Sep 2026· Influenza and Other Respiratory Viruses· Vol 20· 0 citations· 36 references
Medicine
Abstract
The high‐pathogenicity avian influenza (HPAI) viruses represent a main threat to animal and human health, poultry productivity, and ecosystems. The newly evolved A(H5N1) clade 2.3.4.4b has become a worldwide concern for its expanding multihost ecology, including poultry and a wide range of mammalian species.
In 2025, we detected highly pathogenic avian influenza H5N1 virus in dead waterfowl at Ibirapuera Park, São Paulo, Brazil. Genomic characterization indicated a reassortant virus that emerged from locally circulating low pathogenicity avian influenza viruses and highly pathogenic North American lineages. Our results hig...
J. de Araújo, L. Thomazelli, Thomas P. Fabrizio et al.· Emerging Infectious Diseases· 0 citations
H5Nx goose/Guangdong (Gs/GD) lineage highly pathogenic avian influenza (HPAI) viruses pose a significant public health threat due to their global spread, mutation accumulation, and expanding host range. The descendant clade 2.3.4.4b has been causing widespread infections in birds and increasing spillover events in mamm...
G. D’Annunzio, Ana Moreno, Giovanni Tosi et al.· Influenza and Other Respirat...· 0 citations
In 2025, highly pathogenic avian influenza A(H5N1) virus was detected in a poultry flock in Illinois, USA. Quantitative reverse transcription PCR, sequencing, and histopathology on cat and rat samples from the farm showed multiple positive tissues and high sequence identity to an avian isolate. Small mammals might cont...
Suzanna M. Storms, Jade Rathmann, Lynette Hemker et al.· Emerging Infectious Diseases· 0 citations
We identified highly pathogenic avian influenza virus subtype H5 in stranded dolphins along the coastline of Brazil during 2023–2025. Infected animals included species classified as vulnerable or endangered. Our results highlight the need for ongoing surveillance of cetaceans susceptible to viral infections, which pose...
A. S. Melgarejo, Maurício Tavares, D. B. de Amorim et al.· Emerging Infectious Diseases· 0 citations
Highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus continues to cause animal outbreaks and sporadic zoonotic infections. In a mouse model of lethal influenza disease, we compared oseltamivir, baloxavir, and molnupiravir monotherapies with 2-drug combinations. Baloxavir-based combinations improved survival,...
S. Min, Ju Ryeong Lee, Beom Kyu Kim et al.· Emerging Infectious Diseases· 0 citations
Two incursions of high pathogenicity avian influenza (HPAI) A(H5N1) clade 2.3.4.4b in vagrant birds were identified in the Hunter New England region of New South Wales, Australia on 28 June 2026 and 10 July 2026. These were the first detections of the virus in New South Wales and occurred shortly after the first Austra...