Showing posts with label pandemic preparedness. Show all posts
Showing posts with label pandemic preparedness. Show all posts

Tuesday, August 18, 2026

A novel candidate #vaccine virus derived from #Japan's first #mammalian case of clade 2.3.4.4b #H5N1 highly pathogenic avian #influenza virus

 


Abstract

The development of candidate vaccine viruses (CVVs) for pre-pandemic preparedness requires attenuation of pathogenicity while maintaining immunogenicity. In this study, we developed and characterized NIID-002, a reassortant virus derived from A/Ezo red fox/Hokkaido/1/2022 (H5N1; clade 2.3.4.4b), to evaluate its suitability as a candidate vaccine. NIID-002 exhibited markedly reduced pathogenicity compared with its parental strain, while retaining broad antigenic reactivity and protein yield comparable to other clade 2.3.4.4b CVVs. In mammalian models, NIID-002 demonstrated strong attenuation, causing no lethal infection in mice and only minimal weight loss with limited viral replication in ferrets. Antisera raised against NIID-002 reacted broadly with recent wild-type H5N1 isolates, suggesting potential broad protection. Protein yield analysis confirmed a production efficiency comparable to that of other CVVs within the same clade, supporting its feasibility for large-scale vaccine manufacturing. Overall, NIID-002 fulfills the key requirements for the pandemic preparedness of CVV, combining reduced pathogenicity, broad antigenic reactivity, and adequate production efficiency. These findings highlight its potential as a candidate H5N1 vaccine and underscore the continued need for surveillance and refinement of influenza vaccine strategies to address evolving viral threats.

Source: 


Link: https://www.sciencedirect.com/science/article/abs/pii/S0264410X26008571?via%3Dihub

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#Community #engagement strategies for preventing recurrent #Nipah virus #outbreaks in #Bangladesh and #India: adapting a framework for outbreak preparedness and response

 


Abstract

The Nipah virus (NiV) infection is a highly fatal zoonotic disease with pandemic potential which has led to recurrent outbreaks in Bangladesh and India. While transmission pathways, including contaminated date palm sap and human-to-human spread, are increasingly identified, significant uncertainties remain. With no approved therapeutics or vaccines, prevention depends on addressing ecological and behavioural drivers of transmission. This viewpoint draws on selected evidence from NiV outbreaks and response to other zoonotic disease epidemics, such as Ebola, rabies, and the Marburg virus disease, we seek to foster discussion on why community engagement could be central to NiV prevention and preparedness. We highlight the relevance of community engagement through a spectrum of its intensity, which distinguishes between community-oriented, community-based, community-managed, and community-owned approaches. Adapting an existing model, we discuss how community engagement principles can be applied to tackle recurring NiV outbreaks in Bangladesh and India. By aligning interventions with sociocultural realities, community engagement can improve acceptability, enhance early detection, strengthen outbreak response, and support preparedness for future vaccine and therapeutic research. However, evidence specific to NiV remains limited and lessons from other diseases should be applied judiciously. In the absence of medical countermeasures, participatory, locally grounded approaches offer a sustainable pathway to reduce recurrent outbreaks and prevent future spillover events.

Source: 


Link: https://jogh.org/2026/jogh-16-03024

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Enhanced #Pathogenicity and Contact #Transmissibility of #Human-origin Avian #Influenza #H5N1 Clade 2.3.4.4b Genotype B3.13 Compared to D1.1 in #Ferrets

 


Abstract

Since its emergence in 2020, multiple genotypes of the H5N1 clade 2.3.4.4b have been identified, with B3.13 and D1.1 emerging in the USA as two major and concerning genotypes. However, their relative pathogenicity and transmissibility in mammals have not been fully elucidated. We compared the pathogenicity and transmissibility of the first two human H5N1 clade 2.3.4.4b cases caused by B3.13 in Texas (A/Texas/37/2024; HPhTX B3.13) and D1.1 in Louisiana (A/Louisiana/12/2024; HPhLA D1.1) in a ferret model of infection and transmission. HPhTX B3.13 infection resulted in more severe clinical disease and enhanced viral shedding, with evidence of increased transmission relative to HPhLA D1.1. Histopathological analysis revealed more extensive lung pathology in animals infected with HPhTX B3.13, consistent with increased viral loads and inflammatory responses. Importantly, both genotypes showed no significant differences in reactivity to ferret sera raised against candidate vaccine virus (CVV) strains, receptor binding properties, or neuraminidase (NA) activity and thermostability. Whole-genome sequencing revealed no adaptive mutations in HPhTX B3.13 following infection or transmission. In contrast, HPhLA D1.1 showed rapid acquisition of the mammalian-adaptive mutation E627K in infected ferrets and both E627K and Q194K in the only fatal contact animal. Both mutations were associated with enhanced polymerase activity and computational analyses suggested that they enhance interactions with the mammalian host factors ANP32A and B. Our findings indicate that B3.13 is already well adapted for mammalian infection and transmission whereas D1.1 retains evolutionary potential through the rapid acquisition of adaptive mutations, highlighting important genotype-specific differences relevant to zoonotic risk assessment and pandemic preparedness.


Competing Interest Statement

The A.G.-S. laboratory has received research support from Avimex, Dynavax, Pharmamar, and Accurius, outside of the reported work within the last three years. A.G.-S. has consulting agreements for the following companies involving cash and/or stock within the last three years: Castlevax, Amovir, Vivaldi Biosciences, Contrafect, Avimex, Pagoda, Accurius, Applied Biological Laboratories, Pharmamar, CureLab Oncology, CureLab Veterinary, Virofend, Prosetta and A.A.C.T., outside of the reported work. A.G.-S. has been an invited speaker in meeting events within the last three years organized by Seqirus, Novavax and Hipra. A.G.-S. is inventor on patents and patent applications on the use of antivirals and vaccines for the treatment and prevention of virus infections and cancer, owned by the Icahn School of Medicine at Mount Sinai, New York, outside of the reported work. The Icahn School of Medicine at Mount Sinai has licensed some of these inventions to Medimmune, Avimex, Leinco Technologies, Castlevax, Virofend, Kerafast, Cell Signaling, EMD Millipore, Genentech, Paratus and Nura Bio, and as a result receives financial compensation. Subject to Mount Sinai receiving such financial consideration, AG-S will receive a portion of that consideration pursuant to the terms of the Mount Sinai Intellectual Property Policy. All other authors declare no commercial or financial conflict of interest.


Funder Information Declared

NIH/NIAID, 75N93021C00014

Horizon Europe Program, KAPPA-FLU no. 101084171

Source: 


Link: https://www.biorxiv.org/content/10.64898/2026.08.10.744032v1

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Wednesday, August 12, 2026

Protective effect of #H5N8 stockpiled #vaccine against a virus genetically identical to a #human isolate of #bovine #H5N1 #influenza virus

 


Summary

Background

Since early 2024, highly pathogenic avian influenza A(H5N1) viruses of clade 2.3.4.4b have caused extensive outbreaks in dairy cattle in the United States, with spillover into mammalian species, including humans. A bovine-derived A(H5N1) virus isolated from a human case retains high pathogenicity and transmissibility in mammalian models, highlighting its pandemic potential. Stockpiled pre-pandemic influenza vaccines are intended to provide early protection before strain-matched vaccines are available; however, their protective efficacy against bovine A(H5N1) viruses has not been directly evaluated in vivo.

Methods

In this study, we assessed the protective efficacy of an AS03-adjuvanted A/Astrakhan/3212/2020 (H5N8) clade 2.3.4.4b-based influenza vaccine stockpiled in Japan using mouse and ferret models. Vaccinated and unvaccinated animals were challenged with a virus genetically identical to a human isolate of bovine A(H5N1) virus. Neutralising antibody responses, viral replication in organs, and survival were evaluated.

Findings

Vaccination with the AS03-adjuvanted A(H5N8)-based stockpiled vaccine induced robust neutralising antibody responses in both animal models, significantly suppressed viral replication, and conferred complete protection against lethal challenge. In contrast, all unvaccinated mice and ferrets succumbed to infection. These findings demonstrate that the AS03-adjuvanted A(H5N8)-based stockpiled vaccine provides strong cross-protective efficacy against bovine A(H5N1) viruses.

Interpretation

An AS03-adjuvanted A(H5N8)-based vaccine stockpiled in Japan could serve as an immediate countermeasure against bovine A(H5N1) viruses during the early phase of a pandemic.

Funding

This work was supported by grants from the Japan Program for Infectious Diseases Research and Infrastructure (JP20wm0125002) and the Japan Initiative for World-leading Vaccine Research and Development Centers (JP223fa627001) from the Japan Agency for Medical Research and Development.

Source: 


Link: https://www.thelancet.com/journals/ebiom/article/PIIS2352-3964(26)00314-2/fulltext

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Thursday, August 6, 2026

Heterologous prime-boost #vaccination against #H5 avian #influenza: Safety and immunogenicity of a MF59-adjuvanted, cell-culture derived #H5N6 vaccine

 


ABSTRACT

With increasing H5 avian influenza cases reported globally and the potential for pandemic emergence, induction of cross-reactive antibody responses may represent an important attribute of an effective vaccine. This phase 2 extension study evaluated immunogenicity and safety of MF59-adjuvanted, cell culture-derived H5N6 vaccine (aH5N6c) in adults primed with MF59-adjuvanted, cell culture-derived H5N1 vaccine (aH5N1c) and in unprimed adults. Adults previously primed with two doses of aH5N1c in the parent study V89_18 were randomized to receive two aH5N6c doses (Group 1) or one aH5N6c and one placebo (Group 2) 3 weeks apart. Unprimed adults received two aH5N6c doses (Group 3). Immunogenicity was assessed by hemagglutination inhibition (HI) and microneutralization (MN) assays against the priming (H5N1) and booster (H5N6) strains on Days 1, 8, 22, 43, and 202. Among 258 exposed participants, primed subjects (Groups 1 and 2) showed higher HI geometric mean titers against both strains than unprimed (Group 3) subjects, with MN responses similarly enhanced. Heterologous H5N1 responses were robust in primed subjects (Day 43 HI GMTs: 333–343; seroconversion rates >89%) but minimal in unprimed subjects, with responses persisting to Day 202. Solicited adverse events were mild or moderate, comparable between groups, and consistent with other MF59-adjuvanted pandemic vaccines; no vaccine-related serious adverse events occurred. Heterologous H5N6 booster vaccination in H5N1-primed adults elicited strong cross-reactive immunity against the priming strain, demonstrating long-lasting immune memory for at least 6 y and supporting heterologous prime-boost strategies for pandemic preparedness against emerging H5 outbreaks.

Source: 


Link: https://www.tandfonline.com/doi/full/10.1080/21645515.2026.2712791

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Tuesday, August 4, 2026

A One-Shot Multivalent Live-Attenuated Candidate #Influenza #Vaccine against Divergent #Zoonotic #H5N1 Clades

 


Abstract

The continued emergence of genetically diverse high pathogenicity avian influenza (HPAI) H5N1 viruses with zoonotic potential highlights the urgent need for developing vaccines capable of providing broad protection against multiple circulating clades. Here, we developed a one-shot, multivalent, live-attenuated influenza vaccine (LAIV) based on the temperature-sensitive (ts), cold-adapted (ca), and attenuated (att) influenza A/Ann Arbor/6/1960 master donor virus (MDV) that incorporates the hemagglutinin (HA) and neuraminidase (NA) glycoproteins from representative clades 2.3.4.4b (A/Louisiana/12/2024), 2.3.2.1a (A/Victoria/149/2024), and 2.3.2.1e (A/Cambodia/2302009/2023) H5N1 viruses. A single intranasal (IN) immunization of C57BL/6 mice with the multivalent LAIV elicited robust humoral immune responses, with immune sera exhibiting broad cross-reactivity against antigens from all three H5N1 clades included in the vaccine. Following homologous viral challenge, vaccinated C57BL/6 mice were completely protected from disease, demonstrating the immunogenicity and protective efficacy of the multivalent LAIV. By simultaneously targeting antigenically distinct H5N1 lineages with pandemic potential, this strategy expands antigenic coverage within a single LAIV to confirm pan-H5N1 protection. Together, these findings support the development and implementation of this multivalent LAIV as a broadly protective pan-H5N1 LAIV for pandemic preparedness.


Competing Interest Statement

The A.G.-S. laboratory has received research support from Avimex, Dynavax, Pharmamar, and Accurius, outside of the reported work within the last three years. A.G.-S. has consulting agreements for the following companies involving cash and/or stock within the last three years: Castlevax, Amovir, Vivaldi Biosciences, Contrafect, Avimex, Pagoda, Accurius, Applied Biological Laboratories, Pharmamar, CureLab Oncology, CureLab Veterinary, Virofend, Prosetta and A.A.C.T., outside of the reported work. A.G.-S. has been an invited speaker in meeting events within the last three years organized by Seqirus, Novavax and Hipra. A.G.-S. is inventor on patents and patent applications on the use of antivirals and vaccines for the treatment and prevention of virus infections and cancer, owned by the Icahn School of Medicine at Mount Sinai, New York, outside of the reported work. The Icahn School of Medicine at Mount Sinai has licensed some of these inventions to Medimmune, Avimex, Leinco Technologies, Castlevax, Virofend, Kerafast, Cell Signaling, EMD Millipore, Genentech, Paratus and Nura Bio, and as a result receives financial compensation. Subject to Mount Sinai receiving such financial consideration, AG-S will receive a portion of that consideration pursuant to the terms of the Mount Sinai Intellectual Property Policy. All other authors declare no commercial or financial conflict of interest.

Source: 


Link: https://www.biorxiv.org/content/10.64898/2026.08.02.742385v1

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Thursday, July 16, 2026

#Spain, Ministry of Health is strengthening #prevention, #preparedness and response to #animal-borne #influenza with a national plan (Min. Health, July 16 '26)

 


    Madrid, July 16, 2026.- The Public Health Commission has approved the State Plan against infections by influenza viruses of zoonotic origin: Prevention, Surveillance and Control, which establishes a common framework for prevention, surveillance, early detection and response to influenza viruses that circulate in animals and can be transmitted to people.

    The Plan adopts the "One Health" approach and establishes a joint response across the fields of human health, animal health, and the environment. Its objective is to improve coordination among the different sectors at the national, regional, and local levels, and to ensure that epidemiological, microbiological, and environmental information is integrated, up-to-date, and readily available to facilitate the early implementation of control measures.

    The document has been coordinated by the Center for Coordination of Health Alerts and Emergencies (CCAES) of the Ministry of Health and prepared jointly with the Ministries of Agriculture, Fisheries and Food and for Ecological Transition and the Demographic Challenge, the Carlos III Health Institute, the Spanish Agency for Food Safety and Nutrition and other units involved in the prevention and management of these risks.

    Zoonotic influenza viruses circulate among animals. Transmission to humans remains infrequent and is usually linked to direct contact with infected animals, their secretions, or contaminated environments. However, their ability to mutate and exchange genetic material necessitates continuous surveillance, especially given the increased detection of these viruses in various mammal species.

    The Plan organizes the actions into four scenarios , which allow the measures to be progressively adapted to the epidemiological situation of each territory.

    Scenario 0 corresponds to a situation with no detected infections in animals or people and focuses on ordinary actions of prevention, surveillance, training and maintenance of diagnostic capabilities.

    Scenario 1 is activated upon detection of outbreaks in wild or captive animals. It distinguishes between isolated outbreaks in birds, multiple outbreaks distributed across a territory, and detections in wild mammals.

    Scenario 2 considers outbreaks in domestic animals and also differentiates between isolated outbreaks in birds, multiple outbreaks, and detections in domestic mammals.

    Finally, scenario 3 applies when a human infection is identified. In this case, a distinction is made between cases with known exposure to animals or contaminated environments, those where no risk exposure is identified, and cases associated with contact with another infected person, which would imply possible limited human-to-human transmission.

    The scenarios are not mutually exclusive and may be applied simultaneously in the same territory. Each autonomous community will conduct its own risk assessment to determine the necessary measures in each affected province, community, or geographical area.

    The Plan envisions the creation of a Permanent State Committee for Coordination and Monitoring , chaired and technically coordinated by the CCAES, responsible for reviewing preparedness and response measures, promoting common protocols, conducting joint risk assessments, and evaluating the Plan's effectiveness. Furthermore, it recommends that the autonomous communities establish equivalent bodies to coordinate actions related to public health, animal health, the environment, food safety, and occupational health.

    This body will include representatives from the competent departments in public health, animal health, biodiversity, food safety, occupational health, medicines and health products and epidemiological and microbiological surveillance, as well as from the autonomous communities, the Spanish Federation of Municipalities and Provinces and experts.

    Human health measures focus especially on people who, due to their professional activity, may come into contact with infected animals, their secretions or contaminated materials, such as livestock farm personnel, veterinary professionals, environmental agents or zoo workers.

    Companies must assess the risk, provide the necessary protective equipment, and ensure health monitoring. Occupational risk prevention services will identify and monitor exposed personnel in the event of outbreaks in animals and, where appropriate, may recommend PCR tests, preventive antiviral treatment, or vaccination against zoonotic viruses.

    The Plan also maintains the recommendation for seasonal flu vaccination for those who work in direct contact with animals, with the aim of reducing the risk of coinfection by human and animal flu viruses.

    In the animal sector , the Plan strengthens surveillance of wild and domestic birds and mammals, as well as genomic analysis of viruses to detect changes that could increase their transmissibility. In the event of outbreaks on farms, biosecurity measures, movement controls, confinement, and, where appropriate, vaccination will be implemented.

    In parks and urban or peri-urban areas, protocols will be established to safely remove sick or dead animals, clean and disinfect affected areas, and inform the public. It is recommended not to touch or handle them and to report their presence to the appropriate authorities.

    The Plan incorporates risk communication and community participation as one of its five main components. To this end, an inter-institutional communication group will be established, websites with updated information will be created, and campaigns will be developed targeting both the general public and the professional sectors with the greatest exposure.

    Media and social media will also be monitored to detect and respond to rumors, false content, or unverified information. In higher-risk scenarios, an official spokesperson will be appointed, information will be updated daily, and, when necessary, a citizen hotline will be activated.

    The Permanent State Committee will develop the indicators that will allow the evaluation of preparedness and response, as well as compliance with the Plan in its various components and at the state and regional levels.

    In the last year, more than 150 outbreaks of avian influenza have been detected in Spain, mostly in wild birds, although outbreaks have also been recorded in poultry, leading to the culling of thousands of animals. Despite the increased circulation of the virus among birds, Spain has not registered any human cases of avian influenza to date. Regarding swine influenza, three human cases of infection have been identified in Spain since 2009.

    The new Plan will strengthen prevention, early detection and coordinated response to any changes in the epidemiological situation.

Source: 


Link: https://www.sanidad.gob.es/gabinete/notasPrensa.do?id=6965

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Occupationally Exposed and General #Population #Antibody #Profiles to #Influenza A Viruses Circulating in #Swine as Indication of Zoonotic #Risk

 


Abstract

Persons with occupational exposure to swine might be at disproportionate risk for zoonotic swine influenza A virus. To evaluate human antibody responses, we tested serum or plasma from swine veterinarian, farm employee, and general population cohorts by hemagglutination inhibition assays against representative swine and human seasonal influenza vaccine strains. We analyzed hemagglutination inhibition data by antigenic cartography to assess strain relationships and reproduction number modeling to evaluate pandemic potential using age-stratified immunity profiles. Occupationally exposed groups had lower human seasonal vaccine uptake (45.5% vs. 70%) and lower odds of seropositivity to several H1 and H3 strains from swine than did general population cohorts. One swine strain exhibited significant antigenic drift (3.62 antigenic units) from its nearest vaccine strain. Multiple strains required lower reproduction number thresholds for pandemic spread (1.09–1.35) than recorded pandemic strains (1.46–1.80), demonstrating that population immunity gaps heighten zoonotic risk to circulating swine H1 and H3 strains.

Source: 


Link: https://wwwnc.cdc.gov/eid/article/32/8/25-1995_article

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Saturday, July 11, 2026

Preparing for the Next #Pandemic: Learning From #COVID19 to Build What Comes Next

 


Abstract

WHO's efforts to strengthen pandemic preparedness—grounded in what the world learned during COVID-19 and what today's outbreaks of avian influenza, Hantavirus and Ebola are teaching us.

Source: 


Link: https://academic.oup.com/ofid/article/13/7/ofag348/8728458

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Thursday, July 9, 2026

Immunoinformatics-Guided Design and In Silico Evaluation of a Multi-Epitope #Vaccine Against #Influenza A #H10N5 and #H3N2 Strains Based on HA and NA Proteins

 


Abstract

Influenza A viruses H3N2 and H10N5 represent, respectively, a persistently dominant seasonal pathogen and a newly documented zoonotic threat with the latter strain variants responsible for the first confirmed human fatality in January 2024, yet no vaccine platform currently addresses co-protection against both subtypes within a unified immunogen. We report here the immunoinformatics based vaccine design and multi-layered computational validation of a 419-amino-acid multi-epitope subunit vaccine construct targeting conserved hemagglutinin (HA) and neuraminidase (NA) antigens identified through multiple sequence alignment of the avian H10N5 (A/swine/Hubei/10/2008) and H3N2 human reference strain sequences to identify viral agents undergoing mammalian adaptations. Linear B-cell, cytotoxic T lymphocyte (CTL), and helper T lymphocyte (HTL) epitopes were predicted using ABCpred, BCEpred, BepiPred 2.0, NetMHCpan 2.1, and NetMHCpan 4.0, then filtered through VaxiJen 3.0, AllerTOP v2.1, and ToxinPred to retain only antigenic, non-allergenic, non-toxic candidates. The final construct, incorporating an avian β-defensin N-terminal adjuvant with GPGPG, AAY, and EAAAK linkers, exhibited a molecular weight of 43.9 kDa, instability index of 31.15, and SOLPro solubility probability of 0.763. Tertiary structure modeling via I-TASSER and GalaxyRefine achieved 84.4% Ramachandran-favored residues. Molecular docking against TLR3 and TLR7 yielded binding free energies of −16.1 and −16.8 kcal/mol with picomolar dissociation constants. Molecular dynamics simulations confirmed complex stability over extended trajectories. Furthermore, codon optimization produced a Codon Adaptation Index of 1.0 for E. coli K12 expression. In silico immune simulation demonstrated robust activation of humoral and cellular immunity including elevated IgG1, IgM, IFN-γ, IL-2, rapid NK cell expansion, and broad B-cell clonal diversity. These findings establish a computationally validated candidate capable of providing protection against influenza in multiple host organisms, warranting experimental advancement.


Competing Interest Statement

The authors have declared no competing interest.

Source: 


Link: https://www.biorxiv.org/content/10.64898/2026.07.03.736294v1

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Friday, July 3, 2026

#Vaccine #strategies and #development before and during the 1968 #H3N2 #influenza #pandemic

 


Abstract

Nearly 60 years ago, in 1968, the global population was confronted with the emerging pandemic influenza A virus (IAV) subtype H3N2 (1968 H3N2pdm). An estimate of up to two million fatalities have been linked to 1968 H3N2pdm, and the H3N2 subtype continues to circulate as seasonal IAV among humans until today. The last IAV pandemic dates back to the year 2009 but concerns about a new IAV pandemic in the near future are increasing. The global spread of H5N1 highly pathogenic avian influenza virus and its spill-over into new mammalian hosts, discovery of novel influenza A virus with zoonotic or even pandemic potential, as well as seasonal influenza viruses undergoing antigenic changes necessitate constant vigilance. Here, we highlight the proactive actions, precautionary measures and vaccination strategies used during the 1968 H3N2 IAV pandemic. Our review highlights the emergence and spread of 1968 H3N2pdm over the course of the pandemic, alongside a delineation of vaccine development before, during and after the 1968 pandemic. Updating these strategies in the context of new findings combined with our experiences during the coronavirus disease 2019 (COVID-19) pandemic is necessary to improve preparedness for the next pandemic. Influenza viruses with zoonotic potential will remain a constant threat to public health, and improving countermeasures and communication to the public is key to limit the pandemic ramifications.

Source: 


Link: https://www.sciencedirect.com/science/article/abs/pii/S0264410X26006869?via%3Dihub

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Wednesday, July 1, 2026

#Andes Virus on a Cruise #Ship, what it Tells us About the #Global #Pandemic #Preparedness Agenda

 


Summary

The outbreak of hantavirus disease caused by Andes virus aboard a cruise ship is a reminder of the challenges posed by emerging diseases in the modern era. While Andes virus-associated disease can be particularly severe, it is unlikely to spread extensively beyond the current number of cases or emerge as a large epidemic, especially if public health measures are followed. Nonetheless, the outbreak exemplifies the complexity of international outbreak response with differences in national preparedness frameworks and the rapid spread of mis-/disinformation. We discuss this outbreak in the context of global epidemic and pandemic preparedness and emphasize the importance of sustained, inclusive global collaborative One Health approaches to preparedness and response. We stress the urgent need for global coordination, discuss specific challenges, and provide recommendations for further strengthening of global preparedness.

Source: 


Link: https://www.thelancet.com/journals/lanepe/article/PIIS2666-7762(26)00167-5/fulltext

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Friday, June 12, 2026

A neutralizing #nanobody targeting a conserved lateral patch on HA1 confers #protection against multiple #H7 avian #influenza viruses

 


ABSTRACT

Human infections with H7 avian influenza viruses (AIVs) have been documented globally, involving multiple subtypes and geographic regions. However, effective therapeutics targeting H7 influenza viruses remain limited. Here, a panel of nanobodies targeting the HA1 domain of hemagglutinin (HA) was identified by yeast two-hybrid (Y2H) screening, and six candidates were subsequently validated to exhibit hemagglutination inhibition (HI) activity. Of these, a subset also displayed virus microneutralization (MN) activity, while all showed binding activity in ELISA assays. Among them, Nb74 exhibited inhibitory activity against four Chinese recombinant vaccine-matched strains (Rv1–Rv4), which were generated based on the HA sequences of the corresponding inactivated vaccine strains H7-Re1 to H7-Re4. The HI-IC50 values were 0.23, 0.57, 3.65, and 43.75 µg/mL, respectively, and the MN-IC50 values for Rv1–Rv3 were 0.02, 0.06, and 1.09 µg/mL. It also retained activity against diverse clinical isolates although HI potency varied among strains. In mouse challenge experiments, intratracheal administration of Nb74 conferred robust protection, achieving 100% and 80% survival against Rv1 and Rv2, respectively, when administered prophylactically (2 mg/kg) or therapeutically (4 mg/kg). Treated mice showed accelerated body weight recovery, reduced lung viral load, and alleviated pulmonary pathology. Mechanistic analyses indicated that Nb74 neutralizes virus by blocking viral attachment to the host. Furthermore, combined hydrogen-deuterium exchange mass spectrometry (HDX-MS) with escape mutant analysis mapped its epitope to a conserved lateral patch on the HA1 subunit, consistent with a conformational epitope. Overall, these results demonstrate the therapeutic promise of intratracheally delivered Nb74 and provide insights for H7 AIVs vaccine design.

Source: 


Link: https://journals.asm.org/doi/10.1128/jvi.00563-26

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Immunogenicity and safety of AS03-adjuvanted A/Astrakhan/3212/2020 #H5N8 -like #influenza #vaccine in adults: Phase 1/2, observer-blinded, randomized trial

 


ABSTRACT

Influenza pandemics arise from novel influenza A viruses. Recent emergence of a new clade (2.3.4.4.b) of the highly pathogenic H5N1 in animals and humans highlighted its pandemic potential. We evaluated the immunogenicity and safety of GSK’s AS03-adjuvanted H5N8 vaccine in adults. In this phase 1/2, observer-blinded, age-stratified, randomized trial, healthy US adults (age, ≥18 y) received two intramuscular doses of hemagglutinin antigen (3.75 or 7.50 μg) with AS03A or AS03B, administered 21 d apart. Immunogenicity – seroprotection rates (SPRs), seropositivity, geometric mean titers (GMTs), geometric mean fold rise (GMFR), and seroconversion rates (SCRs) – was evaluated on day 43 using hemagglutination inhibition (HI) and microneutralization (MN) assays. Safety was monitored throughout the study. Of 520 enrolled participants, 518 were vaccinated. On day 43, the US Food and Drug Administration’s (FDA) Center for Biologics Evaluation and Research criteria for influenza vaccines were met. HI SPRs, seropositivity rates, SCRs, GMTs, and GMFR appeared to be higher in the AS03A vs AS03B group. Immune responses were generally higher in younger (aged 18–64 y) vs older (aged ≥65 y) adults. Immune responses were also detected in MN assays, with a correlation between HI and MN responses on day 43 across age groups and vaccine formulations. Safety was acceptable, with no increase in adverse events post-dose 2. Reactogenicity appeared more common in younger adults. The antigen-sparing potential of AS03 was demonstrated, with an acceptable safety profile. The benefit/risk profile was favorable for all formulations tested, including 3.75 µg AS03A (licensed in the US).


ClinicalTrials.gov registration: NCT05975840.

Source: 


Link: https://www.tandfonline.com/doi/full/10.1080/21645515.2026.2649314

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Wednesday, June 3, 2026

CEIRR #Risk #Assessment Pipeline executive reports on #H5N1 highly pathogenic avian influenza 2.3.4.4b, swine H1 1B.2, and #H9N2 low pathogenicity avian influenza B4.7.2

 


ABSTRACT

The Centers of Excellence for Influenza Research and Response (CEIRR) Risk Assessment Pipeline (RAP) integrates surveillance, phenotypic analysis, and computational modeling across six CEIRR centers to evaluate the pandemic potential of influenza A viruses. By generating coordinated data sets from wild and domestic animals and linking them to viral evolution and functional traits, CEIRR RAP supports the Centers for Disease Control and Prevention’s and the World Health Organization’s risk-assessment efforts. The RAP’s data packages thereby enable evidence-based prioritization of global influenza preparedness and response strategies.

Source: 


Link: https://journals.asm.org/doi/10.1128/jvi.00545-26

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Saturday, May 30, 2026

#Outbreak at #Sea: The MV Hondius #Hantavirus #Cluster as a Sentinel for Global #Pandemic Readiness

 


{Summary}

The South Atlantic promises crystalline isolation. But the Dutch-flagged MV Hondius—an expedition vessel carrying 147 passengers and crew from 23 nations—harbored something else entirely between the Southern Cone and Antarctica [1, 2]. An invisible passenger. Epidemiologists trace this outbreak directly to dry land, theorizing the index case inhaled aerosolized rodent excreta during a Southern Cone bird-watching excursion [1].

(...)

Source: 


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Thursday, May 28, 2026

Assessing #Evidence to Guide Primary #Prevention of #Pathogen X

 


Abstract

Primary prevention includes interventions that prevent the initial occurrence of disease; in the context of pandemic origins, one class of primary preventative interventions involves reducing the risk of zoonotic pathogen spillover. Pandemics are rare events, therefore data on spillover events of known pandemic pathogens are also rare. In contrast, many zoonotic viruses spill over frequently but fail to spread efficiently between humans. We consider whether insights from frequent spillovers of poorly-spreading viruses should be used to inform primary prevention strategies aimed at viruses that spill over rarely but spread well human-to-human. We propose a set of principles to steer future research and guide deployment of preventative strategies. We believe that a precautionary approach, grounded in evidence from viruses that spill over frequently, offers the most practical empirical foundation for guiding primary spillover prevention.

Source: 


Link: https://wwwnc.cdc.gov/eid/article/32/6/26-0293_article

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Friday, May 22, 2026

Epidemiological #surveillance against the #Andes virus: have we learned anything after #COVID19?

 


Summary

Recent outbreaks associated with Andes hantavirus have reignited the international debate on healthcare preparedness for hantaviruses with documented human-to-human transmission. Unlike other orthohantaviruses, Andes hantavirus has demonstrated human-to-human transmission in certain epidemiological contexts, including household and hospital settings. The recent emergence of cases linked to multinational outbreaks has prompted new assessments and recommendations from international public health organizations.

This manuscript presents an epidemiological reflection on the current challenges of surveillance against emerging hantaviruses, drawing on the experience gained during the COVID-19 pandemic. It also reviews aspects related to zoonotic surveillance, molecular monitoring, early detection, and integrated One Health approaches applied to preparedness for future emerging threats.

The available evidence suggests the need to strengthen surveillance systems capable of integrating human, environmental, and animal information to improve the response to complex epidemiological scenarios associated with emerging hantaviruses.

Source: 


Link: https://ojs.sanidad.gob.es/index.php/resp/article/view/1824

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Wednesday, May 13, 2026

Pre-existing systemic and #nasal #antibodies against avian #H5 #influenza A viruses vary according to #childhood imprinting

 


Abstract

Avian influenza A viruses (IAV) pose a constant pandemic threat, with the recent 2.3.4.4b clade of the H5 subtype causing high pathogenicity and spreading across animal species and geographic locations. Understanding human pre-existing immunity to avian H5 IAV can inform on population susceptibility, a critical aspect of pandemic preparedness. To that end, we analysed the IAV HA-specific antibodies across individuals born between 1928-1999 with different early life exposures to IAV subtypes. Individuals born prior to 1957 had the highest pre-existing serum antibodies to group 1 HA antigens, including the 2.3.4.4b H5 and a group 1 HA stem antigen. These birth-year-specific patterns were not reflected in the limited pre-existing serum neutralising antibodies detectable against a 2.3.4.4b H5 IAV or in H5-specific memory B cell populations. They were however evident in pre-existing nasal IgG and IgA titres to H5, which were greater in individuals born prior to 1957. Our findings demonstrate that the immunological biases afforded by early life exposure extend to antibodies detected in the nasal mucosa, the site of IAV replication.

Source: 


Link: https://www.biorxiv.org/content/10.64898/2026.05.08.723737v1

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Monday, April 27, 2026

Evaluation of Cross-Immunogenicity of #Ferret #Antisera Following Immunization with #H5N1 #Vaccine Strains

 


Abstract

Background

Highly pathogenic avian influenza H5N1 viruses of clade 2.3.4.4b have spread globally since 2021, causing extensive outbreaks in avian populations and repeated spillovers into diverse mammalian hosts, including humans. These cross-species transmission events highlight ongoing pandemic risks and underscore the need for vaccine strategies that reflect viral evolution at the human–animal interface. Despite the availability of licensed H5 vaccines and newly recommended World Health Organization (WHO) candidate vaccine viruses (CVVs), the extent to which these vaccines elicit cross-reactive antibody responses against contemporary clade 2.3.4.4b viruses, including mammalian spillover isolates of avian origin, remains incompletely characterized

Method

In this study, ferret antisera were generated using four WHO-recommended H5 CVVs, including a clade 1 strain (A/Vietnam/1194/2004) and three clade 2.3.4.4b strains (A/Astrakhan/3212/2020, A/American wigeon/South Carolina/22-000345-001/2021, and A/Ezo red fox/Hokkaido/1/2022), formulated with alum adjuvant to reflect licensed vaccine formulation used in national preparedness programs. Antibody responses and cross-reactive activity were evaluated using hemagglutination inhibition (HI) and microneutralization (MN) assays against homologous vaccine strains and a feline-origin clade 2.3.4.4b H5N1 field isolate from Korea, A/Feline/Korea/SNU-01/2023. 

Results

Antisera induced by clade 2.3.4.4b CVVs showed cross-reactive antibody responses against homologous and heterologous clade 2.3.4.4b viruses and demonstrated measurable HI and MN responses against the feline-origin field isolate. In contrast, antisera raised against the clade 1 Vietnam CVV exhibited limited cross-reactivity against clade 2.3.4.4b viruses. Overall, clade 2.3.4.4b CVVs generally showed higher antibody responses than the clade 1 vaccine strain across multiple panels. 

Conclusions

These findings provide descriptive insights into antigenic differences between clade 1 and clade 2.3.4.4b viruses and support the antigenic relevance of clade 2.3.4.4b CVVs for contemporary H5N1 strains. This study highlights the importance of ongoing antigenic evaluation to inform vaccine strain selection within a One Health framework.

Source: 


Link: https://www.mdpi.com/2076-393X/14/4/301

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