Volume 28, Number 12—December 2022
Research Letter
Severe Human Case of Zoonotic Infection with Swine-Origin Influenza A Virus, Denmark, 2021
, Lasse S. Vestergaard, Jakob N. Nissen, Sophie J. George, Pia Ryt-Hansen, Charlotte K. Hjulsager, Jesper S. Krog, Marianne N. Skov, Søren Alexandersen, Lars E. Larsen, and Ramona Trebbien
Table
Percentage nucleotide and amino acid identities between influenza A virus from a patient in Denmark (A/Denmark/36/2021), the seasonal vaccine strain, and closely related strains*
| Gene | A/Victoria/2570/2019 | A/swine/Denmark/S19922-5/2021 | A/swine/Denmark/24856-3/2021 | A/swine/Denmark/S22282-5/2021 | A/Denmark/1/2021 |
|---|---|---|---|---|---|
| Pairwise nucleotide identity to A/Denmark/36/2021, % | |||||
| PB2 | 94.8 | 99.4 | 98.9 | 99.4 | 96.1 |
| PB1 | 94.7 | 99.5 | 98.9 | 99.3 | 93.6 |
| PA | 95.2 | 99.8 | 99.3 | 99.6 | 96.8 |
| HA | 90.7 | 99.0 | 98.7 | 72.6 | 89.9 |
| NP | 95.3 | 99.7 | 98.9 | 99.4 | 96.4 |
| NA | 86.9 | 99.3 | 98.7 | n/a | 87.0 |
| MP | 95.2 | 99.6 | 99.6 | 92.6 | 95.3 |
| NS |
79.7 |
99.9 |
99.1 |
99.6 |
92.8 |
| Pairwise amino acid identity to A/Denmark/36/2021, % | |||||
| PB2 | 97.2 | 99.6 | 99.5 | 99.6 | 97.9 |
| PB1 | 97.6 | 99.9 | 99.5 | 99.9 | 97.9 |
| PA | 97.6 | 99.9 | 99.3 | 99.4 | 98.3 |
| PA-X | 96.6 | 100 | 100 | 100 | 98.7 |
| HA | 90.3 | 98.8 | 98.6 | 75.8 | 88.5 |
| NP | 98.2 | 100 | 99.6 | 99.8 | 98.4 |
| NA | 85.1 | 98.9 | 97.4 | n/a | 86.1 |
| M1 | 97.6 | 100 | 100 | 97.6 | 97.6 |
| M2 | 94.9 | 100 | 100 | 90.7 | 93.8 |
| NS1 | 72.4 | 99.6 | 98.3 | 99.1 | 91.7 |
| NEP | 85.1 | 100 | 100 | 100 | 95 |
*Seasonal vaccine strain, A/Victoria/2570/2019 (GISAID isolate no. EPI_ISL_517733; Appendix 2; strains from passive surveillance Denmark: A/swine/Denmark/S19922–5/2021 (GenBank accession nos. ON716251–8), A/swine/Denmark/24856-3/2021 (accession nos. ON716275–82), A/Denmark/S22282-5/2021 (accession nos. ON716267–74); and another recent variant case found in Denmark (A/Denmark/1/2021; GISAID isolate no. EPI_ISL_909652) (4). The A/swine/Denmark/S22282-5/2021 is of the H1N2 subtype and therefore no percentage similarity is reported to the neuraminidase gene segment and protein of this strain. HA, hemagglutinin; MP/M1/M2, matrix protein 1/2; NA, neuraminidase; n/a, not applicable; NEP, nuclear export protein; NP, nucleoprotein; NS/NS1, nonstructural protein; PA, polymerase acidic protein; PB1/2, polymerase basic protein 1/2.
References
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