{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,15]],"date-time":"2025-12-15T19:50:07Z","timestamp":1765828207407,"version":"3.48.0"},"reference-count":67,"publisher":"BMJ","issue":"9","license":[{"start":{"date-parts":[[2022,9,22]],"date-time":"2022-09-22T00:00:00Z","timestamp":1663804800000},"content-version":"unspecified","delay-in-days":21,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2022,9,4]]},"published-print":{"date-parts":[[2022,9]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>As clinical presentation and complications of both viruses overlap, it was hypothesised that influenza vaccination was associated with lower general practitioner (GP)-diagnosed COVID-19 rates and lower all-cause mortality rates.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Study design<\/jats:title>\n                    <jats:p>From a primary care population-based cohort in the Netherlands, GP-diagnosed COVID-19 (between 10 March and 22 November 2020) and all-cause mortality events (between 30 December 2019 and 22 November 2020) were recorded. 223\u2009580 persons were included, representing the influenza vaccination 2019 target group (all aged \u226560 years, and those &lt;60 years with a medical indication). Proportional hazards regression analyses evaluated associations between influenza vaccination in 2019 and two outcomes: GP-diagnosed COVID-19 and all-cause mortality. Covariables were sex, age, comorbidities and number of acute respiratory infection primary care consultations in 2019.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A slightly positive association (HR 1.15; 95% CI 1.08 to 1.22) was found between influenza vaccination in 2019 and GP-diagnosed COVID-19, after adjusting for covariables. A slightly protective effect for all-cause mortality rates (HR 0.90; 95% CI 0.83 to 0.97) was found for influenza vaccination, after adjusting for covariables. A subgroup analysis among GP-diagnosed COVID-19 cases showed no significant association between influenza vaccination in 2019 and all-cause mortality.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Our hypothesis of a possibly negative association between influenza vaccination in 2019 and GP-diagnosed COVID-19 was not confirmed as we found a slightly positive association. A slightly protective effect on all-cause mortality was found after influenza vaccination, possibly by a wider, overall protective effect on health. Future research designs should include test-confirmed COVID-19 cases and controls, adjustments for behavioural, socioeconomic and ethnic factors and validated cause-specific mortality cases.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2022-061727","type":"journal-article","created":{"date-parts":[[2022,9,22]],"date-time":"2022-09-22T12:09:52Z","timestamp":1663848592000},"page":"e061727","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":4,"title":["Impact of influenza vaccination on GP-diagnosed COVID-19 and all-cause mortality: a Dutch cohort study"],"prefix":"10.1136","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0211-3669","authenticated-orcid":false,"given":"Arjan","family":"van Laak","sequence":"first","affiliation":[{"name":"Department of General Practice, CAPHRI, Maastricht UMC+, Maastricht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruud","family":"Verhees","sequence":"additional","affiliation":[{"name":"Department of General Practice, CAPHRI, Maastricht UMC+, Maastricht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J Andr\u00e9","family":"Knottnerus","sequence":"additional","affiliation":[{"name":"Department of General Practice, CAPHRI, Maastricht UMC+, Maastricht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mari\u00ebtte","family":"Hooiveld","sequence":"additional","affiliation":[{"name":"General Practice Care, Otterstraat 118, Nivel, Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bjorn","family":"Winkens","sequence":"additional","affiliation":[{"name":"Department of Methodology and Statistics, CAPHRI, Maastricht UMC+, Maastricht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7411-8325","authenticated-orcid":false,"given":"Geert-Jan","family":"Dinant","sequence":"additional","affiliation":[{"name":"Department of General Practice, CAPHRI, Maastricht UMC+, Maastricht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2022,9,22]]},"reference":[{"key":"2025121511411478000_12.9.e061727.1","unstructured":"Cascella M , Rajnik M , Aleem A . 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