{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T08:50:05Z","timestamp":1791967805386,"version":"4.3.4"},"reference-count":50,"publisher":"Wiley","issue":"9","license":[{"start":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T00:00:00Z","timestamp":1788393600000},"content-version":"vor","delay-in-days":2,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"},{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100003030","name":"Ag\u00e8ncia de Gesti\u00f3 d'Ajuts Universitaris i de Recerca","doi-asserted-by":"publisher","award":["2017\/SGR 1342"],"award-info":[{"award-number":["2017\/SGR 1342"]}],"id":[{"id":"10.13039\/501100003030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003030","name":"Ag\u00e8ncia de Gesti\u00f3 d'Ajuts Universitaris i de Recerca","doi-asserted-by":"publisher","award":["2021 SGR 00702"],"award-info":[{"award-number":["2021 SGR 00702"]}],"id":[{"id":"10.13039\/501100003030","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Influenza Resp Viruses"],"published-print":{"date-parts":[[2026,9]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Seasonal influenza, especially in persons with underlying medical conditions, is a substantial global burden. Influenza vaccination effectiveness (VE) varies annually, requiring continuous evaluation due to evolving viruses and vaccination coverages. Our aim was to investigate influenza VE in preventing hospitalization for confirmed influenza among people aged 15\u201364\u2009years with underlying medical conditions.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a multicentre case\u2013control study across 17 Spanish hospitals in hospitalized patients aged 15\u201364\u2009years with underlying medical conditions in three influenza seasons. Influenza VE was estimated using two types of controls: test\u2010negative controls and non\u2010acute respiratory infection controls. Data on demographics, underlying medical conditions, vaccination status and clinical outcomes were collected. Adjusted VE was analysed using multivariable logistic regression models.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Recruited were 1220 hospitalized adults with underlying medical conditions, of whom 25.2% were vaccinated. VE varied by season, age group, and virus subtype. Statistically significant protection was observed for all seasons jointly against influenza A(H3N2) subtype, whereas VE estimates for specific seasons and subtypes were not significant.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>These findings underscore the importance of continuous VE monitoring and tailored vaccination strategies to protect adults with underlying medical conditions and highlight low seasonal influenza vaccination coverage in this population. Influenza seasonal vaccination should be improved in people aged 15\u201364\u2009years with underlying medical conditions.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1111\/irv.70304","type":"journal-article","created":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T06:53:37Z","timestamp":1788504817000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Influenza Vaccination Effectiveness in Preventing Hospitalization of Adults With Underlying Medical Conditions: A Multicentre Case\u2013Control Study"],"prefix":"10.1111","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0794-9238","authenticated-orcid":false,"given":"Diana","family":"Toledo","sequence":"first","affiliation":[{"name":"Departament de Medicina Universitat de Barcelona  Barcelona Spain"},{"name":"CIBER en Epidemiolog\u00eda y Salud P\u00fablica\u2010CIBERESP  Madrid 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