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Establishing #Methods to #Monitor #Influenza A #H5N1 Virus in Dairy #Cattle #Milk, #Massachusetts, #USA

Abstract Highly pathogenic avian influenza A(H5N1) virus has caused a multistate outbreak among US dairy cattle , spreading across 16 states and infecting hundreds of herds since its onset. We rapidly developed and optimized PCR-based detection assays and sequencing protocols to support H5N1 molecular surveillance . Using 214 retail milk samples from 20 states for methods development, we found that H5N1 virus concentrations by digital PCR strongly correlated with quantitative PCR cycle threshold values ; digital PCR exhibited greater sensitivity. Metagenomic sequencing after hybrid selection was best for higher concentration samples, whereas amplicon sequencing performed best for lower concentrations. By establishing these methods, we were able to support the creation of a statewide surveillance program to perform monthly testing of bulk milk samples from all dairy cattle farms in Massachusetts , USA, which remain negative to date. The methods, workflow, and recommendations described p...

A #coronavirus assembly #inhibitor that targets the viral #membrane protein

Abstract The coronavirus membrane protein (M) is the main organizer of coronavirus assembly. Here, we report on an M-targeting molecule , CIM-834, that blocks the assembly of SARS-CoV-2. CIM-834 was obtained through high-throughput phenotypic antiviral screening followed by medicinal-chemistry efforts and target elucidation. CIM-834 inhibits the replication of SARS-CoV-2 (including a broad panel of variants) and SARS-CoV. In SCID mice and Syrian hamsters intranasally infected with SARS-CoV-2, oral treatment reduced lung viral titres to nearly undetectable levels, even (as shown in mice) when treatment was delayed until 24 h before the end point. Treatment of infected hamsters prevented transmission to untreated sentinels. Transmission electron microscopy studies show that virion assembly is completely absent in cells treated with CIM-834. Single-particle cryo-electron microscopy reveals that CIM-834 binds and stabilizes the M protein in its short form, thereby preventing the conformati...

Detection of #antibodies against #influenza A viruses in #cattle

ABSTRACT Unexpected outbreaks caused by the H5N1 highly pathogenic avian influenza virus (HPAIV) in dairy cows in the United States (US) have raised significant veterinary and public health concerns . When and how the H5N1 HPAIV was introduced into dairy cows and the broader epidemiology of influenza A virus (IAV) infections in cattle in the US remain unclear. Herein, we performed a retrospective study to screen more than 1,700 cattle serum samples collected from different bovine breeds in the US from January 2023 to May 2024 using an enzyme-linked immunosorbent assay (ELISA) targeting the nucleoprotein (NP) to detect IAV infections, and the positive samples were further tested by hemagglutination inhibition (HI) assay . Results showed that 586 of 1,724 samples (33.99%) from 15 US states were seropositive by the NP ELISA assay , including 78 samples collected in 2024 and 508 samples collected in 2023 . Moreover, the HI assay revealed that 45 of these ELISA-positive samples were positiv...

#Transmission of #bovine #H5N1 virus in a #hamster #model

LETTER Transmission among mammals of bovine highly pathogenic avian influenza (HPAI) H5N1 viruses , which have caused outbreaks in US dairy cattle (1–3), has been demonstrated in ferrets by our group (4, 5) and the US Centers for Disease Control and Prevention (CDC) (6). These studies showed that these viruses can be transmitted among ferrets via respiratory droplets , albeit with lower efficiency than seasonal human influenza viruses. In contrast, bovine HPAI H5N1 viruses spread easily among ferrets through direct contact (3 of 3 [100%] ferrets) (6). Although ferrets are frequently used for influenza virus transmission (7–9) and vaccine efficacy (10, 11) studies, they demand considerable housing space and personnel and can be difficult to handle. Here, we investigated the transmissibility of the bovine HPAI H5N1 virus A/Texas/37/2024 (TX/37), which was 100% lethal in ferrets inoculated with as little as 10 plaque-forming units (PFUs) (5) by using a hamster model .  (...) Bovine HP...

Quantifying #viral #pandemic #potential from experimental #transmission #studies

Abstract In the past two decades, two pandemic respiratory viruses (H1N1 and SARS-CoV-2) have emerged via spillover from animal reservoirs . In an effort to avert future pandemics, surveillance studies aimed at identifying zoonotic viruses at high risk of spilling over into humans act to monitor the `viral chatter' at the animal-human interface . These studies are hampered, however, by the diversity of zoonotic viruses and the limited tools available to assess pandemic risk. Methods currently in use include the characterization of candidate viruses using in vitro laboratory assays and experimental transmission studies in animal models . However, transmission experiments yield relatively low-resolution outputs that are not immediately translatable to projections of viral dynamics at the level of a host population. To address this gap, we present an analytical framework to extend the use of measurements from experimental transmission studies to generate more quantitative risk assessm...

Promising effects of #duck #vaccination against highly pathogenic avian #influenza, #France 2023-24

Abstract The ongoing panzootic of highly pathogenic avian influenza (HPAI) H5 clade 2.3.4.4b has caused widespread poultry mortality and raised concerns about zoonotic pandemics and wildlife conservation . France recently adopted a preventive vaccination strategy , vaccinating domestic ducks with inactivated and mRNA vaccines . This study evaluates the impact of this campaign on reducing HPAI H5 outbreaks. Using predictive modeling based on previous outbreak data, the expected number of outbreaks in 2023-24 without vaccination was significantly higher than the observed cases, indicating a 95.9% reduction attributable to vaccination . These findings suggest that vaccination effectively mitigated the HPAI H5 outbreak in France. Source: BioRxIV,  https://www.biorxiv.org/content/10.1101/2024.08.28.609837v3 ____

Jamaican fruit #bats’ competence for #Ebola but not #Marburg virus is driven by intrinsic differences

Abstract Ebola virus (EBOV) and Marburg virus (MARV) are zoonotic filoviruses that cause hemorrhagic fever in humans . Correlative data implicate bats as natural EBOV hosts , but neither a full-length genome nor an EBOV isolate has been found in any bats sampled. Here, we model filovirus infection in the Jamaican fruit bat (JFB), Artibeus jamaicensis, by inoculation with either EBOV or MARV through a combination of oral, intranasal, and subcutaneous routes . Infection with EBOV results in systemic virus replication and oral shedding of infectious virus. MARV replication is transient and does not shed. In vitro, JFB cells replicate EBOV more efficiently than MARV, and MARV infection induces innate antiviral responses that EBOV efficiently suppresses. Experiments using VSV pseudoparticles or replicating VSV expressing the EBOV or MARV glycoprotein demonstrate an advantage for EBOV entry and replication early , respectively, in JFB cells. Overall, this study describes filovirus species-sp...

#UK, #England: Confirmed findings of #influenza of #avian origin in captive #mammals (as of March 25 '25)

Sheep, March 2025 One domestic sheep (Ovis aries) tested positive for influenza of avian origin (H5N1) in March 2025 . The case was identified following routine surveillance of farmed livestock on a premises in Yorkshire where highly pathogenic avian influenza (H5N1) had been confirmed in other captive birds . The single animal was a ewe with signs of mastitis but no other clinical signs . The milk was positive by polymerase chain reaction (PCR) and the blood tested positive for H5 antibodies.   All affected birds and the infected ewe were humanely culled to mitigate the risk of further disease spread. Further official testing of the remaining flock of sheep were all negative for the presence of avian influenza virus. Source: DEFRA,  https://www.gov.uk/government/publications/bird-flu-avian-influenza-findings-in-captive-mammals/confirmed-findings-of-influenza-of-avian-origin-in-captive-mammals ____

Murine #betacoronavirus #spike protein: A major #determinant of #neuropathogenic properties

Highlights The current review highlights the following major findings from the literature. 1.The genomic control of pathogenic properties of murine β-coronavirus. 2.Plausible mechanism of virus-induced neuroinflammatory demyelination and axonal loss. 3.Spike protein as a major determinant of MHV-induced neuropathogenesis. 4.The minimal essential motif in fusion peptide responsible for neuropathogenesis. 5.mCoV research sheds light on hCoV neuropathogenesis and helps design anti-virals. Abstract Coronaviruses have emerged as a significant challenge to human health . While earlier outbreaks of coronaviruses such as SARS-CoV and MERS-CoV posed serious threats , the recent SARS-CoV-2 pandemic has heightened interest in coronavirus research due to its pulmonary pathology , in addition to its neurological manifestations . In addition, the patients who have recovered from SARS-CoV-2 infection show long-term symptoms such as anosmia, brain fog and long COVID. A major hurdle in studying these v...

Still Life with Cheeses, Almonds and Pretzels (Clara Peeters, Date: 1615)

  Public Domain. Source: WikiArt,  https://www.wikiart.org/en/clara-peeters/still-life-with-cheeses-almonds-and-pretzels-1615 ____

Young #boy in #Cambodia contracts #H5N1 #birdflu

PHNOM PENH, March 23 (Xinhua) -- A three-year-and-six-month boy from northeast Cambodia's Kratie province has been confirmed for H5N1 human avian influenza , raising the number of cases to three so far this year , said a Ministry of Health's statement on Sunday. The boy had been brought to the hospital in a critical condition with fever, cough, and dyspnea , it said, adding that he is receiving medical treatment with the utmost care from a team of doctors. "According to queries, the patient's family raised chickens and about five chickens had died , as some others were sick, and his family members cooked the dead poultry for food," the statement said. Health authorities are looking into the source of the infection and are examining any suspected cases or people who have been in contact with the patient in order to prevent an outbreak in the community, it added. Among the three human cases of H5N1 so far this year , two had died, and all patients reportedly had a h...

#Coronavirus Disease Research #References (by AMEDEO, March 22 '25)

  Ann Intern Med Correction: Anticoagulation Among Patients Hospitalized for COVID-19. Ann Intern Med. 2025 Mar 18. doi: 10.7326/ANNALS-25-00916. PubMed          Antiviral Res SAFIRIYU AA, Hussain A, Dewangan N, Kasle G, et al The fusion peptide of the spike protein S2 domain may be a mimetic analog of beta-coronaviruses and serve as a novel virus-host membrane fusion inhibitor. Antiviral Res. 2025 Mar 16:106144. doi: 10.1016/j.antiviral.2025.106144. PubMed           Abstract available XU M, Zhang Z, Sun Y, Mai H, et al Corrigendum to "IgA class switching enhances neutralizing potency against SARS-CoV-2 by increased antibody hinge flexibility" [Antiv. Res. (2025) 106082]. Antiviral Res. 2025 Mar 20:106146. doi: 10.1016/j.antiviral.2025.106146. PubMed          Graefes Arch Clin Exp Ophthalmol ZUREIK A, Couturier A, Delcourt C Evolution of ophthalmological care in adult with ...

#Influenza and Other Respiratory Viruses Research #References (by AMEDEO, March 22 '25)

  Am J Med HOLLAND J, Sheehan D, Brown S, O'Flanagan S, et al Immune Response and Cognitive Impairment in Post-COVID Syndrome: A Systematic Review. Am J Med. 2025;138:698-711. PubMed           Abstract available PASCULLI P, Zingaropoli MA, Dominelli F, Solimini AG, et al Insights into Long COVID: Unraveling Risk Factors, Clinical Features, Radiological Findings, Functional Sequelae and Correlations: A Retrospective Cohort Study. Am J Med. 2024 Sep 17:S0002-9343(24)00569-2. doi: 10.1016/j.amjmed.2024. PubMed           Abstract available XU J, Wu D, Yang J, Zhao Y, et al Adult Outpatients with Long COVID Infected with SARS-CoV-2 Omicron Variant. Part 1: Oral Microbiota Alterations. Am J Med. 2025;138:732-741. PubMed           Abstract available YOO KH, Lee SH, Cho Y, Kim YJ, et al Synergistic Effect of SARS-CoV-2 Infection and COVID-19 Vaccination on the Risk of Ven...

Impact of #pH and #temperature in dairy #processing on the infectivity of #H5N1 avian #influenza viruses

Abstract Highly pathogenic avian influenza viruses (HPAIV) of subtype H5N1 (clade 2.3.4.4b) have crossed the species barrier and caused a mastitis-like infection in dairy cows . The high levels of infectious virus found in the milk raised considerable concerns about the safety of raw milk products . This study examined the effect of temperature and pH on the stability of HPAIV and low-pathogenic avian influenza viruses (LPAIV). We found that H5N1 HPAIV remained infectious in milk at 4 degrees Celsius for four weeks , with slow decreases at 21 degrees Celsius, and complete inactivation at 37 degrees Celsius after four weeks . H5N1 LPAIV was stable at 50 degrees Celsius for 30 minutes but inactivated at higher temperatures (55 degrees Celsius for 10 minutes, 60 degrees Celsius for 1 minute, or 72 degrees Celsius for 30 seconds). At pH levels between 6 and 10 , the virus remained stable but was partially inactivated at pH 5.0 and completely inactivated at pH 4.0. During yogurt production,...

Crucial role for #iron #metabolism in mediating #influenza A virus #infection and associated disease

Abstract Rationale and Objectives :  Iron availability and metabolism are important in the pathogenesis of bacterial infections . More recently, links have been reported between iron and the severity of viral infections . In this study, we characterize a crucial relationship between iron metabolism and IAV infection and disease.  Methods :  Iron-related gene expression was assessed in human airway epithelial cells (AEC) infected with IAV. AECs were cultured with ferric iron, iron-loaded transferrin, or iron chelator, deferoxamine (DFO), prior to infection with IAV. Mice were placed on a high iron diet for 8 weeks prior to infection with IAV or treated with anti-transferrin receptor-1 (TFR1) antibody during IAV infection. The effects of iron modulation and depletion of TFR1-mediated responses on IAV infection were assessed.  Measurements and main results :  Iron-related gene expression and metabolism are altered systemically and in lung tissues and AECs during IA...

#USA, Monitoring for Avian #Influenza #H5 Virus In #Wastewater {week 11-25}

{Excerpt} Time Period: March 09 - March 15, 2025 -- H5 Detection :  12 sites ( 2.7% ) -- No Detection :  431 sites ( 97.3% ) -- No samples in last week :  177 sites (...) Source: US Centers for Disease Control and Prevention,  https://www.cdc.gov/bird-flu/h5-monitoring/index.html ____