Skip to main content

Posts

Showing posts from June 16, 2025

#Assessment of public #health #risk of novel #reassortant #H3N3 avian #influenza viruses that emerged in #chickens

ABSTRACT Influenza A (H3N2) viruses are historically responsible for the 1968 Hong Kong flu pandemic. Since then, H3N2 has continued to circulate as a seasonal influenza virus in humans. Public health concerns were raised in 2022 when human infections with novel reassortant H3N8 influenza viruses originating from chickens were first reported in China . Here, we conducted a systematic surveillance of H3 avian influenza viruses (AIVs) circulating in poultry and assessed the public health risk of emergent H3 reassortants. We found that H3 AIVs were prevalent in both ducks and chickens . Notably, in December 2022, a novel chicken-derived H3N3 subtype virus was identified, which gradually replaced the previously predominant H3N8 virus and became prevalent in chickens. Genetic analysis demonstrated that the novel H3N3 virus is a triple-reassortment strain with the H3 gene segment from chicken H3N8 virus, the N3 gene segment from the H10N3 virus , and internal gene segments derived from H9N2 ...

Virological characterization of a new isolated strain of #Andes virus involved in recent person-to-person #transmission #outbreak reported in #Argentina

Abstract On November 2, 2018, a person-to-person transmission outbreak of Andes virus (Orthohantavirus andesense) began in the small town of Epuyén, Argentina . The strain demonstrated a high capacity for sustained transmission among the human population requiring the implementation of quarantine measures , rigorous contact tracing , isolation of close contacts, and active clinical monitoring to prevent further spread. In this study, we report the isolation of this strain, which we name the ARG-Epuyén strain , directly from a clinical sample after just three passages in cell culture. Complete sequencing revealed only a single amino acid change post-isolation , suggesting that this strain can be considered a non-adapted wild-type Andes virus , marking a critical step toward the development of medical countermeasures against this emerging pathogen. The pathogenicity and transmissibility potential of ARG-Epuyén were evaluated in hamsters , the only animal model for Hantavirus Pulmonary Sy...

#Persistence and Active #Replication Status of #Oropouche Virus in Different Body Sites: Longitudinal Analysis of a #Traveler Infected with a Strain Spreading in Latin America

Abstract An unprecedented outbreak of Oropouche virus (OROV) is occurring in the Americas, characterized by thousands of confirmed cases and a wide geographical spread, including areas outside the Amazon Basin. Little is known about this neglected arbovirus regarding its pathophysiological aspects and potentially different transmission modes . This study describes the clinical course of a man who returned from a trip to Cuba and presented to our hospital 4 days after the onset of febrile symptoms. The patient was diagnosed with Oropouche fever and was followed for 177 days after the onset of symptoms. We performed a longitudinal investigation of the samples collected from several body sites ( whole blood, serum, urine, and semen ) with the aim of providing further insights into OROV infection dynamics, using the detection of antigenomic RNA as a marker of active viral replication. Clinical samples that were longitudinally collected over the course of OROV infection showed consistently ...

The #Seroprevalence of #Influenza A Virus #Infections in Polish #Cats During a Feline #H5N1 Influenza #Outbreak in 2023

Abstract Recently, cats have emerged as potential incidental hosts for avian and human influenza A viruses (IAVs), including the highly pathogenic avian influenza (HPAI) H5N1 virus. Following an unprecedented outbreak of H5N1 HPAI in cats in Poland in June 2023, we conducted a cross-sectional epidemiological study to assess the seroprevalence of IAV, especially H5Nx , infections in domestic cats. Eight hundred thirty-five serum samples collected in June 2023 were tested using a competitive ELISA for antibodies to IAV nucleoprotein. Positive or doubtful samples were further screened for H5-specific antibodies. The overall seropositivity for IAV was 8.5% (CI 95%: 6.8%, 10.6%; 71/835 cats), and 23/68 IAV-seropositive cats (33.8%) were also seropositive for H5 antigen . Multivariable analysis identified young age (≤8 years) and male sex as significant risk factors for H5 seropositivity, while non-H5-IAV seropositivity was more common in cats aged ≥12 years. These findings suggest different...