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Genesis and Spread of Novel Highly Pathogenic Avian Influenza A(H5N1) Clade 2.3.4.4b Virus Genotype EA-2023-DG Reassortant, Western Europe
Steven Van Borm
, Ann Kathrin Ahrens, Claudia Bachofen, Ashley C. Banyard, Cathrine Arnason Bøe, François-Xavier Briand, Zuzana Dirbakova, Marc Engelsma, Alice Fusaro, Evelien Germeraad, Britt Gjerset, Béatrice Grasland, Frank Harders, Pierre Hostyn, Ari Kauppinen, Bénédicte Lambrecht, Benjamin C. Mollett, Isabella Monne, Alexander Nagy, Anne Pohlmann, Daniel Polzer, Scott M. Reid, Sandra Revilla-Fernandez, Mieke Steensels, Michaela Stätter, Edyta Swieton, Niina Tammiranta, Michele Wyler, Bianca Zecchin, Siamak Zohari, and Simon Dellicour
Author affiliation: Avian Virology and Immunology Unit, Sciensano, Brussels, Belgium (S. Van Borm, P. Hostyn, B. Lambrecht, M. Steensels); Institute of Diagnostic Virology, Friedrich Loeffler Institut, Greifswald-Insel Riems, Germany (A.K. Ahrens, A. Pohlmann); Institute of Virology and Immunology, Federal Department of Home Affairs, Mittelhäusern, Switzerland (C. Bachofen, M. Wyler); World Organisation for Animal Health/Food and Agriculture Organization of the United Nations International Reference Laboratory for Avian Influenza and Newcastle Disease, Animal and Plant Health Agency-Weybridge, Addlestone, UK (A.C. Banyard, B.C. Mollett, S.M. Reid); Norwegian Veterinary Institute, Ås, Norway (C. Arnason Bøe, B. Gjerset); Agence Nationale de Sécurité Sanitaire de l’alimentation, de l’environnement et du travail, Ploufragan-Plouzané-Niort, France (F.-X. Briand, B. Grasland); State Veterinary Institute Department of Animal Health, Zvolen, Slovakia (D. Dirbakova); Wageningen Bioveterinary Research Department of Virology, Lelystad, the Netherlands (M. Engelsma, E. Germeraad, F. Harders); European Reference Laboratory for Avian Influenza and Newcastle Disease, Istituto Zooprofilattico Sperimentale delle Venezie, Padua, Italy (A. Fusaro, I. Monne, B. Zecchin); Finnish Food Authority, Helsinki, Finland (A. Kauppinen, N. Tammiranta); Department of Molecular Biology, State Veterinary Institute Prague, Praha, Czech Republic (A. Nagy); Austrian Agency for Health and Food Safety, Institute for Veterinary Disease Control, Mödling, Austria (D. Polzer, S. Revilla-Fernandez, M. Stätter); National Veterinary Research Institute Department of Research Support, Puławy, Poland (E. Swieton); Swedish Veterinary Agency Department of Microbiology, Uppsala, Sweden (S. Zohari); Spatial Epidemiology Lab (SpELL), Université Libre de Bruxelles, Brussels, Belgium (S. Dellicour); Laboratory for Clinical and Epidemiological Virology, Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, Leuven, Belgium (S. Dellicour); Interuniversity Institute of Bioinformatics in Brussels, Université Libre de Bruxelles, Vrije Universiteit Brussel, Brussels (S. Dellicour)
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Figure 2
Figure 2. Continuous phylogeographic analysis from study of genesis and spread of novel highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus genotype EA-2023-DG reassortant, western Europe. A) Time-scaled maximum clade credibility treeretrieved and annotated from the continuous phylogeographic inference based on analysis of 54 publicly available complete EA-2023-DG genomes and associated sampling metadata from GISAID EpiFlu (http://www.gisaid.org). The tree shows horizontal shaded bars reflecting the 95% highest posterior density (HPD) associated with each internal node age estimate. The tree and HPD estimates are based on 1,000 trees sampled from the posterior distribution of trees and are colored according to time of occurrence; internal nodes are displayed as dots and tip nodes are displayed as squares. Dotted vertical lines correspond to 2-month intervals beginning July 1, 2023. B–F) Phylogeographic reconstruction of EA-2023-DG viral lineages across western Europe. We mapped the MCC tree and 80% HPD regions reflecting the uncertainty related to the Bayesian phylogeographic inference as of June 25, 2024 (B), and for other time points: C) September 1, 2023; D) November 1, 2023; E) January 1, 2024; and F) June 25, 2024. On the maps, the dispersal direction of viral lineages is indicated by the edge curvature in a counterclockwise direction.
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