3 50% egg infectious dose/ml until 7 d.p.i. Virus was also recovered from multiple tissues of the rook that succumbed to the infection. These results suggest that rooks are susceptible to infection with H5 HPAI viruses, leading to prolonged viral shedding. The rooks shed the virus at low titres however, indicating that they are likely to function as transmission vectors in wintering bird flocks. The rooks exhibited clear antibody responses against the H5 HPAI virus, and thus serological surveillance of them in the field should be helpful for assessing viral pervasion into the habitats of crane species.