{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T04:30:14Z","timestamp":1786681814365,"version":"build-2736575974"},"reference-count":34,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T00:00:00Z","timestamp":1786492800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100020166","name":"Flu Lab","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100020166","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/027hgk366","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background\/objectives: The emergence of highly pathogenic avian influenza A (H5N1) virus infections in dairy cattle in the United States revealed a novel mammalian host and a potential transmission pathway involving raw milk and dairy production systems. Sustained circulation of H5N1 in dairy herds is of concern because ongoing viral adaptation in mammals may increase the risk of efficient mammalian transmission and subsequent zoonotic spread. In response to this emerging threat, we developed a chimpanzee adenovirus (ChAd)-vectored vaccine expressing the haemagglutinin 5 antigen (H5HA) from the dairy cattle isolate A\/dairy cattle\/Texas. Methods: Lactating dairy cows were vaccinated by either intramuscular (N = 3) or intranasal administration (N = 3). H5HA clade 2.3.4.4b antibodies in cow\u2019s milk and sera were evaluated by ELISA. Hemagglutination and neutralisation capacity were also evaluated. Results: IgG and IgA H5HA-specific antibodies were detected in serum and milk from parenterally vaccinated animals, demonstrating the induction of a systemic immune response. The neutralising antibody responses elicited were only detected in serum of cows vaccinated via the intramuscular route. Conclusions: These preliminary findings support the feasibility of ChAd-vectored vaccination as a strategy to induce humoral immunity in cattle against emerging H5N1 influenza A viruses. Cross-reactive antibody responses against both A\/dairy cattle\/Texas\/24-008749_001\/2024 and A\/Ibis\/Egypt\/RLQP-229S\/2022 support the capacity of the vaccine to recognise antigenically related H5N1 clade 2.3.4.4b viruses circulating in mammalian and avian reservoirs. Further studies of vaccine efficacy and the immunological mechanism of protection should now be undertaken with the aim of reducing viral transmission and milk-associated shedding in dairy herds.<\/jats:p>","DOI":"10.3390\/vaccines14080691","type":"journal-article","created":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T07:57:26Z","timestamp":1786521446000},"page":"691","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Assessment of Humoral Immunogenicity of ChAdOx1 H5 HA Influenza Vaccine for Dairy Cattle"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1692-9987","authenticated-orcid":false,"given":"Barbara","family":"Dema","sequence":"first","affiliation":[{"name":"Pandemic Sciences Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7TY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marta","family":"Ulaszewska","sequence":"additional","affiliation":[{"name":"Pandemic Sciences Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7TY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alice","family":"Lilley","sequence":"additional","affiliation":[{"name":"Worldwide Influenza Centre, Francis Crick Institute, London NW1 1AT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8066-4514","authenticated-orcid":false,"given":"Abi","family":"Lofts","sequence":"additional","affiliation":[{"name":"Worldwide Influenza Centre, Francis Crick Institute, London NW1 1AT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roo","family":"Bhasin","sequence":"additional","affiliation":[{"name":"Pandemic Sciences Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7TY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruth","family":"Harvey","sequence":"additional","affiliation":[{"name":"Worldwide Influenza Centre, Francis Crick Institute, London NW1 1AT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Piyada","family":"Supasa","sequence":"additional","affiliation":[{"name":"Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-4596-253X","authenticated-orcid":false,"given":"Mat\u011bj","family":"Hlav\u00e1\u010d","sequence":"additional","affiliation":[{"name":"Pandemic Sciences Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7TY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-1813-0557","authenticated-orcid":false,"given":"Susan J.","family":"Morris","sequence":"additional","affiliation":[{"name":"Pandemic Sciences Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7TY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8695-4697","authenticated-orcid":false,"given":"Richard E.","family":"Booth","sequence":"additional","affiliation":[{"name":"Pathobiology and Population Sciences, Royal Veterinary College, London NW1 0TU, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7448-8200","authenticated-orcid":false,"given":"Alexander M. P.","family":"Byrne","sequence":"additional","affiliation":[{"name":"Worldwide Influenza Centre, Francis Crick Institute, London NW1 1AT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicola","family":"Lewis","sequence":"additional","affiliation":[{"name":"Worldwide Influenza Centre, Francis Crick Institute, London NW1 1AT, UK"},{"name":"Biological Services Unit, Royal Veterinary College, London NW1 0TU, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-8221-660X","authenticated-orcid":false,"given":"Alex","family":"McSloy","sequence":"additional","affiliation":[{"name":"Biological Services Unit, Royal Veterinary College, London NW1 0TU, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6823-9750","authenticated-orcid":false,"given":"Sarah C.","family":"Gilbert","sequence":"additional","affiliation":[{"name":"Pandemic Sciences Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7TY, UK"},{"name":"CAMS Oxford Institute, Chinese Academy of Medical Sciences & Peking Union Medical College, University of Oxford, Oxford OX3 7BN, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"913","DOI":"10.1038\/s41586-024-08166-6","article-title":"Dairy cows inoculated with highly pathogenic avian influenza virus H5N1","volume":"637","author":"Baker","year":"2025","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Sreenivasan, C.C., Li, F., and Wang, D. (2024). Emerging Threats of Highly Pathogenic Avian Influenza A (H5N1) in US Dairy Cattle: Understanding Cross-Species Transmission Dynamics in Mammalian Hosts. Viruses, 16.","DOI":"10.3390\/v16111703"},{"key":"ref_3","unstructured":"CDC (2026, June 02). Global Human Cases with Avian Influenza A(H5N1), 1997\u20132026, Available online: https:\/\/www.cdc.gov\/bird-flu\/php\/surveillance\/chart-epi-curve-ah5n1.html."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"4637","DOI":"10.1038\/s41598-025-87831-w","article-title":"Evaluation of humoral immune response and milk antibody transfer in calves and lactating cows vaccinated with inactivated H5 avian influenza vaccine","volume":"15","author":"Abousenna","year":"2025","journal-title":"Sci. Rep."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1038\/s41541-025-01238-2","article-title":"Immunogenicity and safety of a rabies-based highly pathogenic influenza A virus H5 vaccine in cattle","volume":"10","author":"Paran","year":"2025","journal-title":"npj Vaccines"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Santos, J.J.S., Souza, C.K., Zanella, G.C., Goulart, D.B., Arruda, B., Boggiatto, P., Palmer, M.V., Snyder, C.A., Kristula, M.A., and Dickens, C. (2026). Evaluation of an H5 influenza virus mRNA-lipid nanoparticle (LNP) vaccine in lactating dairy cows. bioRxiv.","DOI":"10.64898\/2026.03.03.709308"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1038\/s41541-026-01460-6","article-title":"Dual-route H5N1 vaccination induces systemic and mucosal immunity in murine and bovine models","volume":"11","author":"Wiggins","year":"2026","journal-title":"npj Vaccines"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"nwaf262","DOI":"10.1093\/nsr\/nwaf262","article-title":"H5N1 virus invades the mammary glands of dairy cattle through \u2018mouth-to-teat\u2019 transmission","volume":"12","author":"Shi","year":"2025","journal-title":"Natl. Sci. Rev."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2514356","DOI":"10.1080\/21645515.2025.2514356","article-title":"Developing the next-generation of adenoviral vector vaccines","volume":"21","author":"Sampson","year":"2025","journal-title":"Hum. Vaccin. Immunother."},{"key":"ref_10","unstructured":"Curiel, D.T., and Parker, A.L. (2025). Chapter 21\u2014Adenovirus vectored veterinary vaccines. Adenoviral Vectors for Gene Therapy, Academic Press. [3rd ed.]."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"956","DOI":"10.1016\/S1473-3099(23)00068-3","article-title":"Safety and immunogenicity of a ChAdOx1 vaccine against Rift Valley fever in UK adults: An open-label, non-randomised, first-in-human phase 1 clinical trial","volume":"23","author":"Jenkin","year":"2023","journal-title":"Lancet Infect. Dis."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"20617","DOI":"10.1038\/srep20617","article-title":"Chimpanzee Adenovirus Vaccine Provides Multispecies Protection against Rift Valley Fever","volume":"6","author":"Warimwe","year":"2016","journal-title":"Sci. Rep."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"719","DOI":"10.1002\/bit.24342","article-title":"Preventing spontaneous genetic rearrangements in the transgene cassettes of adenovirus vectors","volume":"109","author":"Cottingham","year":"2012","journal-title":"Biotechnol. Bioeng."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Dicks, M.D., Spencer, A.J., Edwards, N.J., Wadell, G., Bojang, K., Gilbert, S.C., Hill, A.V., and Cottingham, M.G. (2012). A novel chimpanzee adenovirus vector with low human seroprevalence: Improved systems for vector derivation and comparative immunogenicity. PLoS ONE, 7.","DOI":"10.1371\/journal.pone.0040385"},{"key":"ref_15","unstructured":"WHO (2011). Manual for the laboratory diagnosis and virological surveillance of influenza. WHO Global Influenza Surveillance Network, World Health Organization."},{"key":"ref_16","first-page":"e54897","article-title":"Optimization of a Quantitative Micro-neutralization Assay","volume":"118","author":"Lin","year":"2016","journal-title":"J. Vis. Exp."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1083","DOI":"10.1586\/erv.10.103","article-title":"Generating humoral immune memory following infection or vaccination","volume":"9","author":"Randall","year":"2010","journal-title":"Expert Rev. Vaccines"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Jang, Y.H., and Seong, B.L. (2021). Immune Responses Elicited by Live Attenuated Influenza Vaccines as Correlates of Universal Protection against Influenza Viruses. Vaccines, 9.","DOI":"10.3390\/vaccines9040353"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"566","DOI":"10.1038\/s41385-020-0287-5","article-title":"Seasonal and pandemic influenza: 100 years of progress, still much to learn","volume":"13","author":"Dunning","year":"2020","journal-title":"Mucosal Immunol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"e0062125","DOI":"10.1128\/jvi.00621-25","article-title":"Dairy cattle herds mount a characteristic antibody response to highly pathogenic H5N1 avian influenza viruses","volume":"99","author":"Simmons","year":"2025","journal-title":"J. Virol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"110927","DOI":"10.1016\/j.virol.2026.110927","article-title":"H5N1 avian influenza in dairy cattle: Molecular adaptation, transmission mechanisms, and control strategies","volume":"621","author":"Ding","year":"2026","journal-title":"Virology"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1996","DOI":"10.1016\/j.bpj.2022.10.026","article-title":"Mechanistic dissection of antibody inhibition of influenza entry yields unexpected heterogeneity","volume":"122","author":"Sengar","year":"2023","journal-title":"Biophys. J."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"110970","DOI":"10.1016\/j.vetmic.2026.110970","article-title":"Evaluation of immune response in calves vaccinated with baculovirus vectored inactivated vaccine expressing 2.3.4.4b H5 protein of highly pathogenic Avian Influenza virus","volume":"316","author":"Lee","year":"2026","journal-title":"Vet. Microbiol."},{"key":"ref_24","first-page":"1721","article-title":"Persistence of Influenza H5N1 and H1N1 Viruses in Unpasteurized Milk on Milking Unit Surfaces","volume":"30","author":"Campbell","year":"2024","journal-title":"Emerg. Infect. Dis."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1366","DOI":"10.1038\/s41564-025-01998-6","article-title":"Dairy cows develop protective immunity against reinfection with bovine H5N1 influenza virus","volume":"10","author":"Facciuolo","year":"2025","journal-title":"Nat. Microbiol."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Rainard, P., Foucras, G., and Martins, R.P. (2022). Adaptive Cell-Mediated Immunity in the Mammary Gland of Dairy Ruminants. Front. Vet. Sci., 9.","DOI":"10.3389\/fvets.2022.854890"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"785","DOI":"10.1080\/14760584.2018.1516553","article-title":"Effector mechanisms of influenza-specific antibodies: Neutralization and beyond","volume":"17","author":"Sicca","year":"2018","journal-title":"Expert Rev. Vaccines"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1016\/j.coviro.2016.12.002","article-title":"Antibody-dependent cellular cytotoxicity and influenza virus","volume":"22","author":"Vanderven","year":"2017","journal-title":"Curr. Opin. Virol."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Ulfman, L.H., Leusen, J.H.W., Savelkoul, H.F.J., Warner, J.O., and van Neerven, R.J.J. (2018). Effects of Bovine Immunoglobulins on Immune Function, Allergy, and Infection. Front. Nutr., 5.","DOI":"10.3389\/fnut.2018.00052"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Hunagund, S., Golan, Y., Asiodu, I.V., Prahl, M., and Gaw, S.L. (2022). Effects of Vaccination Against Influenza, Pertussis, and COVID-19 on Human Milk Antibodies: Current Evidence and Implications for Health Equity. Front. Immunol., 13.","DOI":"10.3389\/fimmu.2022.910383"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1070","DOI":"10.1038\/s42003-026-09783-9","article-title":"Multimerization of secretory IgA enhances antiviral activity by aggregating influenza A virus particles","volume":"9","author":"Yamauchi","year":"2026","journal-title":"Commun. Biol."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Pyles, K., Darling, T.L., Huang, L.C., Guebre-Xabier, M., Hersey, M., Greene, A.M., Patel, N., Smith, G., and Boon, A.C.M. (2026). Intranasal and intramuscular H5-Matrix-M nanoparticle vaccines protects against highly pathogenic H5N1 influenza virus in mice. npj Vaccines.","DOI":"10.1038\/s41541-026-01523-8"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Rainard, P., Gilbert, F.B., and Germon, P. (2022). Immune defenses of the mammary gland epithelium of dairy ruminants. Front. Immunol., 13.","DOI":"10.3389\/fimmu.2022.1031785"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"188","DOI":"10.1038\/s41541-024-00989-8","article-title":"Aerosol immunization with influenza matrix, nucleoprotein, or both prevents lung disease in pig","volume":"9","author":"Vatzia","year":"2024","journal-title":"npj Vaccines"}],"container-title":["Vaccines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-393X\/14\/8\/691\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T04:15:51Z","timestamp":1786680951000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-393X\/14\/8\/691"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,12]]},"references-count":34,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["vaccines14080691"],"URL":"https:\/\/doi.org\/10.3390\/vaccines14080691","relation":{},"ISSN":["2076-393X"],"issn-type":[{"value":"2076-393X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,12]]}}}