Effect of Influenza Vaccination on Risk of Coronavirus Disease 2019: A Prospective Cohort Study of 46 000 Healthcare Workers

Jonas Henrik Kristensen; Rasmus Bo Hasselbalch; Mia Pries-Heje; Pernille Brok Nielsen; Andreas Dehlbæk Knudsen; Kamille Fogh; Jakob Boesgaard Norsk; Aleksander Eiken; Ove Andersen; Thea Kølsen Fischer; Claus Antonio Juul Jensen; Christian Torp-Pedersen; Jørgen Rungby; Sisse Bolm Ditlev; Ida Hageman; Rasmus Møgelvang; Mikkel Gybel-Brask; Ram Benny Dessau; Erik Sørensen; Lene Harritshøj; Fredrik Folke; Maria Elizabeth Engel Møller; Thomas Benfield; Henrik Ullum; Charlotte Sværke Jørgensen; Sisse Rye Ostrowski; Susanne Dam Nielsen; Henning Bundgaard; Kasper Iversen

doi:10.1093/infdis/jiac001

Effect of Influenza Vaccination on Risk of Coronavirus Disease 2019: A Prospective Cohort Study of 46 000 Healthcare Workers

J Infect Dis. 2022 Aug 12;226(1):6-10. doi: 10.1093/infdis/jiac001.

Authors

Jonas Henrik Kristensen^{1

2

3}, Rasmus Bo Hasselbalch^{1

2

3}, Mia Pries-Heje^{4

3}, Pernille Brok Nielsen^{1

2

3}, Andreas Dehlbæk Knudsen^{4

5

3}, Kamille Fogh^{1

2

3}, Jakob Boesgaard Norsk^{1

2

3}, Aleksander Eiken^{6

3}, Ove Andersen^{7

3}, Thea Kølsen Fischer^{8

9}, Claus Antonio Juul Jensen^{10

3}, Christian Torp-Pedersen^{8

9}, Jørgen Rungby^{6

3}, Sisse Bolm Ditlev^{11

3}, Ida Hageman^{12

3}, Rasmus Møgelvang^{4

3}, Mikkel Gybel-Brask^{13

3}, Ram Benny Dessau^{14

15}, Erik Sørensen^{13

3}, Lene Harritshøj^{13

3}, Fredrik Folke^{1

16

3}, Maria Elizabeth Engel Møller¹⁷, Thomas Benfield^{17

3}, Henrik Ullum¹⁸, Charlotte Sværke Jørgensen¹⁸, Sisse Rye Ostrowski^{13

3}, Susanne Dam Nielsen^{5

3}, Henning Bundgaard^{4

3}, Kasper Iversen^{1

2

3}

Affiliations

¹ Department of Cardiology, Copenhagen University Hospital, Herlev and Gentofte, Borgmester Ib Juuls vej 1, Herlev, Denmark.
² Department of Emergency Medicine, Copenhagen University Hospital, Herlev and Gentofte, Borgmester Ib Juuls vej 1, Herlev, Denmark.
³ Department of Clinical Medicine, University of Copenhagen, Blegdamsvej 3B, Copenhagen, Denmark.
⁴ Department of Cardiology, Copenhagen University Hospital - Rigshospitalet, Blegdamsvej 9, Copenhagen, Denmark.
⁵ Department of Infectious Disease, Copenhagen University Hospital - Rigshospitalet, Blegdamsvej 9, Copenhagen, Denmark.
⁶ Department of Endocrinology and Copenhagen Center for Translational Research, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Bispebjerg Bakke 23, Copenhagen, Denmark.
⁷ Department of Emergency and Department of Clinical Research, Copenhagen University Hospital, Amager og Hvidovre, Kettegård Alle 30, Hvidovre, Denmark.
⁸ Department of Clinical Research, Copenhagen University Hospital - Nordsjællands Hospital, Dyrehavevej 29, Hillerød, Denmark.
⁹ Department of Public Health, University of Copenhagen, Blegdamsvej 3B, Copenhagen, Denmark.
¹⁰ Department of Clinical Biochemistry, Copenhagen University Hospital - Nordsjællands Hospital, Dyrehavevej 29, Hillerød, Denmark.
¹¹ Department of Pulmonary Medicine and Copenhagen Center for Translational Research, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Bispebjerg Bakke 23, Copenhagen, Denmark.
¹² Mental Health Services - The Capital Region of Denmark, Kristineberg 3, Copenhagen, Denmark.
¹³ Department of Clinical Immunology, Copenhagen University Hospital - Rigshospitalet, Blegdamsvej 9, Copenhagen, Denmark.
¹⁴ Department of Clinical Microbiology, Zealand University Hospital - Slagelse, Ingemannsvej 46, Slagelse, Denmark.
¹⁵ Institut for Regional Sundhedsforskning, University of Southern Denmark, J.B. Winsløws Vej 19, Odense, Denmark.
¹⁶ Copenhagen University Hospital - Copenhagen Emergency Medical Services, Telegrafvej 5A, Ballerup, Denmark.
¹⁷ Department of Infectious Disease, Copenhagen University Hospital - Amager and Hvidovre, Kettegaard Alle 30, Hvidovre, Denmark.
¹⁸ Statens Serum Institut, Artillerivej 5, Copenhagen, Denmark.

Abstract

Background: The purpose of this study was to assess whether influenza vaccination has an impact on the risk of coronavirus disease 2019 (COVID-19).

Methods: A cohort of 46 112 healthcare workers were tested for antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and filled in a survey on COVID-19 symptoms, hospitalization, and influenza vaccination.

Results: The risk ratio of hospitalization due to SARS-CoV-2 for influenza vaccinated compared with unvaccinated participants was 1.00 for the seasonal vaccination in 2019/2020 (confidence interval, .56-1.78, P = 1.00). Likewise, no clinical effect of influenza vaccination on development of antibodies against SARS-CoV-2 was found.

Conclusions: The present findings indicate that influenza vaccination does not affect the risk of SARS-CoV-2 infection or COVID-19.

Keywords: COVID-19; SARS-CoV-2; cohort study; healthcare workers; influenza vaccination.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

COVID-19* / prevention & control
Health Personnel
Humans
Influenza, Human* / epidemiology
Influenza, Human* / prevention & control
Prospective Studies
SARS-CoV-2
Vaccination