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Volume 32, Number 10—October 2026

Dispatch

Detection of Divergent Highly Pathogenic Avian Influenza A(H5N1) Clade 2.3.4.4b Virus, São Paulo, Brazil, 2025

Jansen de AraujoComments to Author , Luciano M. Thomazelli, Thomas P. Fabrizio, Gustavo O. Fenner, Erick G. Dorlass, Ana K.A. Eisen, Viviane F. Botosso, Marcello S. Nardi, Caroline C. Aires, Sergio M.N. Teixeira, Roberta M. de Azevedo, Mayra H. Frediani, Tatiana Ometto, Mário G.L. Barboza, Edmarcia E. de Souza, Carsten Wrenger, Richard J. Webby, and Edison L. Durigon
Author affiliation: University of São Paulo, São Paulo, Brazil (J. de Araujo, L.M. Thomazelli, G.O. Fenner, E.G. Dorlass, A.K.A. Eisen, M.G.L. Barboza, E.E. de Souza, C. Wrenger, E.L. Durigon); St. Jude Children’s Research Hospital, Memphis, Tennessee, USA (T.P. Fabrizio, R.J. Webby); Hospital Israelita Albert Einstein, São Paulo (E.G. Dorlass); Instituto Butantan, São Paulo (V.F. Botosso); Centro de Manejo e Conservação de Animais Silvestres, São Paulo (M.S. Nardi, C.C. Aires, S.M.N. Teixeira, R.M. de Azevedo, M.H. Frediani); Centro Nacional de Pesquisa em Energia e Materiais, Campinas, Brazil (T. Ometto); Institut Pasteur de São Paulo, São Paulo (C. Wrenger, E.L. Durigon).

Main Article

Figure 3

Phylogenetic tree of hemagglutinin gene from divergent highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus, São Paulo, Brazil, 2025. Maximum-likelihood phylogenetic tree (left) showing alignment of global hemagglutinin gene sequences. Inset (right) shows closest related hemagglutinin gene sequences to those from this study denoted by asterisks (*). Scale bar indicates nucleotide substitutions per site.

Figure 3. Phylogenetic tree of hemagglutinin gene from divergent highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus, São Paulo, Brazil, 2025. Maximum-likelihood phylogenetic tree (left) showing alignment of global hemagglutinin gene sequences. Inset (right) shows closest related hemagglutinin gene sequences to those from this study denoted by asterisks (*). Scale bar indicates nucleotide substitutions per site.

Main Article

Page created: July 16, 2026
Page updated: September 28, 2026
Page reviewed: September 28, 2026
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