ETIDIOH - NEW

  ABSTRACT Swine influenza A virus (swIAV) is an important zoonotic pathogen with the potential to cause human influenza pandemics . Swine are considered “ mixing vessels ” for generating novel reassortant influenza A viruses . In 2009, a swine-origin reassortant virus (2009 pandemic H1N1, pdm/09 H1N1 ) spilled over to humans , causing a global influenza pandemic . This virus soon spread back into swine herds and reassorted with the circulating swIAVs. We previously reported that the genotype 4 (G4) reassortant Eurasian avian-like (EA) H1N1 virus , which bore pdm/09- and triple reassortant (TR)-derived internal genes, had been predominant in swine populations of China since 2016, posing a threat to both the swine industry and public health . Here, our ongoing surveillance confirmed that G4 EA H1N1 viruses remained the predominant swIAVs in China from 2019 to 2023 and had reassorted with the co-circulating swIAVs, such as the H3N2 virus, to generate novel reassortant EA H1N2 viruses...

  ABSTRACT The ferret model is widely used to study influenza A viruses (IAVs) isolated from multiple avian and mammalian species , as IAVs typically replicate in the respiratory tract of ferrets without the need for prior host adaptation . During standard IAV risk assessments , tissues are routinely collected from ferrets at a fixed time point post-inoculation to assess the capacity for systemic spread. Here, we describe a data set of virus titers in tissues collected from both respiratory tract and extrapulmonary sites 3 days post-inoculation from over 300 ferrets inoculated with more than 100 unique IAVs (inclusive of H1, H2, H3, H5, H7 , and H9 IAV subtypes, both mammalian and zoonotic origin ). All experiments were conducted by a single research group under a uniform experimental protocol , making it the largest well-controlled publicly available data set to date of discrete tissue titers reported on a per-ferret level. Analysis of these tissues revealed spatial variation in i...

  Highlights •  The H5N1 influenza virus-like particle vaccines are prepared through baculovirus expression vector system. • In vitro assessments have confirmed that this VLP vaccine has the correct conformation and functional activity. • This VLP vaccine induces robust humoral and cellular immune responses in mice , and provides complete protection against infection with the matched strain. Abstract Avian influenza virus infections pose a potential pandemic threat . The currently licensed vaccines have inherent limitations, emphasizing the urgent need for improved influenza vaccines. Here, we developed a novel hemagglutinin (HA) virus-like particle (VLP) vaccine candidate through the baculovirus expression vector system (BEVS). The engineered VLPs incorporate HA from H5N1 and matrix 1 (M1) protein from H1N1 . Comprehensive characterization revealed that purified HA VLPs exhibited morphological fidelity to native influenza virions while maintaining key viral biological propert...

  Abstract Highly pathogenic avian influenza virus of the H5N1 subtype has been infecting U.S dairy cattle and spreading among dairy farms since March 2024 . H5N1 surveillance systems for dairy farms are needed, but information on whether environmental sampling can inform these systems is lacking. To guide a surveillance framework , we determined the environmental locations on H5N1-affected dairies (n = 25) in four states (California, Colorado, Michigan, and Ohio) that harbored influenza A virus (IAV), and explored sample characteristics that may influence viral detection. A total of 623 samples from environments and sale barns were characterized for IAV and classified into six categories based on location. A total of 94 samples ( 15.1% ) had IAV detected , the majority in the following categories: milking equipment/personal protective equipment , parlor surfaces , and wastewater/lagoons/manure . These results suggest that dairy environments most likely to harbor IAV are those with...