WHO surveillance confirms susceptibility of influenza viruses to antivirals
The vast majority of seasonal and zoonotic influenza viruses tested remained susceptible to neuraminidase inhibitors (NAIs) and the polymerase inhibitor, baloxavir marboxil.
Emergence and spread of NA-I223V and NA-S247N double-mutant A(H1N1)pdm09 influenza viruses with reduced oseltamivir susceptibility in the Netherlands and beyond, 2023 to 2026
These findings underscore the need for ongoing genomic and phenotypic monitoring of antiviral susceptibility.
First detection of avian influenza (H5) in poultry in Suriname; multidistrict spread under investigation
The confirmation of influenza A(H5) in a commercial broiler flock represents Suriname's first detected incursion of this pathogen.
Positive case of avian influenza in backyard poultry in Los Ríos Region, Chile
The Agricultural and Livestock Service (SAG) confirmed a positive case of highly pathogenic avian influenza (HPAI) H5N1 in backyard birds in the commune of Corral in the Los Ríos region.
Avian influenza amplified age-related mortality in a long-lived seabird
HPAI-related mortality increased from approximately 5–10% in young breeders to more than 40% in the oldest individuals.
H5N1 Clade 2.3.4.4b Infections in Domestic Cats During an Avian Influenza Outbreak in Italy: Implications for One Health Surveillance
This report documents the first fatal case of highly pathogenic avian influenza virus (HPAIV) H5N1 clade 2.3.4.4b infection in a domestic cat in Italy, detected in early January 2025.
Genomic detection of highly pathogenic avian influenza H5N1 in Antarctic seabirds reveals connectivity with South American viral lineages
Phylogenetic analysis indicates a direct connectivity between Antarctic seabirds and the broader H5N1 transmission network.
Avian Influenza Weekly Update # 1063: 25 September 2026
From 18 to 24 September 2026, no new case of human infection with avian influenza A(H5N1) virus was reported to WHO in the Western Pacific Region.
