{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T16:00:54Z","timestamp":1782316854245,"version":"3.54.5"},"reference-count":27,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,2,7]],"date-time":"2024-02-07T00:00:00Z","timestamp":1707264000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Programme of Prevention, Surveillance and Control of Transmissible Diseases (PREVICET)","award":["2017\/SGR 1342"],"award-info":[{"award-number":["2017\/SGR 1342"]}]},{"name":"Programme of Prevention, Surveillance and Control of Transmissible Diseases (PREVICET)","award":["2021\/SGR 00702"],"award-info":[{"award-number":["2021\/SGR 00702"]}]},{"name":"CIBER de Epidemiolog\u00eda y Salud P\u00fablica (CIBERESP)","award":["2017\/SGR 1342"],"award-info":[{"award-number":["2017\/SGR 1342"]}]},{"name":"CIBER de Epidemiolog\u00eda y Salud P\u00fablica (CIBERESP)","award":["2021\/SGR 00702"],"award-info":[{"award-number":["2021\/SGR 00702"]}]},{"name":"Instituto de Salud Carlos III, Madrid and the Catalan Agency for the Management of Grants for University Research","award":["2017\/SGR 1342"],"award-info":[{"award-number":["2017\/SGR 1342"]}]},{"name":"Instituto de Salud Carlos III, Madrid and the Catalan Agency for the Management of Grants for University Research","award":["2021\/SGR 00702"],"award-info":[{"award-number":["2021\/SGR 00702"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Introduction: Influenza vaccination may be effective in preventing influenza infection and may reduce the risk of influenza-associated pneumonia. The study aim was to evaluate the effect of influenza vaccination in preventing pneumonia when it failed to prevent influenza hospitalization. Methods: This was a case\u2013control study comparing hospitalized cases of influenza with and without pneumonia in patients aged \u226518 years in 16 hospitals in Catalonia over 10 influenza seasons (2010\u201311 to 2019\u201320). Data on sociodemographic, virological characteristics, comorbidities, vaccination history, and antiviral treatment were collected and analysed. The crude odds ratio (OR) and adjusted OR (aOR) with the corresponding 95% confidence interval (CI) values were calculated. Results: In total, 5080 patients hospitalized for severe influenza were included, 63.5% (3224\/5080) of whom had pneumonia\u2014mostly men (56.8%; 1830\/3224) and mostly in the \u226575 age group (39.3%; 1267\/3224)\u2014and of whom 14.0% died (451\/3224). Virus A and virus B accounted for 78.1% (2518\/3224) and 21.9% (705\/3224) of influenza types, respectively. Starting antiviral treatment \u226448 h after symptom onset (aOR = 0.69; 95%CI: 0.53\u20130.90) and a history of seasonal influenza vaccination (aOR = 0.85; 95%CI: 0.72\u20130.98) were protective factors in developing pneumonia. Conclusions: Adherence to seasonal influenza vaccination and starting antiviral treatment within 48 h of symptom onset can reduce pneumonia risk in severe influenza cases.<\/jats:p>","DOI":"10.3390\/vaccines12020173","type":"journal-article","created":{"date-parts":[[2024,2,7]],"date-time":"2024-02-07T11:03:14Z","timestamp":1707303794000},"page":"173","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Effectiveness of Influenza Vaccination and Early Antiviral Treatment in Reducing Pneumonia Risk in Severe Influenza Cases"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2896-7286","authenticated-orcid":false,"given":"Pere","family":"Godoy","sequence":"first","affiliation":[{"name":"Institut de Recerca Biom\u00e9dica de Lleida (IRBLleida), Universitat de Lleida, 25006 Lleida, Spain"},{"name":"CIBER Epidemiolog\u00eda y Salud P\u00fablica (CIBERESP), 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1353-5325","authenticated-orcid":false,"given":"N\u00faria","family":"Soldevila","sequence":"additional","affiliation":[{"name":"CIBER Epidemiolog\u00eda y Salud P\u00fablica (CIBERESP), 28029 Madrid, Spain"},{"name":"Departament de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana","family":"Mart\u00ednez","sequence":"additional","affiliation":[{"name":"CIBER Epidemiolog\u00eda y Salud P\u00fablica (CIBERESP), 28029 Madrid, Spain"},{"name":"Ag\u00e8ncia de Salut P\u00fablica de Catalunya, 08005 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sofia","family":"Godoy","sequence":"additional","affiliation":[{"name":"Institut de Recerca Biom\u00e9dica de Lleida (IRBLleida), Universitat de Lleida, 25006 Lleida, Spain"},{"name":"Institut Catal\u00e0 de la Salut, 08007 Lleida, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mireia","family":"Jan\u00e9","sequence":"additional","affiliation":[{"name":"CIBER Epidemiolog\u00eda y Salud P\u00fablica (CIBERESP), 28029 Madrid, Spain"},{"name":"Ag\u00e8ncia de Salut P\u00fablica de Catalunya, 08005 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0143-5295","authenticated-orcid":false,"given":"Nuria","family":"Torner","sequence":"additional","affiliation":[{"name":"CIBER Epidemiolog\u00eda y Salud P\u00fablica (CIBERESP), 28029 Madrid, Spain"},{"name":"Ag\u00e8ncia de Salut P\u00fablica de Catalunya, 08005 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lesly","family":"Acosta","sequence":"additional","affiliation":[{"name":"Ag\u00e8ncia de Salut P\u00fablica de Catalunya, 08005 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristina","family":"Rius","sequence":"additional","affiliation":[{"name":"CIBER Epidemiolog\u00eda y Salud P\u00fablica (CIBERESP), 28029 Madrid, Spain"},{"name":"Ag\u00e8ncia de Salut P\u00fablica de Barcelona, 08023 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0219-1907","authenticated-orcid":false,"given":"\u00c0ngela","family":"Dom\u00ednguez","sequence":"additional","affiliation":[{"name":"CIBER Epidemiolog\u00eda y Salud P\u00fablica (CIBERESP), 28029 Madrid, Spain"},{"name":"Departament de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"name":"The Surveillance of Hospitalized Cases of Severe Influenza in Catalonia Working Group","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1285","DOI":"10.1016\/S0140-6736(17)33293-2","article-title":"Estimates of global seasonal influenza-associated respiratory mortality: A modelling study","volume":"391","author":"Iuliano","year":"2018","journal-title":"Lancet"},{"key":"ref_2","unstructured":"World Health Organization (WHO) (2013). 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