{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T04:15:36Z","timestamp":1790828136361,"version":"4.1.0"},"update-to":[{"DOI":"10.1371\/journal.ppat.1009928","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2021,11,4]],"date-time":"2021-11-04T00:00:00Z","timestamp":1635984000000}}],"reference-count":44,"publisher":"Public Library of Science (PLoS)","issue":"10","license":[{"start":{"date-parts":[[2021,10,25]],"date-time":"2021-10-25T00:00:00Z","timestamp":1635120000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003246","name":"Nederlandse Organisatie voor Wetenschappelijk Onderzoek","doi-asserted-by":"publisher","award":["Spinoza Grant"],"award-info":[{"award-number":["Spinoza Grant"]}],"id":[{"id":"10.13039\/501100003246","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010663","name":"H2020 European Research Council","doi-asserted-by":"publisher","award":["833247"],"award-info":[{"award-number":["833247"]}],"id":[{"id":"10.13039\/100010663","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010663","name":"H2020 European Research Council","doi-asserted-by":"publisher","award":["948207"],"award-info":[{"award-number":["948207"]}],"id":[{"id":"10.13039\/100010663","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Radboud University Medical Centre","award":["Hypatia Grant"],"award-info":[{"award-number":["Hypatia Grant"]}]},{"DOI":"10.13039\/100010127","name":"J\u00fcrgen Manchot Foundation","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100010127","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["428917761"],"award-info":[{"award-number":["428917761"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Research Committee of the Heinrich Heine University Duesseldorf"}],"content-domain":{"domain":["www.plospathogens.org"],"crossmark-restriction":false},"short-container-title":["PLoS Pathog"],"abstract":"<jats:p>\n                    Non-specific protective effects of certain vaccines have been reported, and long-term boosting of innate immunity, termed\n                    <jats:italic>trained immunity<\/jats:italic>\n                    , has been proposed as one of the mechanisms mediating these effects. Several epidemiological studies suggested cross-protection between influenza vaccination and COVID-19. In a large academic Dutch hospital, we found that SARS-CoV-2 infection was less common among employees who had received a previous influenza vaccination: relative risk reductions of 37% and 49% were observed following influenza vaccination during the first and second COVID-19 waves, respectively. The quadrivalent inactivated influenza vaccine induced a trained immunity program that boosted innate immune responses against various viral stimuli and fine-tuned the anti-SARS-CoV-2 response, which may result in better protection against COVID-19. Influenza vaccination led to transcriptional reprogramming of monocytes and reduced systemic inflammation. These epidemiological and immunological data argue for potential benefits of influenza vaccination against COVID-19, and future randomized trials are warranted to test this possibility.\n                  <\/jats:p>","DOI":"10.1371\/journal.ppat.1009928","type":"journal-article","created":{"date-parts":[[2021,10,25]],"date-time":"2021-10-25T13:32:43Z","timestamp":1635168763000},"page":"e1009928","update-policy":"https:\/\/doi.org\/10.1371\/journal.ppat.corrections_policy","source":"Crossref","is-referenced-by-count":153,"title":["Induction of trained immunity by influenza vaccination - impact on COVID-19"],"prefix":"10.1371","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3171-3903","authenticated-orcid":true,"given":"Priya A.","family":"Debisarun","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2898-131X","authenticated-orcid":true,"given":"Katharina L.","family":"G\u00f6ssling","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7077-6216","authenticated-orcid":true,"given":"Ozlem","family":"Bulut","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8251-1909","authenticated-orcid":true,"given":"Gizem","family":"Kilic","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3636-2209","authenticated-orcid":true,"given":"Martijn","family":"Zoodsma","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3641-4470","authenticated-orcid":true,"given":"Zhaoli","family":"Liu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5163-1724","authenticated-orcid":true,"given":"Marina","family":"Oldenburg","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9657-8787","authenticated-orcid":true,"given":"Nadine","family":"R\u00fcchel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2911-9422","authenticated-orcid":true,"given":"Bowen","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1586-4672","authenticated-orcid":true,"given":"Cheng-Jian","family":"Xu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0118-8829","authenticated-orcid":true,"given":"Patrick","family":"Struycken","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5783-9013","authenticated-orcid":true,"given":"Valerie A. 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