{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T04:27:34Z","timestamp":1772252854155,"version":"3.50.1"},"reference-count":20,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2020,10,27]],"date-time":"2020-10-27T00:00:00Z","timestamp":1603756800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>We reviewed the association between seasonal influenza vaccination and the risk of SARS-CoV-2 infection or complicated illness or poor outcome (e.g., severe disease, need for hospitalization or ventilatory support, or death) among COVID-19 patients. None of the studies that were reviewed (n = 12) found a significant increase in the risk of infection or in the illness severity or lethality, and some reported significantly inverse associations. Our findings support measures aimed at raising influenza vaccination coverage in the coming months.<\/jats:p>","DOI":"10.3390\/ijerph17217870","type":"journal-article","created":{"date-parts":[[2020,10,27]],"date-time":"2020-10-27T09:22:45Z","timestamp":1603790565000},"page":"7870","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["The Association between Influenza Vaccination and the Risk of SARS-CoV-2 Infection, Severe Illness, and Death: A Systematic Review of the Literature"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2742-0297","authenticated-orcid":false,"given":"Marco","family":"Del Riccio","sequence":"first","affiliation":[{"name":"Postgraduate Medical School in Public Health, University of Florence, 50134 Florence, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3170-1857","authenticated-orcid":false,"given":"Chiara","family":"Lorini","sequence":"additional","affiliation":[{"name":"Department of Health Sciences, University of Florence, 50134 Florence, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5171-4308","authenticated-orcid":false,"given":"Guglielmo","family":"Bonaccorsi","sequence":"additional","affiliation":[{"name":"Department of Health Sciences, University of Florence, 50134 Florence, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John","family":"Paget","sequence":"additional","affiliation":[{"name":"Netherlands Institute for Health Services Research (Nivel), 3513 Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2262-1102","authenticated-orcid":false,"given":"Saverio","family":"Caini","sequence":"additional","affiliation":[{"name":"Molecular and Lifestyle Epidemiology Branch, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), 50139 Florence, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"108378","DOI":"10.1016\/j.mbs.2020.108378","article-title":"Modeling the impact of mass influenza vaccination and public health interventions on COVID-19 epidemics with limited detection capability","volume":"325","author":"Li","year":"2020","journal-title":"Math. 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