ETIDIOH - NEW

  ABSTRACT Current U.S. surveillance for highly pathogenic avian influenza A(H5N1) in humans prioritizes individuals with known animal exposures , potentially missing community-acquired infections . To address this gap, we implemented universal H5 subtyping of all influenza A-positive respiratory samples collected within our hospital system , regardless of patient exposure history. Between August 2024 and April 2025, we subtyped 4,488 influenza A-positive samples and identified two cases positive for H5 RNA in Alameda County, California, USA . The first case was a 14-month-old girl with mild respiratory symptoms and no H5N1 exposure risks ; sequencing of the sample revealed an H5 gene closely related to clade 2.3.4.4b, genotype B3.13 viruses circulating in U.S. dairies . The second case was a 79-year-old male, also with no known exposures , whose sample reproducibly tested positive with a high cycle threshold value but could not be confirmed by public health laboratories. Both pati...

  Abstract Selection of advantageous mutations drives the emergence of dominant variants during seasonal influenza epidemics . However, within-host detection of such variants remains rare , limiting our understanding of how selection operates at the scale of individual hosts. In this study, we used a controlled human infection model to examine the within-host evolutionary dynamics in thirteen participants intranasally infected with a seasonal H3N2 influenza A virus . Although this clinical trial is ongoing , our work represents a pre-planned, interim, exploratory analysis. Results in this system were contrasted with those observed in a ferret model of infection. The inoculum, used in both humans and ferrets, carried standing diversity that enabled evaluation of variant trajectories during infection. Although the dynamics were variable among participants, in humans , the minor variants in the PA and NP gene segments tended to increase in frequency as infection progressed. Variant dy...

  Poultry farms in Podlaskie Region. Source:  Link:  https://wahis.woah.org/#/in-review/7177 ____

  Summary Background Lassa virus (LASV) is a persistent threat to public health in west Africa and beyond . LASV is endemic in west Africa and each year it is responsible for an estimated 2·7 million infections, 23 700 hospitalisations, and 5000 deaths . With over 32 reported cases of Lassa fever imported into non-endemic countries—one-third of which were fatal—the importance of enhanced detection and management of Lassa fever extends beyond west Africa. Methods The prevalence, pathogenesis, and persistence (PREPARE) study was a prospective cohort study among patients admitted to two hospitals in a hyperendemic area of Liberia . Any patients aged 5 years or older with a febrile illness were eligible to enrol and be tested for Lassa fever. The study aimed to measure the prevalence of LASV infection and assess the signs and symptoms, LASV viral replication kinetics, and LASV-specific IgM and IgG responses longitudinally among adults and children with laboratory-confirmed Lassa fever....

  Abstract Highly pathogenic H5N1 avian influenza viruses of clade 2.3.4.4b cause sporadic human infections and currently raise concerns about a new influenza pandemic . Heterogeneities in disease severity have been observed in the past and are reported among infected farm workers in the United States . These may be attributed to differences in pre-existing H5N1 cross-reactive antibodies . In this study, we characterize H5N1 cross-reactive antibody landscapes in the current population (#NCT05794412 and #NCT01022905) and assess the effect of AS03-adjuvanted pandemic H1N1 and non-adjuvanted seasonal influenza vaccination on H5N1 cross-neutralizing and IgG antibody titers targeting a range of influenza virus-derived antigens. We detect H5N1 cross-neutralizing antibodies using a vesicular stomatitis virus-based pseudovirus system that correlate well with antibodies inhibiting the spread of authentic H5N1 viruses, anti-group 1 hemagglutinin stalk and anti-trimeric hemagglutinin antibodi...

  Abstract Since its emergence in 2012, Middle East respiratory syndrome coronavirus (MERS-CoV) has posed a significant threat to human health . Recently, novel MERS-like coronaviruses with the potential for cross-species transmission have been identified. In this study, we focused on two newly isolated bat strains with putative health concern: BatCoV/Ii/GD/2014-422 (2014-422) and BtTp-BetaCoV/GX2012 (GX2012). We determined the cryo-EM structures of the spike glycoprotein trimer in the closed state for these two viruses. These structures display a more compact conformation compared to MERS-CoV spike . Biochemical characterization demonstrates that the spike receptor-binding domains (RBDs) of 2014-422 and GX2012 can bind to human dipeptidyl peptidase 4 (hDPP4). To investigate the structural determinants of pseudovirus infection, we solved the cryo-EM structures of 2014-422 RBD-hDPP4 and GX2012 RBD-hDPP4 complexes. The binding mode of the complex is conserved, but the angle of the RB...

  Boston — The Massachusetts Department of Public Health (DPH) is reporting very high and rising levels of influenza activity statewide as the Commonwealth moves through peak flu season .  Thousands of residents have become ill , forcing them to miss work, school, and other activities.  Many are experiencing serious complications , leading to increased visits to urgent care centers and emergency departments, and high levels of hospitalization .  The current widespread burden of illness underscores the importance of taking preventive measures , especially vaccination , to reduce severe disease and protect individuals, families, and communities. Tragically, influenza has already been reported to be associated with the deaths of three pediatric patients in Massachusetts during recent weeks.  In addition, there have been 29 adult influenza deaths reported so far this season.  While COVID-19 and respiratory syncytial virus (RSV) rates currently remain low, cases...