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. 2022 Jan 5:jiac001. doi: 10.1093/infdis/jiac001

Effect of influenza vaccination on risk of COVID-19 – A prospective cohort study of 46,000 health care workers

Jonas Henrik Kristensen 1,2,16,, Rasmus Bo Hasselbalch 1,2,16, Mia Pries-Heje 3,16, Pernille Brok Nielsen 1,2,16, Andreas Dehlbæk Knudsen 3,4,16, Kamille Fogh 1,2,16, Jakob Boesgaard Norsk 1,2,16, Aleksander Eiken 8,16, Ove Andersen 5,16, Thea Kølsen Fischer 6,17, Claus Antonio Juul Jensen 7,16, Christian Torp-Pedersen 6,17, Jørgen Rungby 8,16, Sisse Bolm Ditlev 13,16, Ida Hageman 9,16, Rasmus Møgelvang 3,16, Mikkel Gybel-Brask 12,16, Ram Benny Dessau 15,18, Erik Sørensen 12,16, Lene Harritshøj 12,16, Fredrik Folke 1,10,16, Maria Elizabeth Engel Møller 11, Thomas Benfield 11,16, Henrik Ullum 14, Charlotte Sværke Jørgensen 14, Sisse Rye Ostrowski 12,16, Susanne Dam Nielsen 4,16, Henning Bundgaard 3,16,2, Kasper Iversen 1,2,16,2
PMCID: PMC8755365  PMID: 34989811

Abstract

The purpose of this study was to assess if influenza vaccination has an impact on the risk of COVID-19. A cohort of 46,112 health care workers were tested for antibodies against SARS-CoV-2 and filled in a survey on COVID-19 symptoms, hospitalization, and influenza vaccination. The RR of hospitalization due to SARS-CoV-2 for influenza vaccinated compared with unvaccinated participants was 1.00 for the seasonal vaccination in 2019/2020 (CI 0.56-1.78, p=1.00). Likewise, no clinical effect of influenza vaccination on development of antibodies against SARS-CoV-2 was found. The present findings indicate that influenza vaccination does not affect the risk of SARS-CoV-2 infection or COVID-19.

Keywords: COVID-19, health care workers, SARS-CoV-2, influenza vaccination, cohort study, hospitalization, seroprevalence

Supplementary Material

jiac001_suppl_Supplementary_Appendix

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Supplementary Materials

jiac001_suppl_Supplementary_Appendix

Articles from The Journal of Infectious Diseases are provided here courtesy of Oxford University Press

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