ETIDIOH - NEW

  Abstract Influenza D virus (IDV), primarily found in livestock species, has demonstrated cross-species transmission potential , yet its threat to humans remains poorly understood . Here, we curated a panel of IDV isolates collected during field surveillance from 2011 to 2020 from swine and cattle to assess their ability to infect human airway cells as a proxy for zoonotic threat assessment. Using lung epithelial cell lines , primary well-differentiated airway epithelial cultures, and precision-cut lung slices , we demonstrated that IDV efficiently propagates in cells and tissues from the human respiratory tract , reaching titers comparable to human influenza A virus (IAV). Infection kinetics in primary porcine airway cultures and respiratory tissues mirrored those from human , suggesting similar infectivity across species. To define host responses to IDV infection, we evaluated innate immune sensing and downstream interferon signaling in human respiratory cells. IDV infection res...

  ABSTRACT The H1N1 influenza virus is a major pandemic and seasonal pathogen with a broad host range , posing a substantial threat to human health and underscoring the need for continuous surveillance . Wild birds , as natural reservoirs of avian influenza viruses (AIVs), carry H1N1 strains capable of reassorting with other influenza viruses, which can drive pandemic emergence. The global migration of wild birds facilitates the spread of these viruses, and their interactions with poultry increase the risk of cross-species transmission , further amplifying the public health threat. However, knowledge of H1N1 genetic diversity in wild birds remains limited. Database analysis shows 80% of avian-origin H1N1 isolates come from wild birds across over 40 countries , mainly in North America, Europe and Asia . This study characterized the molecular traits and genetic evolution of four H1N1 AIVs isolated from common teal and spot-billed ducks during 2019–2021 . Phylogenetic and sequence ana...

  Antiviral Res YURGELONIS I, Rai DK, Li Z, Washington B, et al Analysis of Ibuzatrelvir's Activity Against SARS-CoV-2 Circulating Variants and In Vitro Resistance Mutations. Antiviral Res. 2026 Jan 30:106352. doi: 10.1016/j.antiviral.2026.106352. PubMed           Abstract available BMJ LEI Z Reduced disease detection during covid-19. BMJ. 2026;392:s236. PubMed          Clin Infect Dis MA KC, Surie D, Dean N, Paden CR, et al Integrating genomic data into test-negative designs for estimating lineage-specific COVID-19 vaccine effectiveness. Clin Infect Dis. 2026 Feb 2:ciag059. doi: 10.1093. PubMed           Abstract available Int J Infect Dis MICHELI G, Mondi A, Roen A, Taramasso L, et al Did the COVID-19 pandemic shift the landscape of late HIV diagnosis? Int J Infect Dis. 2026 Jan 28:108437. doi: 10.1016/j.ijid.2026.108437. PubMed        ...

  Antimicrob Agents Chemother LLORENTE J, Sempere J, Llamosi M, Perez-Garcia C, et al Emergence of antibiotic-resistant pneumococcal serotypes causing invasive pneumococcal disease in children, Spain. Antimicrob Agents Chemother. 2025 Dec 31:e0153025. doi: 10.1128/aac.01530. PubMed           Abstract available J Infect Dis VILLAFUERTE D, Fall A, Akin E, Werner AP, et al Genomic Evolution of Influenza A Virus During the 2024-2025 Season, the Johns Hopkins Health System: Antigenic Drift Reduces Serum Neutralization. J Infect Dis. 2026 Feb 4:jiag069. doi: 10.1093. PubMed           Abstract available Pediatrics GAGO CM, Ruggiero CF, Gundewar A, Rose W, et al Parent Perspectives on the Interactive Role of Charitable and Federal Nutrition Assistance. Pediatrics. 2026 Jan 6:e2025072664. doi: 10.1542/peds.2025-072664. PubMed           Abstract available SALTHOUSE AL, Tann...

  Abstract Influenza (flu) is a common respiratory virus with seasonal global spread. Zoonotic viruses can occasionally cross species, leading to pandemic-level spread , and for flu viruses, this is considered an “antigenic shift ”. The flu can be particularly severe during pregnancy due to immune system adaptations that occur during pregnancy, with prior global pandemics causing excess hospitalizations, deaths, and other complications in the mothers and the neonates. We aim to review the current literature with respect to novel avian H5N1 and the potential impact of infection with flu during pregnancy. A systematic literature search was conducted. Here we provide a rapid summary of epidemiology and understanding of viral spread , published risks of H5N1 in pregnancy, the unique physiologic, cellular, and molecular adaptations making H5N1 infection unique in pregnancy, implementation of an effective vaccine program in event of a pandemic specific to pregnant individuals, optimizing...

  Abstract A case of H5N6 avian influenza was reported in Anhui Province, China . The viral titers in the patient's lungs and pharynx decreased rapidly after oseltamivir treatment , yet it still fatal . The whole genome sequencing suggested that it derived from four distinct sources and classified within the 2.3.4.4b clade . Source:  Link:  https://www.sciencedirect.com/science/article/pii/S1684118226000034?via%3Dihub ____

  Highlights •  74% pooled MERS-CoV seroprevalence in African dromedaries •  Highest MERS-CoV RNA incidence (15.3%) observed in juvenile dromedaries •  2.4% pooled MERS-CoV seroprevalence in camel -exposed humans •  African MERS-CoV clade C exhibits unique polymorphisms •  Clade-specific features might explain low MERS-CoV infection rates in Africa Abstract Objective We explored factors contributing to the low human MERS-CoV prevalence in Africa by assessing MERS-CoV epidemiological and genomic features. Methods We followed the PRISMA guidelines. We searched for articles on epidemiological and virological MERS-CoV characteristics in humans and camels in Africa until August 2025. We used a generalised linear mixed-effects model to calculate pooled proportions. We identified relevant polymorphisms in African MERS-CoV lineages compared with the prototypic EMC/2012 and contemporary Arabian MERS-CoV (clade B5). Results We included 53 articles, with 31 used in th...

  Abstract Middle East respiratory syndrome coronavirus (MERS-CoV) was identified as a human pathogen in 2012 and causes ongoing sporadic infections and outbreak clusters . Despite case fatality rates (CFRs) of over 30% and considerable pandemic potential , a safe and efficacious vaccine has not been developed. Here we report the design, characterization, and preclinical evaluation of MERS-CoV antigens . Our lead candidate comprises a stabilized spike displayed on a self-assembling ferritin nanoparticle that can be produced from a high-expressing, stable cell pool . This vaccine elicits robust MERS-CoV pseudovirus and authentic virus neutralizing antibody titers in BALB/c mice. Immunization of male non-human primates (NHPs) with one dose of Alhydrogel-adjuvanted vaccine elicited a > 103 geometric mean titer of pseudovirus neutralizing antibodies that was boosted with a second dose. Sera from these NHPs exhibited cross-reactivity against spike-pseudotyped lentiviruses from MERS-C...

  Abstract Of 19 human cases of avian influenza A(H5N1) virus infection detected during January 2023–March 2025 in Cambodia , 12 (63%) were detected directly by surveillance for severe acute respiratory infection (SARI) or indirectly by testing ill close contacts . SARI surveillance can supplement other surveillance sources for identifying H5N1 cases. Source:  Link:  https://wwwnc.cdc.gov/eid/article/32/3/25-0832_article ____

  ABSTRACT Oropouche virus (OROV), a neglected arbovirus, has historically been considered a self-limiting infection associated with febrile illness . However, the recent surge in cases since late 2023 has been marked by atypical outcomes , highlighting its underestimated clinical impact . Gastrointestinal symptoms such as diarrhea have also been reported, but the prevalence and mechanistic insight remain largely elusive. Here, through a meta-analysis of 12 identified clinical studies , we revealed a pooled prevalence of diarrhea as 15% (95% CI, 10%–20%) among the Oropouche patient population. In primary human intestinal organoid-based experimental models , we demonstrated productive infection by both a recent patient isolate (OROV-2024) and a historical strain (Be An19991). This is shown by the accumulation of intracellular OROV RNA, release of infectious particles, and immunostaining of OROV glycoprotein Gc. Interestingly, OROV infection mildly triggered the expression of type II...

  Abstract Introduction Seasonal influenza causes significant global morbidity, mortality, and economic burden . Ongoing viral evolution can lead to vaccine mismatch and the emergence of antiviral resistance , highlighting the importance of genomic surveillance. The 2024–2025 influenza season was characterized by high incidence and increased hospitalizations. Methods We analyzed influenza A virus (IAV) genomes and clinical characteristics from the 2024–2025 season . Whole-genome sequencing was performed on 648 influenza A–positive clinical specimens collected between October 2024 and April 2025. Results Hemagglutinin (HA) sequences were recovered from 74.23% (481/648) of samples and used for subtyping and phylogenetic analysis. A(H1N1)pdm09 and A(H3N2) viruses co-circulated , representing 55.5% and 44.5% of cases, respectively. Among A(H1N1)pdm09 viruses, the HA1 substitution T120A , located near the Sa antigenic site , increased more than twofold compared with the prior season. Ci...

  Abstract Background Household transmission of SARS-CoV-2 remains a key driver of community spread , with secondary attack rates in Thai households reaching approximately 50 %. There is limited evidence supporting the efficacy of antiviral post-exposure prophylaxis (PEP) in this context. Methods The phase 2/3, open-label, (1:1) cluster-randomized controlled trial in Thailand , 168 household close contacts from 76 index cases were enrolled to receive either favipiravir-PEP (FPV-PEP) (1600–2000 mg/day for 7 days) or usual care. The efficacy of FPV-PEP was investigated in preventing SARS-CoV-2 infection after contact with index cases. Results The incidence of confirmed SARS-CoV-2 infection was lower in the FPV-PEP group than in the usual care group (7.32 % vs. 14.47 %), although the difference was not statistically significant . A trend toward fewer early positive rapid diagnostic test results on day 3 was observed in the FPV-PEP group. Symptom development was less frequent among FPV...

  Abstract Highly pathogenic avian influenza H5N1 virus has spread to over 1,080 dairy farms across 18 states in the United States, resulting in 41 human infections and posing serious risks to both animal and public health . To address these risks, a hemagglutinin-based mRNA–lipid nanoparticle vaccine was developed , and its safety, immunogenicity, and protective efficacy in high-yielding lactating dairy cows were evaluated. The vaccine was well tolerated, had no adverse effects on health or milk production , and induced strong antibody responses . Two weeks after the second immunization, all the immunized cattle were fully protected against a high-dose H5N1 virus challenge . Notably, two-thirds of the cattle were still completely protected even at the 19th week after the first vaccination , when their serum antibody levels were very low. These data demonstrate that the mRNA vaccine confers robust, lasting protection against H5N1 virus in lactating dairy cows, providing a foundatio...

  {Summary} Recent headlines about influenza have reported a “super flu” causing a “record-breaking season” that is “overwhelming hospitals.” Although less dramatic, data from the Centers for Disease Control and Prevention (CDC) reveal substantial influenza activity : the agency estimated that there were more than 20 million cases of influenza illness, 270,000 influenza-related hospitalizations , and 11,000 deaths from influenza in the United States through January 24, 2026. These numbers aren’t extraordinary as compared with those from previous seasons, but some indicators of influenza activity and severity have been remarkable. (...) Source:  Link:  https://www.nejm.org/doi/full/10.1056/NEJMp2600395?query=TOC ____

  Abstract Middle East respiratory syndrome coronavirus (MERS-CoV) is an emerging coronavirus that can cause zoonotic disease in humans with lethal severe viral pneumonia . Dromedary camels are the source of zoonotic infection. As of November 2025, MERS-CoV has resulted in a total of 2630 reported cases, 37% of these being fatal . The number of reported human cases has been on a decreasing trend since 2016 and reached a nadir during the COVID-19 pandemic . The reason for the reduction of cases is unclear and may be multifactorial. We hypothesized that mutations accumulating in the virus spike protein may have reduced zoonotic potential . Here, we investigate the impact of recently emerged virus spike-protein mutations on virus replication competence using pseudoviruses and replication-competent recombinant viruses. We found that virus spike variants detected in 2019 and some from 2023 show a reduced cell entry, lower viral replication and reduced fitness in human primary alveolar e...

  Abstract Recent A(H5N1) zoonotic cases linked to poultry and cattle in North America highlight the urgent need to assess the pandemic potential of emerging strains . Using male ferrets , we evaluate two B3.13 and two D1.1 genotype A(H5N1) viruses isolated from humans and observe fatal disease and varying capacities for direct contact transmission . To enhance pandemic risk assessment , we conduct aerosol sampling using cyclone BC251 and water condensation capture-based SPOT samplers and perform comparative analyses to include additional A(H5N1), A(H9N2), A(H7N9), and A(H1N1)pdm09 strains with known transmissibility profiles. Although none of the A(H5N1) strains transmit via the air, B3.13 viruses are detected at significantly higher levels compared to D1.1 strains . Here we show strong correlations between viral loads in nasal washes, airborne virus shedding, and transmissibility in ferrets , highlighting the value of these metrics for identifying zoonotic influenza viruses that ...

  Abstract Decelerating gains in life expectancy (e0) in high-income countries have raised concerns about the future of human longevity . To enhance our understanding of these developments, we examine subnational (N = 450) mortality trends in Western Europe in the period 1992-2019. Between 1992 and 2005, gains in life expectancy were both substantial and widespread. Laggard regions experienced the fastest improvements, yielding rapid regional convergence. Between 2005 and 2019, however, gains in these regions decelerated , while remaining remarkably stable in vanguard regions, suggesting that it remains possible to continue extending longevity . The observed slowing of e0 gains is strongly associated with mortality at ages 55-74 , which increased in this period across large areas of Western Europe , particularly in Germany and France . In this work, we show that monitoring mortality trends at a fine geographical level is crucial for revealing both the potential for, and challenges ...

  Highlights •  IN-delivered ChAd-Texas vaccine elicits mucosal antibody and T cell responses •  IN-delivered ChAd-Texas vaccine protects against H5N1 in mice and hamsters •  IN delivery of ChAd-Texas vaccine confers greater protection than IM delivery •  ChAd-Texas induces H5N1 immunity in the setting of prior influenza immunity Summary The emergence of highly pathogenic avian H5N1 influenza viruses in dairy cows and humans has increased the potential for another pandemic . To address this risk, we developed chimpanzee adenoviral (ChAd)-vectored H5 hemagglutinin-targeted vaccines and tested their immunogenicity and efficacy in rodents . Immunization with ChAd-Texas (clade 2.3.4.4b) vaccine in mice elicits neutralizing antibody responses and confers protection against viral infection and mortality upon challenge with a human H5N1 isolate (A/Michigan/90/2024, clade 2.3.4.4b). Intranasal delivery of the ChAd-Texas vaccine elicits mucosal antibody and T cell respon...

Abstract Key to the success of influenza A virus as a pathogen are its numerous tactics of immune evasion. To suppress anti-viral cellular and organismal responses , influenza A virus encodes several immunomodulatory proteins , including the endoribonuclease PA-X . PA-X decreases inflammation and immune responses in in vivo infections by limiting host gene expression . PA-X is conserved in 99% of all influenza A viral strains , pointing to its importance as a crucial immunomodulator . However, it is not yet known how PA-X activity alters the antiviral response in the human airway or how it benefits the virus. To define how influenza A virus uses this protein to evade immune responses , we characterized the impacts of PA-X on the host response to infection in the infected and bystander cells of the airway epithelium using a 3D ex vivo model. We discovered that PA-X exerts a dual action on immune responses , dampening aspects of both the innate and adaptive immune systems . Consistent wi...

  Clin Infect Dis BRAMANTE CT, Boulware DR Preventing Long COVID With Metformin. Clin Infect Dis. 2026 Jan 29:ciaf700. doi: 10.1093. PubMed          Emerg Infect Dis PERERA RAPM, Marques A, Graham-Wooten J, Tan LH, et al Enhanced Isolation and Detection of COVID-19 in Hospitalized Patients Undergoing Antiviral Therapy. Emerg Infect Dis. 2026;32:103-113. PubMed           Abstract available Graefes Arch Clin Exp Ophthalmol NEO YN, Martinez-Alvarez L, Davagnanam I, Girafa G, et al Correction: Treatment of post-vaccination optic neuritis: implications from the global SARS-CoV-2 vaccination effort. Graefes Arch Clin Exp Ophthalmol. 2026 Jan 29. doi: 10.1007/s00417-026-07129. PubMed          Int J Infect Dis NGIAM JN, Wee LE, Lim JT, Loy EX, et al Early administration of neutralising monoclonal antibodies and post-acute sequelae of COVID-19. Int J Infect Dis. 2026 Jan 25:108435. ...