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Volume 31, Number 6—June 2025

Dispatch

Highly Pathogenic Avian Influenza A(H5N1) in Wild Birds and a Human, British Columbia, Canada, 2024

Chelsea G. HimsworthComments to Author , Jessica M. Caleta, Agatha N. Jassem, Kevin C. Yang, James E.A. Zlosnik, John R. Tyson, Laurie Wilson, Kevin S. Kuchinski, Jolene Giacinti, Megan Willie, Tony D. Redford, Maeve Winchester, Caeley Thacker, Yohannes Berhane, Theresa Burns, Natalie Prystajecky, and Shannon L. Russell
Author affiliation: British Columbia Ministry of Agriculture and Food, Abbotsford, British Columbia, Canada (C.G. Himsworth, T.D. Redford, T. Burns); British Columbia Centre for Disease Control, Vancouver, British Columbia, Canada (J.M. Caleta, A.N. Jassem, K.C. Yang, J.E.A. Zlosnik, J.R. Tyson, K.S. Kuchinski, N. Prystajecky, S.L. Russell); Canadian Wildlife Service–Environment and Climate Change Canada, Delta, British Columbia, Canada (L. Wilson, M. Willie); Environment and Climate Change Canada, Ottawa, Ontario, Canada (J. Giacinti); British Columbia Ministry of Water, Land and Resource Stewardship, Nanaimo, British Columbia, Canada (M. Winchester, C. Thacker); Canadian Food Inspection Agency, Winnipeg, Manitoba, Canada (Y. Berhane)

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Table

Reassortant classification and genotypic characterization of clade 2.3.4.4 b viruses in a study of highly pathogenic avian influenza A(H5N1) in wild birds and a human, British Columbia, Canada, 2024*

GenoFLU genotype† Genotype assignment by influenza A segment*
 Outbreak wave‡
HA NA M NP NS PA PB1 PB2
B2.1 EA1 EA1 EA1 Am1.1 EA1 EA1 EA1 Am1.2 Wave 1
B3.2 EA1 EA1 EA1 Am1.4.1 Am1.1 EA1 Am1.2 Am2.1 Waves 1–3
B3.6 EA1 EA1 EA1 Am1.4.1 Am1.1 EA1 Am4 Am5 Wave 3
B3.10 EA1 EA1 EA1 Am4 Am1.1 EA1 Am4 Am5 Wave 3
B3.1 EA1 EA1 EA1 Am1.4.1 EA1 EA1 EA1 Am2.1 Wave 1
B4.1 EA1 EA1 EA1 Am1.3 EA1 EA1 EA1 Am2.2 Waves 1–3
A3 EA3 EA3 EA3 EA3 EA3 EA3 EA3 EA3 Waves 1–4
D1.1 EA3 Am4N1 EA3 Am13 EA3 Am4 EA3 Am24 Wave 4
B3.13 EA1 EA1 EA1 Am8 Am1.1 EA1 Am4 Am2.2 US cattle genotype (for context only)

*Data show viruses detected in British Columbia, Canada, during September 2021–November 2024 contextualized by the US cattle virus genotype B3.13 identified in 2024. Am, North American lineage; EA, Eurasian lineage; HA, hemagglutinin; M, matrix; NA, neuaminidase; NP, nucleoprotein; NS, nonstructural; PA, polymerase acidic; PB, polymerase basic. †Genotype assignment from GenoFlu pipeline (2). ‡Wave 1, April–Sept 2022; wave 2, Sept 2022–Aug 2023; wave 3, Sept 2023–Aug 2024; wave 4, Sept 2024–November 2024.

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References
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