ETIDIOH - NEW

Abstract Yakutia, the largest breeding ground for wild migratory birds in Northeastern Siberia , plays a big role in the global ecology of avian influenza viruses (AIVs). In this study, we present the results of virological surveillance conducted between 2018 and 2023, analyzing 1970 cloacal swab samples collected from 56 bird species . We identified 74 AIVs of H3N6, H3N8, H4N6, H5N3, H7N7, H10N3, and H11N9 subtypes in Anseriformes order. Phylogenetic analysis showed that the isolates belong to the Eurasian lineage and have genetic similarities with strains from East Asia, Europe, and North America. Cluster analysis has demonstrated the circulation of stable AIV genotypes for several years. We assume that Yakutia is an important territory for viral exchange on the migratory routes of migrating birds. In addition, several amino acid substitutions have been found to be associated with increased virulence and adaptation to mammalian hosts , highlighting the potential risk of interspecific...

Abstract Background Avian influenza virus (AIV), a zoonotic pathogen found worldwide , includes multiple subtypes, one of which is the H4 subtype frequently detected in wild birds and poultry . Despite its prevalence, research on H4 subtype AIV has been scarce, with a focus predominantly on the H4N2 and H4N6 subtypes. The zoonotic potential of H4N1 has not been investigated to date. Methods In this study, we used gene sequencing in conjunction with bioinformatics methodologies to analyze wild-type H4N1 AIV strain and mutant strains emerging from serial passaging in cell culture . Furthermore, we assessed the zoonotic potential of H4N1 and the alterations caused by mutations via a series of phenotype assays, including evaluation of receptor binding affinity, immunofluorescence assays, analyses of growth kinetics across different animal cell cultures, and in vivo pathogenicity studies. Results Our research reveals that H4N1 AIV can bind to human receptors and exhibits an affinity for hum...