{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T04:08:59Z","timestamp":1780632539938,"version":"3.54.1"},"reference-count":67,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,5,28]],"date-time":"2026-05-28T00:00:00Z","timestamp":1779926400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Seqirus Spain, S.L."}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Influenza is an acute viral respiratory infection that generates a substantial clinical and socioeconomic burden, especially among high-risk populations such as older adults. In Spain, influenza accounts for approximately \u20ac128 million in direct healthcare costs each season, with 80% of expenditures concentrated in individuals over 45 years of age. Vaccination remains the most effective intervention to prevent complications and reduce healthcare pressure. However, current coverage rates are consistently below international targets and continue to decline. In this context, there is an urgent need to strengthen vaccination uptake, especially among high-risk groups. Increasing vaccination uptake is essential to lessen the clinical, societal, and economic burden of influenza, since modest improvements in coverage have a significant impact on public health outcomes and economic resilience. In fact, previously published modeling analyses indicate that a 1% reduction in national vaccination coverage could result in over 6400 additional influenza cases and an additional economic burden of \u20ac1.54 million per season. Furthermore, increasing coverage to 75% in Spain could prevent approximately 180,300 additional cases\u2014equivalent to 20% of the total\u2014which would translate into potential savings of \u20ac43 million (\u20ac26 million in direct medical costs and \u20ac17 million in work absenteeism costs). This manuscript provides an overview of the influenza burden and vaccination landscape in Spain, focusing on clinical, societal, and economic implications of suboptimal coverage, as well as the current challenges and opportunities to improve uptake. Available evidence indicates that influenza vaccination reduces severe outcomes and healthcare burden, suggesting that mildly improving coverage in Spain could yield substantial health and economic benefits. Taken together, these findings support influenza vaccination as a public health priority and a relevant investment for health systems.<\/jats:p>","DOI":"10.3390\/vaccines14060482","type":"journal-article","created":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T11:25:31Z","timestamp":1780399531000},"page":"482","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Influenza Vaccination in Spain: Understanding the Impact of Suboptimal Coverage on Health, Society, and the Economy"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5062-5135","authenticated-orcid":false,"given":"Mar\u00eda \u00c1ngeles","family":"Onieva-Garc\u00eda","sequence":"first","affiliation":[{"name":"Preventive Medicine and Public Health Unit, Hospital Universitario Reina Sof\u00eda, 14004 Cordoba, Spain"},{"name":"Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain"},{"name":"Department of Medical and Surgical Sciences, University of Cordoba, 14002 Cordoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irene","family":"Rivero-Calle","sequence":"additional","affiliation":[{"name":"Translational Paediatrics and Infectious Diseases Section, Paediatrics Department, Hospital Cl\u00ednico Universitario de Santiago de Compostela, 15706 Santiago de Compostela, Spain"},{"name":"Genetics, Vaccines, and Infections Research Group (GENVIP), Healthcare Research Institute of Santiago de Compostela, University of Santiago de Compostela, 15706 Santiago de Compostela, Spain"},{"name":"CIBER of Respiratory Diseases (CIBERES), Instituto de Salud Carlos III, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1295-7101","authenticated-orcid":false,"given":"\u00c1ngel Gil de","family":"Miguel","sequence":"additional","affiliation":[{"name":"CIBER of Respiratory Diseases (CIBERES), Instituto de Salud Carlos III, 28029 Madrid, Spain"},{"name":"Preventative Medicine and Public Health Area, Universidad Rey Juan Carlos, 28922 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antoni","family":"Trilla","sequence":"additional","affiliation":[{"name":"Preventive Medicine and Epidemiology Unit, Hospital Clinic, 08036 Barcelona, Spain"},{"name":"School of Medicine and Health Sciences, University of Barcelona, 08036 Barcelona, Spain"},{"name":"ISGlobal Research Institute, 08003 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"P\u00e9rez-Rubio","sequence":"additional","affiliation":[{"name":"Complejo Asistencial de \u00c1vila, 05071 \u00c1vila, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Wu, A., Peng, Y., Du, X., Shu, Y., and Jiang, T. 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