著者

Kosuke SODA Hirohisa MEKATA Tatsufumi USUI Hiroshi ITO Yuto MATSUI Kentaro YAMADA Tsuyoshi YAMAGUCHI Toshihiro ITO

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.23-0121, (Released:2023-09-26)

被引用文献数

1

---

In the winter of 2021–2022, multiple subtypes (H5N8 and H5N1) of high pathogenicity avian influenza viruses (HPAIVs) were confirmed to be circulating simultaneously in Japan. Here, we phylogenetically and antigenically analyzed HPAIVs that were isolated from infected wild birds, an epidemiological investigation of affected poultry farms, and our own active surveillance study. H5 subtype hemagglutinin (HA) genes of 32 representative HPAIV isolates were classified into clade 2.3.4.4b lineage and subsequently divided into three groups (G2a, G2b, and G2d). All H5N8 HPAIVs were isolated in early winter and had HA genes belonging to the G2a group. H5N1 HPAIVs belong to the G2b and G2d groups. Although G2b viruses were widespread throughout the season, G2d viruses endemically circulated in Northeast Japan after January 2022. Deep sequence analysis showed that the four HPAIVs isolated at the beginning of winter had both N8 and N1 subtypes of neuraminidase genes. Environmental water-derived G2a HPAIV, A/water/Tottori/NK1201-2/2021 (H5N8), has unique polymerase basic protein 1 and nucleoprotein genes, similar to those of low pathogenicity avian influenza viruses (LPAIVs). These results indicate that multiple H5 HPAIVs and LPAIVs disseminated to Japan via transboundary winter migration of wild birds, and HPAIVs with novel gene constellations could emerge in these populations. Cross-neutralization test revealed that G2a H5N8 HPAIVs were antigenically distinct from a G2b H5N1 HPAIV, suggesting that antibody pressure in wild birds was involved in the transition of the HPAIV groups during the season.

著者

Kosuke SODA Tatsufumi USUI Tsuyoshi YAMAGUCHI Toshihiro ITO

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.23-0124, (Released:2023-06-16)

被引用文献数

1

---

During the 2020–2021 winter, Eurasian countries experienced large outbreaks caused by the clade 2.3.4.4b H5N8 subtype high pathogenicity avian influenza viruses (HPAIVs) in the wild bird populations. At least seven gene constellations have been found in the causal HPAIVs. When and where the various HPAIVs emerged remains unclear. Here, we successfully cloned H5N8 HPAIVs with multiple gene constellations from a tracheal swab of a dead mallard found at its wintering site in Japan in January 2021. According to their phylogeny, the bird was most likely co-infected with the E2 and E3 genotype clade 2.3.4.4b HPAIVs. The result indicates that feral waterbirds can be infected with multiple HPAIVs, and shed an HPAIV with novel gene constellation in Southern wintering sites.

著者

Hirohito OGAWA Rajesh CHAHOTA Kenji OHYA Tsuyoshi YAMAGUCHI Hideto FUKUSHI

出版者

公益社団法人 日本獣医学会

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.12-0367, (Released:2012-11-12)

被引用文献数

2 7

---

Beak and feather disease virus (BFDV) is a causative agent of psittacine beak and feather disease (PBFD), which shows a characteristic feather disorder in psittacine birds. In the present study, the subclinical infection rate of PBFD in imported and domestically bred psittacine birds was investigated by polymerase chain reaction. As a result, 126 of 402 birds (31.3 %) were found to be BFDV positive. The DNA sequences of the part of open reading frame (ORF) C1 were determined for 16 BFDV-positive randomly selected samples. One of 16 samples was found to have a mixed infection, and 5 different BFDV sequences were obtained from a single African grey parrot. In phylogenic analysis, almost BFDV sequences included in each genetic cluster of phylogenic tree belonged to the same psittacine subfamily. BFDV derived from African grey parrot was closely related to the BFDV derived from cockatoos by way of exception. The natural habitat of the African grey parrot and cockatoos is different, therefore the possibility of interspecies cross infection through the bird trade is suggested from the exceptional BFDV sequences.