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Volume 31, Number 12—December 2025

Dispatch

Novel Highly Pathogenic Avian Influenza A(H5N1) Virus, Argentina, 2025

Ralph E.T. Vanstreels, Martha I. Nelson, María C. Artuso, Vanina D. Marchione, Luana E. Piccini, Estefania Benedetti, Alvin Crespo-Bellido, Agostina Pierdomenico, Thorsten Wolff, Marcela M. Uhart, and Agustina RimondiComments to Author 
Author affiliation: University of California Davis School of Veterinary Medicine, Davis, California, USA (R.E.T. Vanstreels, M.M. Uhart); National Institutes of Health, Bethesda, Maryland, USA (M.I. Nelson, A. Crespo-Bellido); Servicio Nacional de Sanidad y Calidad Agroalimentaria, Martínez, Buenos Aires, Argentina (M.C. Artuso, V.D. Marchione, L.E. Piccini); Instituto Nacional de Enfermedades Infecciosas Dr. Carlos G. Malbrán, Buenos Aires, Argentina (E. Benedetti); Servicio Nacional de Sanidad y Calidad Agroalimentaria, Buenos Aires, Argentina (A. Pierdomenico); Robert Koch-Institut, Berlin, Germany (T. Wolff, A. Rimondi)

Main Article

Figure 2

Key reassortment and migration events leading to the novel triple reassortant influenza A(H5N1) viruses in February 2025, Argentina. Each box represents 1 of the 8 segments of the influenza A virus genome, numbered in order of longest to shortest length: 1, polymerase basic2; 2, polymerase basic 1; 3, polymerase acidic; 4, hemaggultinin; 5, nucleoprotein; 6, neuraminidase; 7, matrix protein; and 8, nonstructural protein. Curved black arrows indicate the direction of major geographic migration events. Straight black arrows indicate sequential reassortment events of interest. LPAI, low pathogenicity avian influenza.

Figure 2. Key reassortment and migration events leading to the novel triple reassortant influenza A(H5N1) viruses in February 2025, Argentina. Each box represents 1 of the 8 segments of the influenza A virus genome, numbered in order of longest to shortest length: 1, polymerase basic2; 2, polymerase basic 1; 3, polymerase acidic; 4, hemaggultinin; 5, nucleoprotein; 6, neuraminidase; 7, matrix protein; and 8, nonstructural protein. Curved black arrows indicate the direction of major geographic migration events. Straight black arrows indicate sequential reassortment events of interest. LPAI, low pathogenicity avian influenza.

Main Article

Page created: November 17, 2025
Page updated: December 12, 2025
Page reviewed: December 12, 2025
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