TY - JOUR

T1 - Detection of New H5N1 High Pathogenicity Avian Influenza Viruses in Winter 2021–2022 in the Far East, Which Are Genetically Close to Those in Europe

AU - Isoda, Norikazu

AU - Onuma, Manabu

AU - Hiono, Takahiro

AU - Sobolev, Ivan

AU - Lim, Hew Yik

AU - Nabeshima, Kei

AU - Honjyo, Hisako

AU - Yokoyama, Misako

AU - Shestopalov, Alexander

AU - Sakoda, Yoshihiro

N1 - Funding Information: This project was partially funded by the Science and Technology Research Partnership for Sustainable Development (SATREPS) grant number [JP22jm0110019]. This project was mainly supported by the Ministry of Environment, Japan, which assisted with the official diagnosis fee of HPAIVs in wild birds. This work was partially supported by the Japan Science and Technology Agency SPRING grant number JPMJSP2119 and the World-Leading Innovative and Smart Education (WISE) Program (1801) from the Ministry of Education, Culture, Sports, Science and Technology, Japan. Publisher Copyright: © 2022 by the authors.

PY - 2022/10

Y1 - 2022/10

N2 - Many high pathogenicity avian influenza (HPAI) cases in wild birds due to H5N1 HPAI virus (HPAIV) infection were reported in northern Japan in the winter of 2021–2022. To investigate the epidemiology of HPAIVs brought to Japan from surrounding areas, a genetic analysis of H5 HPAIVs isolated in northern Japan was performed, and the pathogenicity of the HPAIV in chickens was assessed by experimental infection. Based on the genetic analysis of the hemagglutinin gene, pathogenic viruses detected in northern Japan as well as one in Sakhalin, the eastern part of Russia, were classified into the same subgroup as viruses prevalent in Europe in the same season but distinct from those circulating in Asia in winter 2020–2021. High identities of all eight segment sequences of A/crow/Hokkaido/0103B065/2022 (H5N1) (Crow/Hok), the representative isolates in northern Japan in 2022, to European isolates in the same season could also certify the unlikeliness of causing gene reassortment between H5 HPAIVs and viruses locally circulating in Asia. According to intranasal challenge results in six-week-old chickens, 50% of the chicken-lethal dose of Crow/Hok was calculated as 104.5 times of the 50% egg-infectious dose. These results demonstrated that the currently prevalent H5 HPAIVs could spread widely from certain origins throughout the Eurasian continent, including Europe and the Far East, and implied a possibility that contagious viruses are gathered in lakes in the northern territory via bird migration. Active monitoring of wild birds at the global level is essential to estimate the geographical source and spread dynamics of HPAIVs.

AB - Many high pathogenicity avian influenza (HPAI) cases in wild birds due to H5N1 HPAI virus (HPAIV) infection were reported in northern Japan in the winter of 2021–2022. To investigate the epidemiology of HPAIVs brought to Japan from surrounding areas, a genetic analysis of H5 HPAIVs isolated in northern Japan was performed, and the pathogenicity of the HPAIV in chickens was assessed by experimental infection. Based on the genetic analysis of the hemagglutinin gene, pathogenic viruses detected in northern Japan as well as one in Sakhalin, the eastern part of Russia, were classified into the same subgroup as viruses prevalent in Europe in the same season but distinct from those circulating in Asia in winter 2020–2021. High identities of all eight segment sequences of A/crow/Hokkaido/0103B065/2022 (H5N1) (Crow/Hok), the representative isolates in northern Japan in 2022, to European isolates in the same season could also certify the unlikeliness of causing gene reassortment between H5 HPAIVs and viruses locally circulating in Asia. According to intranasal challenge results in six-week-old chickens, 50% of the chicken-lethal dose of Crow/Hok was calculated as 104.5 times of the 50% egg-infectious dose. These results demonstrated that the currently prevalent H5 HPAIVs could spread widely from certain origins throughout the Eurasian continent, including Europe and the Far East, and implied a possibility that contagious viruses are gathered in lakes in the northern territory via bird migration. Active monitoring of wild birds at the global level is essential to estimate the geographical source and spread dynamics of HPAIVs.

KW - bird migration

KW - genetic profile

KW - H5N1

KW - high pathogenicity avian influenza

KW - wild birds

KW - Influenza in Birds/epidemiology

KW - Virulence

KW - Influenza A Virus, H5N1 Subtype

KW - Phylogeny

KW - Influenza A virus/genetics

KW - Animals, Wild

KW - Animals

KW - Europe/epidemiology

KW - Far East/epidemiology

KW - Chickens

KW - Hemagglutinins

KW - Seasons

UR - http://www.scopus.com/inward/record.url?scp=85140841887&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/d99ff336-abbe-39bf-ad8c-75149197cfdc/

U2 - 10.3390/v14102168

DO - 10.3390/v14102168

M3 - Article

C2 - 36298722

AN - SCOPUS:85140841887

VL - 14

JO - Viruses

JF - Viruses

SN - 1999-4915

IS - 10

M1 - 2168

ER -