ETIDIOH - NEW

  Abstract Viral diseases cause significant economic losses within the equine population. Horses are susceptible to equine coronavirus (ECoV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), although only ECoV has been associated to clinical disease . The aim of this study was to investigate, for the first time in Algeria , the seroprevalence of ECoV and SARS-CoV-2 antibodies and the prevalence of ECoV infection in horses . In 2022, a total of 299 serum samples was collected from horses aged 1 to 27 years . Serological analysis for the presence of ECoV and SARS-CoV-2 was performed using a validated in-house and a commercially available ELISA, respectively. In addition, fecal samples of these animals were tested for the presence of ECoV RNA by RT-qPCR . SARS-CoV-2-ELISA positive sera with high S/P ratios and negative samples close to the doubtful threshold were retested using a virus neutralization test ( VNT ). The seroprevalence of ECoV and SARS-CoV-2 in the teste...

  Int J Infect Dis TENG Z, Li L, Che T, Liang J, et al A Novel Balamuthia Lineage Causing Fatal Granulomatous Amoebic Encephalitis in an Immunocompetent Infant. Int J Infect Dis. 2025 Sep 17:108063. doi: 10.1016/j.ijid.2025.108063. PubMed           Abstract available J Med Virol PLICANTI E, Deiana A, Nottoli S, Lottini G, et al A Pyrido-Quinoxaline Derivative That Downregulates Reticulon 3 Protein Exhibits Potent Antiviral Activity Against Zika Virus. J Med Virol. 2025;97:e70605. PubMed           Abstract available J Virol TSUJINO S, Tsuda M, Nao N, Okumura K, et al Evolution of BA.2.86 to JN.1 reveals that functional changes in non-structural viral proteins are required for fitness of SARS-CoV-2. J Virol. 2025 Sep 23:e0090825. doi: 10.1128/jvi.00908. PubMed           Abstract available HAMMER E, Flynn C, Rossler J, Erder J, et al Prediction of COVID-19 disease pr...

  Am J Med WAHID L, Kwon T, Kreuziger LB, Kasthuri RS, et al Extended Thromboprophylaxis in Patients Hospitalized with COVID-19 at Time of Discharge is Not Associated with Improvement in Quality of Life. Am J Med. 2025;138:1464-1468. PubMed           Abstract available Biochem Biophys Res Commun ZHANG L, Li Y, Ye K, Wang P, et al Article I. metformin affects H1N1-induced apoptosis in lung epithelial cells by the miR-130a-5p-regulated PI3K/AKT signaling pathway. Biochem Biophys Res Commun. 2025;782:152526. PubMed           Abstract available J Gen Virol HA Y, Lee YH, Jo HS, Kwon TW, et al Susceptibility of different mouse strains to SARS-CoV-2 spike receptor-binding domain protein-induced lung inflammation: a comparative study. J Gen Virol. 2025;106. PubMed           Abstract available J Infect Dis GAILLET A, Layese R, Fourati S, Celante H, et al Clinical Phenotype...

  Abstract In China, low pathogenic avian influenza (LPAI) H3N8 virus is widespread among chickens and has recently caused three zoonotic infections , with the last one in 2023 being fatal . Here we evaluated the relative pandemic risk of this 2023 zoonotic H3N8 influenza virus, utilizing our previously published decision tree. Serological analysis indicated that a large proportion of the human population does not have any cross-neutralizing antibodies against this H3N8 strain. LPAI H3N8 displayed a dual affinity for a2-3 and a2-6 sialic acids and replicated efficiently in human bronchial epithelial cells . Furthermore, we observed H3N8 transmission via direct contact but not aerosols to ferrets with pre-existing H3N2 immunity. Although pre-existing H3N2 immunity resulted in a shortened disease course in ferrets, it did not reduce disease severity or replication in the respiratory tract. This study suggests that this zoonotic H3N8 strain has moderate pandemic potential and emphasiz...

  Abstract In 2024, a human infection with clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) virus was identified in the United States in an individual with no known exposure . Genetic analysis revealed two hemagglutinin (HA) substitutions, P136S and A156T, which may alter viral antigenicity . Virus isolation was unsuccessful, preventing timely serologic analysis. To overcome this limitation, we generated recombinant viruses by reverse genetics and characterized the effects of the substitutions on antigenicity, receptor binding , and replicative fitness. The A156T substitution introduced a potential N-linked glycosylation site , resulting in altered antigenicity and reduced replication in primary human nasal epithelial cells and ferrets . Importantly, the A(H5N1) candidate vaccine virus (CVV) IDCDC-RG80A, which possesses HA-T156, remained antigenically effective against viruses with and without these substitutions. These findings highlight the importance of sequencing, rever...

  Abstract In North-East Germany's offshore islands and mainland coast, wild ruminants, boar, and carnivores were tested for H5-HPAI antibodies . Wild ruminants were seronegative ; 3.5% of boar and 12.5-21.9% of carnivores were seropositive , evidencing frequent spillover . Because such events may accelerate mammalian - and ultimately human - adaptation , sustained One-Health monitoring is essential. Competing Interest Statement The authors have declared no competing interest. Funder Information Declared European Union, 101084171 "KAPPA-FLU" Helmholtz Institute for One Health, WiMoPOH Source: BioRxIV,  https://www.biorxiv.org/content/10.1101/2025.09.30.678011v1 ____

  Summary Background Post-acute sequelae of SARS-CoV-2 infection (PASC) remain a major public health challenge . Although previous studies have focused on characterising PASC in children and adolescents after an initial infection , the risks of PASC after reinfection with the omicron variant remain unclear. We aimed to assess the risk of PASC diagnosis (U09.9) and symptoms and conditions potentially related to PASC in children and adolescents after a SARS-CoV-2 reinfection during the omicron period. Methods This retrospective cohort study used data from 40 children's hospitals and health institutions in the USA participating in the Researching COVID to Enhance Recovery (RECOVER) Initiative. We included patients younger than 21 years at the time of cohort entry; with documented SARS-CoV-2 infection after Jan 1, 2022; and who had at least one health-care visit within 24 months to 7 days before the first infection. The second SARS-CoV-2 infection was confirmed by positive PCR, antigen...

  Abstract Since 2020, the outbreak of high pathogenicity avian influenza (HPAI) H5N1 virus clade 2.3.4.4b has turned into the largest documented panzootic 1,3. Here, we describe its arrival into the Indian Ocean sub-Antarctic archipelagos of Crozet and Kerguelen , where we first detected the virus in October 2024 in dead southern elephant seals . While the panzootic is ongoing, it has already caused unprecedented mortalities of marine mammals and seabirds . We collected brain swabs from seal and seabird carcasses and obtained 25 novel HPAI H5N1 2.3.4.4b sequences . Using phylogeographic analyses, we show that there have been independent introductions of the virus to Crozet and Kerguelen islands , most likely from the distant South Georgia islands in the Southern Atlantic , and not from the more nearby coasts of South Africa . Our results point to a year-long gap in genomic surveillance in the sub-Antarctic region. Locally, our analyses show that the virus is transmitted between di...

  Highlights •  Raw pet foods and raw milk are emerging sources of H5N1 in pets . •  Cats are more severely infected with H5N1 when compared to dogs. •  H5N1 persistence in mammals indicate adaptive variants with increased zoonotic potential. •  No reported pet-to-human transmission of H5N1 has been reported. •  FDA now requires RMBD makers who are covered under FSMA to assess HPAI risk. Abstract The increasing popularity of raw meat-based diets (RMBDs) and raw milk feeding in companion animals presents a growing concern for zoonotic disease transmission. Recent evidence has demonstrated that these products can serve as vehicles for highly pathogenic avian influenza (HPAI) H5N1 , an emergent viral threat with a host range from birds, dairy cattle , and pets to humans . Since the emergence of clade 2.3.4.4b in 2020 , HPAI H5N1 has caused widespread outbreaks in poultry, wild birds, and mammals , including dairy cattle and cats . Transmission to pets has been...

  Abstract The emergence of H5N1 highly pathogenic avian influenza virus (HPAIV) clade 2.3.4.4b in dairy cattle across multiple U.S. states in early 2024 marks a major shift in the virus’s host range and epidemiological profile . Traditionally limited to bird species , the ongoing detection of H5N1 in cattle , a mammalian host not previously considered vulnerable, raises urgent animal and human health concerns about zoonoses and mammalian adaptation . We assessed the feasibility of using commercially available pasteurized milk as a sentinel matrix for the molecular detection and genetic characterization of H5N1 HPAIV. Our aim was to determine whether retail milk could serve as a practical tool for virological monitoring and to evaluate the use of full-length genome segment amplification for extracting genomic sequence information from this highly processed matrix. Our results link HPAIV sequences in store-bought milk to the cattle outbreak and highlight both the potential and the l...

  Abstract In March 2024, a highly pathogenic avian influenza H5N1 (HPAI) clade 2.3.4.4b virus was identified in US dairy cows , with spillover to cats, poultry, and humans . Up to 30% of commercial pasteurized milk tested contained viral genome copies . The impact of residual viral remnants on host immunity is unknown. Orally ingested proteins can stimulate gut-associated lymphoid tissues , potentially inducing tolerance and altering responses to later infection. We found that milk pasteurization fully inactivated pandemic H1N1 and bovine H5N1 influenza viruses yet preserved hemagglutinin (HA) protein integrity. In mice , repeated oral exposure to inactivated virus did not alter mortality after H5N1 virus challenge. Preliminary data showed that naïve mice exposed to improperly pasteurized milk containing live H5N1 virus developed lethal infection , whereas prior H1N1 infection conferred protection . Mice with preexisting H1N1 immunity remained protected when challenged with bovine...

  Int J Infect Dis TENG Z, Li L, Che T, Liang J, et al A Novel Balamuthia Lineage Causing Fatal Granulomatous Amoebic Encephalitis in an Immunocompetent Infant. Int J Infect Dis. 2025 Sep 17:108063. doi: 10.1016/j.ijid.2025.108063. PubMed           Abstract available J Med Virol PLICANTI E, Deiana A, Nottoli S, Lottini G, et al A Pyrido-Quinoxaline Derivative That Downregulates Reticulon 3 Protein Exhibits Potent Antiviral Activity Against Zika Virus. J Med Virol. 2025;97:e70605. PubMed           Abstract available J Virol TSUJINO S, Tsuda M, Nao N, Okumura K, et al Evolution of BA.2.86 to JN.1 reveals that functional changes in non-structural viral proteins are required for fitness of SARS-CoV-2. J Virol. 2025 Sep 23:e0090825. doi: 10.1128/jvi.00908. PubMed           Abstract available HAMMER E, Flynn C, Rossler J, Erder J, et al Prediction of COVID-19 disease pr...

  Am J Med WAHID L, Kwon T, Kreuziger LB, Kasthuri RS, et al Extended Thromboprophylaxis in Patients Hospitalized with COVID-19 at Time of Discharge is Not Associated with Improvement in Quality of Life. Am J Med. 2025;138:1464-1468. PubMed           Abstract available Biochem Biophys Res Commun ZHANG L, Li Y, Ye K, Wang P, et al Article I. metformin affects H1N1-induced apoptosis in lung epithelial cells by the miR-130a-5p-regulated PI3K/AKT signaling pathway. Biochem Biophys Res Commun. 2025;782:152526. PubMed           Abstract available J Gen Virol HA Y, Lee YH, Jo HS, Kwon TW, et al Susceptibility of different mouse strains to SARS-CoV-2 spike receptor-binding domain protein-induced lung inflammation: a comparative study. J Gen Virol. 2025;106. PubMed           Abstract available J Infect Dis GAILLET A, Layese R, Fourati S, Celante H, et al Clinical Phenotype...

  {Excerpt} Highly pathogenic avian influenza caused by H5N1 viruses emerged in East Asia in the late 1990s and spread to Europe, Africa, and the Middle East , circulating in wild and domestic birds and occasionally spilling over into mammals and humans . These viruses are classified into genetic lineages called clades based on differences in the gene encoding hemagglutinin , a key surface protein involved in cell entry. In 2021, one such lineage, clade 2.3.4.4b , crossed from Europe to Canada . It spread rapidly, reaching the southern tip of South America in less than 2 years and causing massive mortality in seabirds and marine mammals , including South American sea lions (Otaria flavescens) and southern elephant seals (Mirounga leonina) (1). However, human mortality has been markedly lower in the present H5N1 outbreak than in past ones. If the virus evolves the capacity to transmit from human to human, understanding this reduction will be essential for mounting an effective respo...

  Abstract Influenza virus cross-subtype antibodies targeting the hemagglutinin (HA) head are rare . Here, we found that a large proportion of monoclonal antibodies (mAbs) isolated from individuals immunized with the 2021-22 seasonal influenza vaccine bound to an epitope on the HA head of both the H1N1 vaccine strain and H3N2 strains from the mid-1990s. These H1/H3 cross-reactive antibodies were also found in polyclonal sera , but only in samples from individuals born in the 1990s . Ferrets sequentially exposed to an H3N2 virus from the 1990s and a contemporary seasonal influenza vaccine produced the same type of H1/H3 cross-reactive antibodies. We found evidence that H1N1 viruses are currently evolving within the human population to abrogate the binding of these antibodies . Together, our study demonstrates how prior influenza virus exposures can influence the specificity of antibodies elicited by entirely different influenza virus subtypes, and how viruses evolve to escape these ...

  Summary -- What is already known about this topic? -  Influenza-associated encephalopathy (IAE) is a rare, severe neurologic complication of influenza. -- What is added by this report? - During the high-severity 2024–25 influenza season, 109 U.S. pediatric IAE cases were identified; 55% of affected children were previously healthy . Thirty-seven IAE cases were subcategorized as acute necrotizing encephalopathy (ANE), a severe form of IAE characterized by rapid neurologic decline and a poor prognosis . Overall, 74% of IAE patients were admitted to an intensive care unit , and 19% died ; 41% of ANE patients died. Only 16% of vaccine-eligible IAE patients had received the 2024–25 influenza vaccine. -- What are the implications for public health practice? - All children are at risk for severe neurologic complications of influenza . Annual influenza vaccination is recommended for all children aged ≥6 months to prevent influenza and associated complications, potentially including ...