High level of protection against COVID-19 after two doses of BNT162b2 vaccine in the working age population – first results from a cohort study in Southern Sweden

Abstract

Background

Vaccine effectiveness against COVID-19 needs to be assessed in diverse real-world population settings.

Methods

A cohort study of 805,741 residents in Skåne county, Southern Sweden, aged 18–64 years, of whom 26,587 received at least one dose of the BNT162b2 vaccine. Incidence rates of COVID-19 were estimated in sex- and age-adjusted analysis and stratified in two-week periods with substantial community spread of the disease.

Results

The estimated vaccine effectiveness in preventing infection ≥7 days after second dose was 86% (95% CI 72–94%) but only 42% (95% CI 14–63%) ≥14 days after a single dose. No difference in vaccine effectiveness was observed between females and males. Having a prior positive test was associated with 91% (95% CI 85–94%) effectiveness against new infection among the unvaccinated.

Conclusion

A satisfactory effectiveness of BNT162b2 after the second dose was suggested, but with possibly substantially lower effect before the second dose.

Keywords:

• SARS-CoV2
• COVID-19 vaccines
• COVID-19 testing
• vaccine effectiveness

Acknowledgments

Cecilia Åkesson-Kotsaris, Paul Söderholm and Helena Hallefjord, Clinical Studies Sweden, for excellence in bringing the data infrastructure in place. Susann Ullén, Clinical Studies Sweden, for statistical advice.

Ethics and permissions

Ethical approval was obtained from the Swedish Ethical Review Authority (2021-00059).

Author contributions

All authors conceived and designed the study, analysed and interpreted the results. UM, JB and MM acquired data, JB and MM conducted the statistical analyses. JB, FK, and MI drafted the manuscript. All authors critically revised the manuscript and approved the final version for submission. FK supervised the study and is the guarantor.

Disclosure statement

FK has on one occasion in 2019 held a lecture on vaccines for general practitioners sponsored by Sanofi Pasteur. All other authors declare no conflicts of interest, no support or financial relationship with any organisation or other activities with any influence on the submitted work.

Additional information

Funding

This study was supported by an internal grant for thematic collaboration initiatives at Lund University held by JB, and by Swedish Research Council [VR; grant number 2019-00198]. FK is supported by grants from the Swedish Research Council and Governmental Funds for Clinical Research (ALF). The funders played no role in the design of the study, data collection or analysis, decision to publish, or preparation of the manuscript.