Table 1. The viruses sharing the highest homology with A/wild bird feces/Mongolia/M9-3/2024 (M9-3) and the nucleotide sequence identities of gene segments between the M9-3 and HPAI viruses isolated in Korea and Japan in the 2024–2025 winter season.
| Gene | Virus | Accession number | Range of % identitya |
|---|---|---|---|
| PB2 | A/environment/Kagoshima/KU-24C1/2024 (H5N1) | EPI_ISL_19534183 | 99.65–99.82 |
| PB1 | A/environment/Kagoshima/KU-24-B4/2024 (H5N1) | EPI_ISL_19624046 | 99.74–99.82 |
| PA | A/environment/Kagoshima/KU-24-B4/2024 (H5N1) | EPI_ISL_19624046 | 99.67–99.91 |
| HA | A/environment/Kagoshima/KU-24-B4/2024 (H5N1) | EPI_ISL_19624046 | 99.47–99.82 |
| NP | A/environment/Kagoshima/KU-24C1/2024 (H5N1) | EPI_ISL_19534183 | 99.67–99.87b |
| NA | A/environment/Kagoshima/KU-24-B4/2024 (H5N1) | EPI_ISL_19624046 | 99.43–99.86 |
| M | A/environment/Kagoshima/KU-24-B4/2024 (H5N1) | EPI_ISL_19624046 | 99.80–99.90 |
| NS | A/environment/Kagoshima/KU-24G1/2024 (H5N1) | EPI_ISL_19534185 | 99.40–99.76 |
HPAI, highly pathogenic avian influenza; PB, polymerase basic; PA, polymerase acidic; HA, hemagglutinin; NP, nucleoprotein; NA, neuraminidase; M, matrix; NS, nonstructural.
aNucleotide sequence identity range between M9-3 (EPI_ISL_19825828) and five clade 2.3.4.4b H5N1 HPAI viruses from Korea (A/wild bird/Korea/WF413/2024 (EPI_ISL_19825819), A/Chicken/Korea/C442/2024 (EPI_ISL_19825820)) and Japan (A/environment/Kagoshima/KU-24C1/2024 (EPI_ISL_19534183), A/environment/Kagoshima/KU-24G1/2024 (EPI_ISL_19534185), and A/environment/Kagoshima/KU-24-B4/2024 (EPI_ISL_19624046)).
bA/environment/Kagoshima/KU-24-B4/2024 shared 93.80% nucleotide similarity with M9-3 for NP gene.