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Highly Pathogenic Avian Influenza A(H5N1) Clade 2.3.4.4b Virus Infection in Poultry Farm Workers, Washington, USA, 2024
Yasuko Hatta
1, Juan A. De La Cruz
1, Theresa Murray, Brian Hiatt, Yunho Jang, Julia C. Frederick, Kristine A. Lacek, Juliana C. DaSilva, Dan Cui, Paul Carney, Jimma Liddell, Kay W. Radford, Natasha Burnett, Sabrina Schatzman, Pauline Trinh, Anna Unutzer, Elizabeth A. Pusch, Monique Johnson, Ha T. Nguyen, Benjamin L. Rambo-Martin, Larisa Gubareva, James Stevens, C. Todd Davis, Marie K. Kirby, Allison Black, and Han Di
Author affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, USA (Y. Hatta, J.A. De La Cruz, Y. Jang, J.C. Frederick, K.A. Lacek, J.C. DaSilva, D. Cui, P. Carney, J. Liddell, K.W. Radford, N. Burnett, S. Schatzman, E.A. Pusch, M. Johnson, H.T. Nguyen, B.L. Rambo-Martin, L. Gubareva, J. Stevens, C.T. Davis, M.K. Kirby, H. Di); Washington State Department of Health, Shoreline, Washington, USA (T. Murray, B. Hiatt, P. Trinh, A. Unutzer, A. Black)
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Figure 1

Figure 1. Neighbor-joining phylogenetic trees of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b viruses isolated from poultry farm workers, Washington, USA, 2024. A) Hemagglutinin gene segment; B) neuraminidase gene segment. Green font indicates influenza A(H5N1) D1.1 viruses from Washington; red font indicates prepandemic candidate vaccine virus A/Ezo red fox/Hokkaido/1/2022. Bootstrap values >50, generated from 1,000 replicates, are labeled on branch nodes. Scale bars indicate nucleotide substitutions per site.
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