ETIDIOH - NEW

Abstract Clade 2.3.4.4b H5N1 high pathogenicity avian influenza virus (HPAIV) has caused a panzootic affecting all continents except Australia , expanding its host range to several mammalian species . In March 2024, H5N1 HPAIV was first detected in dairy cattle and goats in the United States . Over 891 dairy farms across 16 states have tested positive until 25th December 2024, with zoonotic infections reported among dairy workers . This raises concerns about the virus undergoing evolutionary changes in cattle that could enhance its zoonotic potential . The Influenza glycoprotein haemagglutinin (HA) facilitates entry into host cells through receptor binding and pH-induced fusion with cellular membranes. Adaptive changes in HA modulate virus-host cell interactions. This study compared the HA genes of cattle and goat H5N1 viruses with the dominant avian-origin clade 2.3.4.4b H5N1 in the United Kingdom , focusing on receptor binding, pH fusion, and thermostability. All the tested H5N1 viru...

Abstract Emerging infectious diseases are of major concern to animal and human health . Recent emergence of high pathogenicity avian influenza virus (HPAIV) (H5N1 clade 2.3.4.4b) led to substantial global mortality across a range of host species . Co-occurring species showed marked differences in mortality, generating an urgent need for better epidemiological understanding within affected populations. We therefore tested for antibodies , indicative of previous exposure and recovery, and for active viral infection in apparently healthy individuals (n = 350) across five co-occurring seabird species on the Isle of May, Scotland , during 2023, following H5N1 HPAIV associated mortality in the preceding summer. Antibody prevalence to AIV subtypes varied substantially between species, ranging from 1.1% in European shags (Gulosus aristotelis) (to H5 ) to 78.7% in black-legged kittiwakes (Rissa tridactyla) (to H16 or both H13 and H16 ), and between 31 and 41% for three auk species ( H5, H16 or ...