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Showing posts from June 4, 2025

The #hemagglutinin proteins of clades 1 and 2.3.4.4b #H5N1 #HPAI viruses exhibit comparable attachment patterns to #avian and #mammalian tissues

Abstract The global spread of the A/goose/Guangdong/1/96-lineage H5N1 highly pathogenic avian influenza (HPAI) viruses is accompanied by an expanded host range and the establishment of sustained viral transmission among dairy cattle . To evaluate if the evolving H5N1 viruses have changed tissue tropism over time, we compared the binding patterns of recombinant hemagglutinin (HA) proteins derived from clade 1 (A/Vietnam/1203/04, H5VN) and circulating clade 2.3.4.4b viruses detected from a wild bird (A/Eurasian Teal/Hong Kong/AFCD-HKU-23-14009-01020/2023, H5HK) and dairy cattle (A/bovine/Ohio/B24OSU-439/2024, H5OH). The HA protein of A(H1N1)pdm09 virus was included for comparison. Using bio-layer interferometry, H1 protein preferentially bound to the 2,6-linked sialoside 6'SLNLN while H5 proteins preferentially bound to the 2,3-linked sialoside 3'SLN. H5OH showed higher binding affinity to 3'SLN than H5HK and H5VN. The attachment pattern of H1 and H5 proteins to the respirato...

#SARS-CoV-2 infection #enhancement by #amphotericin B: implications for disease management

ABSTRACT Severe coronavirus disease 2019 (COVID-19) patients who require hospitalization are at high risk of invasive pulmonary mucormycosis . Amphotericin B (AmB), which is the first-line therapy for invasive pulmonary mucormycosis, has been shown to promote or inhibit replication of a spectrum of viruses. In this study, we first predicted that AmB and nystatin had strong interactions with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) proteins using in silico screening, indicative of drugs with potential therapeutic activity against this virus. Subsequently, we investigated the impact of AmB, nystatin, natamycin, fluconazole, and caspofungin on SARS-CoV-2 infection and replication in vitro. Results showed that AmB and nystatin actually increased SARS-CoV-2 replication in Vero E6, Calu-3, and Huh7 cells . At optimal concentrations, AmB and nystatin increase SARS-CoV-2 replication by up to 100- and 10-fold in Vero E6 and Calu-3 cells, respectively. The other antifungals t...

Quantifying the #zoonotic #risk profile of European #influenza A viruses in #swine from 2010 to 2020 inclusive

ABSTRACT H1 and H3 influenza A viruses (IAVs) circulating in European pigs are markedly distinct from those circulating in other global swine populations . These viruses exhibit significant genetic diversity , further expanded by periodic interspecies transmission of IAVs from humans into pigs , followed by sustained circulation. Several zoonotic IAV infections in humans in Europe have been associated with the 1C lineage of H1 IAVs . Given the predominance of H1 detections in pigs and their zoonotic potential, we quantified antigenic evolution of H1 viruses in European pigs using ferret and pig models and assessed diversity relative to swine IAV vaccine strains. Ferret and swine antisera comparisons revealed no significant differences in antibody responses . Viruses of the 1A.3.3.2 clade exhibited reduced cross-reactivity to human seasonal vaccine strains from 2009. Viruses of the 1B.1.2.2 clade showed no cross-reactivity to the 1978 human seasonal influenza viruses nor to candidate va...

A replicating recombinant vesicular stomatitis virus #model for dairy #cattle #H5N1 #influenza virus #glycoprotein #evolution

ABSTRACT A panzootic of highly pathogenic avian influenza (HPAI) H5N1 viruses from clade 2.3.4.4b has triggered a multistate outbreak in US dairy cattle and an unknown number of human infections . HPAI viruses are handled in specialized biocontainment facilities. Ethical considerations limit certain evolution experiments aimed at assessing viral resistance to potential therapeutics. We have developed a replicating recombinant vesicular stomatitis virus (rVSV) where we replaced its glycoprotein with the hemagglutinin (HA) and neuraminidase (NA) genes of a 2.3.4.4b H5N1 virus (rVSV-H5N1dc2024), which enables these experiments to be performed under standard biosafety considerations. This virus grows to high titers and encodes a fluorescent reporter to track infection. We demonstrate the utility of rVSV-H5N1dc2024 in neutralization experiments, the evaluation of antibody escape, and the characterization of resistance mutations to NA inhibitors. rVSV-H5N1dc2024 or similar viruses may accele...

#Phage-induced #protection against lethal #bacterial #reinfection

Significance In 2021, antimicrobial-resistant bacteria were responsible for 1.14 million deaths and associated with 4.71 million deaths globally. Patients who experience sepsis often face a higher risk of reinfections and hospital readmissions . To combat this crisis, bacteriophages —viruses that infect and kill bacteria—are regaining interest as a potential solution. Here, we show that mice infected with extraintestinal pathogenic Escherichia coli and treated with phage HP3 not only recover from the initial infection but also gain protection against a secondary challenge with the same bacterial strain. The protective effect is dependent on the bacteriolytic action of the phage. These findings shift phages from being solely therapeutic antimicrobials to dual-action immunotherapeutics capable of both clearing and preventing bacterial infections. Abstract Bacteriophages, or phages, are viruses that target and infect bacteria. Due to a worldwide rise in antimicrobial resistance (AMR), pha...

#Neuroinvasive #Oropouche virus in a patient with #HIV from extra-Amazonian #Brazil

{Excerpt} A novel reassortant Oropouche virus (OROV) lineage (with medium [M], large [L], and small [S] RNA segments : M1L2S2) has driven Brazil's largest and most geographically widespread OROV epidemic , expanding beyond the endemic Amazon basin to establish local transmission across multiple Brazilian states and other previously unaffected Latin American countries . The rapid spread of this lineage underscores its evolutionary potential and reinforces its significance as a public health threat .1 Similar to chikungunya and Zika viruses, expanding arboviruses can exhibit unexpected clinical and epidemiological shifts , including vertical transmissions , neuroinvasive effects, and potentially fatal outcomes.2–4 Although OROV typically causes self-limited febrile illness, accumulating clinical and experimental evidence suggests neurotropic potential .5 This Correspondence describes the first confirmed case of neuroinvasive OROV infection caused by the emergent M1L2S2 lineage in ext...

Persistence of #SARS-CoV-2 #Alpha #Variant in White-Tailed #Deer, #Ohio, USA

Abstract Free-ranging white-tailed deer (WTD) are highly susceptible to the SARS-CoV-2 virus . Through an opportunistic sampling of WTD in northeast Ohio, USA , during January–March 2023 , we identified 6 SARS-CoV-2 lineages from 36 sequences using the pangolin lineages tool, including the B.1.1.7 lineage (Alpha variant) and BQ.1.1, BQ.1.1.63, BQ.1.1.67, BQ.1.23, and XBB.1.5.35 lineages ( Omicron variant ). The Alpha variant, introduced by a single human-to-deer transmission event , was detected in 5 WTD in January 2023, more than 1 year after the most recent detection of the Alpha variant in humans in Ohio (August 2021). A genetically similar B.1.1.7 lineage virus from WTD in a nearby county in Pennsylvania was positioned with our Ohio deer transmission cluster, suggesting deer-to-deer transmission . The persistence of the Alpha variant in WTD in Ohio warrants continued surveillance to monitor if WTD can become a reservoir for displaced SARS-CoV-2 variants. Source: US Centers for Dise...

#Risk #evaluation of newly emerging #flu viruses based on genomic #sequences and AI

Abstract The recent resurgence of highly pathogenic avian influenza H5N1 viruses in North America and Europe has heightened global concerns regarding potential influenza pandemics. Despite significant progress in the surveillance and prevention of emerging influenza viruses, effective tools for rapid and accurate risk assessment remain limited. Here, we present FluRisk , an innovative computational framework that integrates viral genomic data with artificial intelligence (AI) to enable rapid and comprehensive risk evaluation of emerging influenza strains. FluRisk incorporates a curated database of over 1,000 experimentally validated molecular markers linked to key viral phenotypes , including mammalian adaptation, mammalian virulence, mammalian transmission, human receptor-binding preference , and antiviral drug resistance . Leveraging these markers, we developed three state-of-the-art machine learning models to predict human adaptation, mammalian virulence, and human receptor-binding ...