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Volume 32, Number 8—August 2026

Research

Rapid Expansion of Highly Pathogenic Avian Influenza A(H5N1) Clade 2.3.4.4b Genotype D1.1 Virus across Flyway Regions, North America, Fall 2024

Matthew ScotchComments to Author , Temitope O.C. Faleye, Angelica Urquidez-Negrete, Arvind Varsani, Ann Fan, and Anne Justice-Allen
Author affiliation: Arizona State University, Tempe, Arizona, USA (M. Scotch, T.O.C. Faleye, A. Urquidez-Negrete, A. Varsani); Arizona Game & Fish Department, Phoenix, Arizona, USA (A. Fan, A. Justice-Allen)

Main Article

Figure 3

Most parsimonious pairwise transmission routes from a study of expansion of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b genotype D1.1 virus across flyway regions, North America, fall 2024. Pairs were indicated by Bayes factor results from SpreaD3 (27). Routes with a Bayes factor >3 and posterior probability >0.90 are shown. A thicker arrow indicates greater Bayes factor; node colors represent each discrete flyway. The analysis leveraged sequences from 300 taxa collected during October 2024–March 2025.

Figure 3. Most parsimonious pairwise transmission routes from a study of expansion of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b genotype D1.1 virus across flyway regions, North America, fall 2024. Pairs were indicated by Bayes factor results from SpreaD3 (27). Routes with a Bayes factor >3 and posterior probability >0.90 are shown. A thicker arrow indicates greater Bayes factor; node colors represent each discrete flyway. The analysis leveraged sequences from 300 taxa collected during October 2024–March 2025.

Main Article

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Page created: June 13, 2026
Page updated: July 13, 2026
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