ETIDIOH - NEW

  Abstract H7 high-pathogenicity avian influenza (HPAI) virus outbreaks can cause high rates of morbidity and mortality in poultry flocks , leading to devastating impacts on poultry industries. In December 2024 , an HPAI virus was detected on a poultry farm in New Zealand , being the first time a case of HPAI was reported in the country. Whole-genome sequencing, subtyping, phylogenetic, and mutation analyses were performed to characterize the virus. Results indicated a novel high-pathogenicity H7N6 avian influenza virus arose through a reassortment event between endemic low-pathogenicity H4N6 and H7 viruses, followed by two mutations at the H7 gene cleavage site . Mutation analysis suggests the novel H7N6 virus exhibits increased risk of host specificity shift , but further work is required to fully understand the functional impacts of the detected mutational events. In this instance, a timely biosecurity response was effective in eliminating the virus and preventing its transmissi...

  Highlights --  We conducted surveillance for influenza A viruses at live bird markets in northern Vietnam. --  Six different subtypes of influenza A virus were found co-circulating in the markets. --  Notable genetic mutations were found across many genes. --  These markets have great potential to generate new pandemic influenza A virus strains. Abstract Objectives Live bird markets (LBMs) in Asia have often been the source of human infections with avian influenza virus (AIV). Methods From July 2021 to August 2023, we employed a One Health approach in conducting periodic surveillance for novel influenza A viruses in five LBMs in northern Vietnam. Specimens were studied with egg culture, molecular assays, Sanger sequencing, and next-generation sequencing. Results We studied a total of 688 human, avian, and bioaerosol specimens . Among these, 118 ( 17.2% ) were found to have molecular evidence of AIVs . Next-generation sequencing of 92 isolates revealed multiple...

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...