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Exploring Avian #Influenza Viruses in #Yakutia—The Largest #Breeding #Habitat of Wild Migratory #Birds in Northeastern #Siberia

Abstract Yakutia, the largest breeding ground for wild migratory birds in Northeastern Siberia , plays a big role in the global ecology of avian influenza viruses (AIVs). In this study, we present the results of virological surveillance conducted between 2018 and 2023, analyzing 1970 cloacal swab samples collected from 56 bird species . We identified 74 AIVs of H3N6, H3N8, H4N6, H5N3, H7N7, H10N3, and H11N9 subtypes in Anseriformes order. Phylogenetic analysis showed that the isolates belong to the Eurasian lineage and have genetic similarities with strains from East Asia, Europe, and North America. Cluster analysis has demonstrated the circulation of stable AIV genotypes for several years. We assume that Yakutia is an important territory for viral exchange on the migratory routes of migrating birds. In addition, several amino acid substitutions have been found to be associated with increased virulence and adaptation to mammalian hosts , highlighting the potential risk of interspecific...

#Sudan virus disease - #Uganda (#WHO D.O.N., April 26 '25)

{Summary} Situation at a glance On 26 April 2025, the Ministry of Health (MoH) of Uganda declared the end of the Sudan virus disease (SVD) outbreak after two consecutive incubation periods (a total of 42 days) since the last person confirmed with SVD tested negative for the virus on 14 March 2025.  A total of 14 SVD cases (including 12 confirmed cases and two probable cases) including four deaths (two confirmed and two probable) have been reported during this outbreak.  WHO and partners provided technical , operational and financial support to the government to contain the outbreak.  Although the outbreak has been declared over , health authorities are maintaining surveillance to rapidly identify and respond to any re-emergence.  Risk communication and community engagement will also continue to ensure the community stay informed and stigma to those who were affected is minimized. (...) Source: World Health Organization,  https://www.who.int/emergencies/disease-o...

#Influenza virus #infection in the #lungs leads to #pancytopenia and defective immune cell differentiation program in the #thymus and bone marrow

Abstract Exaggerated inflammation and cytokine storm are hallmark features of influenza A virus (IAV)-induced respiratory diseases. While previous studies unequivocally demonstrated the pathophysiological consequences (multiorgan failure) of IAV-associated cytokine storm, it remains unknown if IAV-induced systemic inflammation impacts the fitness and differentiation of immune cells from hematopoietic stem cells (HSCs). Our data on lethal IAV-infected C57BL/6 wildtype mice after 10 days of infection indicated reduced monocyte- and lymphocyte- counts in the peripheral blood, and overall cellularity of spleen, thymus and lymph nodes . IAV- infection resulted in increased numbers of myeloid cells, CD8+ T cells, alveolar macrophages (AVMs), CD11b+ dendritic cells (DCs) & plasmacytoid DCs (pDCs), whereas decreased frequencies of CD103+ DCs, in the lungs of IAV-infected mice. Analysis of spleen and draining lymph nodes indicated reduced absolute numbers of B cells, T cells, monocytes and ...

#Coronavirus Disease Research #References (by AMEDEO, April 26 '25)

  Am J Obstet Gynecol THEL H, Latour CD, Tsevat D, Dissanayake M, et al Prevalence of male and female permanent contraception and long-acting reversible contraceptives among commercially insured US population, 2010-2022. Am J Obstet Gynecol. 2025 Apr 18:S0002-9378(25)00230. PubMed          KEULS RA, Ochsner SA, O'Neill MB, O'Day DR, et al Single-nucleus transcriptional profiling of the placenta reveals the syncytiotrophoblast stress response to COVID-19. Am J Obstet Gynecol. 2025;232. PubMed           Abstract available Int J Infect Dis BERENDS MS, Homburg M, Kupers T, Meijer EN, et al Impact of Pre-Existing Comorbidities and Multimorbidities, Demography and Viral Variants on Post-Acute Sequelae of COVID-19 ('Long COVID') in Dutch Primary Care: A Retrospective Cohort Study. Int J Infect Dis. 2025 Apr 19:107912. doi: 10.1016/j.ijid.2025.107912. PubMed           Abstract...

#Influenza and Other Respiratory Viruses Research #References (by AMEDEO, April 26 '25)

  Antiviral Res ZHU Y, Gao Z, Feng X, Hu Y, et al Comprehensive preclinical characterization of IPB29, a pan-coronavirus fusion inhibitor under clinical trials. Antiviral Res. 2025;237:106154. PubMed           Abstract available BONNEUX B, Ceconi M, Stobbelaar K, Herschke F, et al Insights in the RSV L polymerase function and structure. Antiviral Res. 2025;237:106148. PubMed           Abstract available BRUN J, Arman BY, Hill ML, Kiappes JL, et al Assessment of repurposed compounds against coronaviruses highlights the antiviral broad-spectrum activity of host-targeting iminosugars and confirms the activity of potent directly acting antivirals. Antiviral Res. 2025 Feb 23:106123. doi: 10.1016/j.antiviral.2025.106123. PubMed           Abstract available ZIAN D, Iaconis D, Nenci S, Crusco A, et al The Efficiency of High-Throughput Screening (HTS) and in-silico data an...

#Biosecurity uptake and perceived #risk of avian #influenza among people in #contact with #birds in the #UK

Abstract Recent intercontinental spread of highly pathogenic avian influenza (HPAI) A(H5N1) among kept and wild birds and transmission to mammalian hosts , including cattle and humans has heightened the need to review public health risk assessments . Biosecurity is essential for limiting disease spread, but how widely practices are implemented is not fully known. Here, we report on the uptake of biosecurity measures using questionnaire data collected in 2024 from people in contact with birds in the UK (Avian Contact Study). Almost half of the sample were poultry farmers (104/225). We found hand washing after contact with birds was the most common biosecurity measure implemented (89%, 196/218), followed by using disinfecting footwear dips (78%, 170/218). Individuals in contact with a higher number of birds were more likely to use at least one PPE measure for the face or body (χ^2 (1, n=217) = 32.452, p<0.001) or at least one footwear-related PPE measure (Df=1, n=217, p<0.001), ind...

The expanding avian #influenza #panzootic: #skua die-off in #Antarctica

Abstract High pathogenicity avian influenza virus of subtype H5 (H5 HPAIV), clade 2.3.4.4b, invaded Antarctica in 2023 . Here we show that H5 HPAIV caused high mortality in a breeding colony of skuas at one of ten sites we visited in March 2024. By combined virological and pathological analyses, we found that H5 HPAIV caused multi-organ necrosis and rapid death in skuas . Taken together with recent data, skuas in Antarctica are at risk of continued mortality from H5 HPAIV infection, threatening their already small populations . Conversely, because of their wide distribution and ecological relevance, skuas may play a substantial role in the spread of the virus across Antarctica. Transdisciplinary surveillance is needed in coming years to monitor the impact of this poultry-origin disease on Antarctica's unique wildlife. Source: BioRxIV,  https://www.biorxiv.org/content/10.1101/2025.04.25.650384v1 ____

The #bat #influenza A virus subtype #H18N11 induces nanoscale MHCII clustering upon host #cell attachment

Abstract Prior to the discovery of bat influenza A virus (IAV) subtypes H17N10 and H18N11 , all IAVs were thought to bind sialic acid residues via hemagglutinin (HA) to mediate attachment and subsequent viral entry. However, H17 and H18 engage a proteinaceous receptor : the major histocompatibility complex class II (MHCII). The mechanistic details of this hitherto unknown protein-mediated entry are not understood. Given that conventional IAVs rely on multivalent binding to sialylated glycans , we hypothesized that bat HA similarly interacts with multiple MHCII molecules. Using photoactivated localization microscopy (PALM) on fixed and live cells, we demonstrate that bat IAV particles attach to pre-existing MHCII clusters and induce a further increase in cluster size upon binding. To measure the impact of viral attachment on the dynamics of MHCII, we employ an “inverse attachment” approach, immobilizing viral particles on coverslips before seeding live MHCII-expressing cells on top. Sin...

Single #influenza A viruses induce #nanoscale cellular #reprogramming at the virus-cell interface

Abstract During infection, individual virions trigger specific cellular signaling at the virus-cell interface , a nanoscale region of the plasma membrane in direct contact with the virus. However, virus-induced receptor recruitment and cellular activation are transient processes that occur within minutes at the nanoscale. Hence, the temporal and spatial kinetics of such early events often remain poorly understood due to technical limitations. To address this challenge, we develop a protocol to covalently immobilize labelled influenza A viruses on glass surfaces before exposing them to live epithelial cells . Our method extends the observation time for virus-plasma membrane association while minimizing viral modifications, facilitating live imaging of virus-cell interactions . Using single-molecule super-resolution microscopy, we investigate virus-receptor interaction showing that viral receptors exhibit reduced mobility at the virus-binding site, which leads to a specific local recepto...

A modelling #assessment for the #impact of #control measures on highly pathogenic avian #influenza #transmission in #poultry in Great #Britain

Abstract Since 2020, large-scale outbreaks of highly pathogenic avian influenza (HPAI) H5N1 in Great Britain have resulted in substantial poultry mortality and economic losses. Alongside the costs, the risk of circulation leading to a viral reassortment that causes zoonotic spillover raises additional concerns. However, the precise mechanisms driving transmission between poultry premises and the impact of potential control measures in Great Britain, such as vaccination, are not fully understood. We have developed a spatial transmission model for the spread of HPAI in poultry premises calibrated to infected premises data for the 2022--23 season using Markov chain Monte Carlo . Our results indicate that enhanced biosecurity measures and/or vaccination of the premises surrounding an identified infected premises can substantially reduce the overall number of infected premises. Our findings highlight that enhanced control measures could limit the future impact of HPAI on the poultry industr...

#USA, Monitoring for Avian #Influenza A(#H5) Virus In #Wastewater {as of April 25 '25}

{Excerpt} Time Period: April 13, 2025 - April 19, 2025 -- H5 Detection :  4 sites ( 1.0% ) -- No Detection :  406 sites ( 99.0% ) -- No samples in last week :  153 sites (...) Source: US Centers for Disease Control and Prevention,  https://www.cdc.gov/bird-flu/h5-monitoring/index.html?cove-tab=0 ____

#Vietnam - High pathogenicity avian #influenza #H5N1 viruses (#poultry) (Inf. with) - Immediate notification

A poultry farm in Quang Tri province. Source: WOAH,  https://wahis.woah.org/#/in-review/6440 ____

The #receptor binding properties of #H5Nx #influenza A viruses have evolved to promiscuously bind to avian-type mucin-like O-glycans

Abstract Highly pathogenic H5Nx influenza A viruses are causing unprecedented, season-independent outbreaks across avian and mammalian species, including dairy cattle, a novel reservoir. The sialoside-binding properties of influenza A hemagglutinin (HA) are strongly related to its ability to infect and transmit between hosts. Mucin-like O-glycans , omnipresent in respiratory tracts, have been understudied as viral receptors due to their complexity. To address this, we synthesized 25 O-linked glycans with diverse sialosides, including modifications by fucosides and sulfates. Our findings reveal that H5Nx 2.3.4.4b viruses uniquely bind core 3 sialyl-Lewisx and Sia-Gal-β3GalNAc, glycans not recognized by classical H5 or other avian viruses. By determining its crystal structure, we resolved the structural features of both structures in an H5 hemagglutinin (HA) from a 2016 2.3.4.4b virus. While these viruses do not bind human-type receptors , their promiscuous receptor specificity enhances ...

Emergence and interstate spread of highly pathogenic avian #influenza A(#H5N1) in dairy #cattle in #USA

Editor’s summary High-pathogenicity avian influenza subtype H5N1 is now present throughout the US , and possibly beyond. More cattle infections elevate the risk of the virus evolving the capacity to transmit between humans , potentially with high fatality rates . Nguyen et al. show that from a single transmission event from a wild bird to dairy cattle in December 2023, there has been cattle-to-poultry, cattle-to-peridomestic bird , and cattle-to-other mammal transmission. The movement of asymptomatic dairy cattle has facilitated the rapid dissemination of H5N1 from Texas across the US . Evolution within cattle, assessed using deep-sequencing data, has detected low-frequency sequence variants that had previously been associated with mammalian adaptation and transmission efficiency. —Caroline Ash Structured Abstract INTRODUCTION Highly pathogenic avian influenza (HPAI) viruses have critical consequences for animal health and the agricultural economy—and may have pandemic potential. HPAI ...

#Seroprevalence of #H9N2 and #H5 avian #influenza in mixed-species #poultry #farms in Northern #Benin

ABSTRACT Avian influenza is one of the major threats to poultry and human health in northern Benin , while mixed-species farming systems increase the risks of viral transmission. The present study estimated the seroprevalence of avian influenza subtypes H9N2 and H5 in indigenous chickens and guinea fowls in the Atacora and Donga regions. A total of 300 birds including 191 indigenous chickens and 109 guinea fowls, from six districts were sampled through a cross-sectional survey using systematic random sampling. Hemagglutination inhibition assay was used to detect antibodies, revealing an overall H9N2 seroprevalence of 41%, with 17.5% of samples testing positive for H5 . The seroprevalence of H9N2 was notably higher in guinea fowls (51.81% in Atacora and 52% in Donga) compared to chickens (34.95% in Atacora and 34.83% in Donga). H5 antibodies were found only in guinea fowls in Atacora (46.66%). The study also found that farms with both chickens and guinea fowls had a significantly higher...

#Remdesivir, mAb114, REGN-EB3, and #ZMapp partially rescue nonhuman #primates infected with a low passage #Kikwit variant of #Ebola virus

Abstract In 2018, a clinical trial of four investigational therapies for Ebola virus disease (EVD), known as the PALM trial , was conducted in the Democratic Republic of Congo . All patients received either the antiviral remdesivir (RDV) or a monoclonal antibody product : ZMapp, mAb114 (Ebanga), or REGN-EB3 (Inmazeb). The study concluded that both mAb114 and REGN-EB3 were superior to ZMapp and RDV in reducing mortality from EVD. However, the data suggested that some patients in the RDV and ZMapp groups might have been sicker at the time of treatment initiation. Here, we assessed the efficacy of each of these therapies in a uniformly lethal rhesus monkey model of EVD when treatment was initiated 5 days after Ebola exposure. Treatment with RDV, mAb114, REGN-EB3, and ZMapp each resulted in similar survival (approximately 40% ). Survival was associated with circulating viral load at treatment initiation. A trend of more escape mutants in the GP1 and GP2 domains was observed for the mAb114 ...

Investigating #Factors Driving Shifts in #Subtype #Dominance within #H5Nx Clade 2.3.4.4b High-Pathogenicity Avian #Influenza viruses

Abstract H5Nx clade 2.3.4.4b high-pathogenicity avian influenza viruses (HPAIVs) have decimated wild bird and poultry populations globally since the autumn of 2020. In the United Kingdom (UK) and in continental Europe , the H5N8 subtype predominated during the first epizootic wave of 2020/21, with few detections of H5N1 . However, during the second (2021/22) and third (2022/23) epizootic waves , H5N1 was the dominant subtype. The rapid shift in dominance from H5N8 to H5N1 was likely driven by a combination of virological, immunological, and/or host-related factors . In this study, we compared viral fitness and immunological responses in ducks , a key reservoir species, using dominant genotypes of H5N1 (genotype AB) and H5N8 (genotype A) from the second wave. While viral shedding dynamics were similar for both viruses, H5N8 was more pathogenic . Antigenic analysis of post-infection duck sera revealed that the haemagglutinin (HA) protein was antigenically similar across clade 2.3.4.4b H5...

Efficacy of #Baloxavir #Treatment in Preventing #Transmission of #Influenza

Abstract Background Baloxavir marboxil (baloxavir) rapidly reduces influenza virus shedding , which suggests that it may reduce transmission. Studies of treatment with neuraminidase inhibitors have not shown sufficient evidence that they prevent transmission to contacts. Methods We conducted a multicountry, phase 3b trial to assess the efficacy of single-dose baloxavir treatment to reduce influenza transmission from index patients to household contacts. Influenza-positive index patients 5 to 64 years of age were randomly assigned in a 1:1 ratio to receive baloxavir or placebo within 48 hours after symptom onset. The primary end point was transmission of influenza virus from an index patient to a household contact by day 5. The first secondary end point was transmission of influenza virus by day 5 that resulted in symptoms. Results Overall, 1457 index patients and 2681 household contacts were enrolled across the 2019–2024 influenza seasons; 726 index patients were assigned to the baloxa...

#Geographic and #age #variations in mutational processes in #colorectal #cancer

Abstract Colorectal cancer incidence rates vary geographically and have changed over time1 . Notably, in the past two decades, the incidence of early-onset colorectal cancer , affecting individuals under the age of 50 years, has doubled in many countries2-5. The reasons for this increase are unknown . Here, we investigate whether mutational processes contribute to geographic and age-related differences by examining 981 colorectal cancer genomes from 11 countries . No major differences were found in microsatellite unstable cancers, but variations in mutation burden and signatures were observed in the 802 microsatellite-stable cases. Multiple signatures, most with unknown etiologies , exhibited varying prevalence in Argentina, Brazil, Colombia, Russia , and Thailand , indicating geographically diverse levels of mutagenic exposure. Signatures SBS88 and ID18, caused by the bacteria-produced mutagen colibactin 6,7, had higher mutation loads in countries with higher colorectal cancer inciden...

#HK CHP investigates severe #paediatric case of #COVID19 co-infected with human #metapneumovirus

{Excerpt} The Centre for Health Protection (CHP) of the Department of Health today (April 23) received a report of a case of severe paediatric COVID-19 and human metapneumovirus (hMPV) infection and reminded the public to observe personal, hand and environmental hygiene at all times. High-risk individuals should receive a COVID-19 vaccination as soon as possible and receive booster doses at appropriate times to minimise the risk of serious complications and death after infection. The case involves an eight-month-old girl with good past health, who developed a fever and runny nose since April 19 and sought medical attention from a private doctor the next day. She developed cough and shortness of breath on April 21 and sought medical attention from another private doctor. She attended the Accident and Emergency Department of Hong Kong Adventist Hospital – Tsuen Wan on April 22 and was transferred to the Paediatric Intensive Care Unit of Princess Margaret Hospital for treatment on the sam...