Volume 30, Number 6—June 2024
Dispatch
Concurrent Infection with Clade 2.3.4.4b Highly Pathogenic Avian Influenza H5N6 and H5N1 Viruses, South Korea, 2023
Table 1
Nucleotide sequence identities of gene segments between reassortant clade 2.3.4.4b HPAI H5N6 virus from a duck farm in South Korea, 2023, compared with A/duck/Korea/D448-N6/2023(H5N6) virus and the closest referent in the GISAID database*
| Gene | Virus | GISAID accession no. | % Identity | Sample date | LPIAI or HPAI H5 clade |
|---|---|---|---|---|---|
| PB2 | A/mallard/South_Korea/20X-20/2021(H7N9) | EPI_ISL_6781375 | 98.73 | 2021 Jan 6 | LPAI |
| PB1 | A/large billed_crow/Kanagawa/1403C006/2023(H5N1) | EPI_ISL_17949961 | 99.69 | 2023 Mar 10 | 2.3.4.4b |
| PA | A/common_teal/Amur_region/92b/2020(H6N2) | EPI_ISL_1184535 | 99.58 | 2020 Sep 6 | LPAI |
| HA | A/Mandarin_duck/Korea/WA496/2022(H5N1) | EPI_ISL_15647836 | 99.53 | 2022 Oct 10 | 2.3.4.4b |
| NP | A/gadwall/Novosibirsk_region/3407k/2020(H4N6) | EPI_ISL_1184520 | 98.8 | 2020 Aug 29 | LPAI |
| NA | A/duck/Hunan/S40199/2021(H5N6)† | EPI_ISL_11208196 | 98.62 | 2021 Dec 1 | 2.3.4.4b |
| M | A/Mandarin_duck/Korea/WA496/2022(H5N1) | EPI_ISL_15647836 | 99.8 | 2022 Oct 10 | 2.3.4.4b |
| NS | A/Falcated_duck/South_Korea/JB42–30/2020(H9N2) | EPI_ISL_4072076 | 99.64 | 2020 Feb 19 | LPAI |
*One A/duck/Korea/D448-N6/2023(H5N6) isolate from a wild bird (WA875) and 2 isolates from poultry (D448-N6, D449) had high nucleotide identities among them in all 8 genes: PB2, >99.82%; PB1, >99.78%; PA, >99.86%; HA, >99.82%; NP, >99.87%; NA, >99.86%; M, >99.90%; NS, >99.88%. GISAID, https://www.gisaid.org; HA, hemagglutinin; HPAI, highly pathogenic avian influenza; LPAI, low pathogenicity avian influenza; M, matrix; N, nucleocapsid; NA, neuraminidase; NP, nucleoprotein; NS, nonstructural; PA, polymerase acidic; PB, polymerase basic. †This virus was isolated from bird in poultry market, and all the other viruses compared were from wild birds.