SARS-CoV-2 seroprevalence in high-risk health care workers in a Belgian general hospital: evolution from the first wave to the second

ABSTRACT

Health care workers (HCWs) are at the frontline for combatting the ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. To describe recent or past infections, the novel development of serological assays enabled the assessment of the immune response developed in coronavirus disease (COVID-19). Here, we investigate SARS-CoV-2 seroprevalence in high-risk HCWs in a Belgian general hospital after both the first and the second waves. Three different immunoassays were used to determine immune response to SARS-CoV-2 in volunteer HCWs who worked in at least one COVID-19-dedicated ward [emergency department, intensive care unit (ICU) and internal medicine department] in our institution from 8 May 2020 to 19 May 2020 (n = 267) and from 18 January 2021 to 8 February 2021 (n = 189). Risk factors for seropositivity were also assessed using a questionnaire filled out by all participants. We report a steep increase in seroprevalence after the second wave and report a higher seropositivity in HCWs than in the general population. Furthermore, we show that ICU personnel and especially nurses exhibit a proportionally lower SARS-CoV-2 seroprevalence. This study documents the rapid increase in SARS-CoV-2 seroprevalence in highly exposed HCWs in a context of high viral circulation prior to vaccination campaigns. Most importantly, it suggests a lower occupational risk in ICU and illustrates the role of diagnostic labeling and use of personal protective equipment during the COVID-19 pandemic.

KEYWORDS:

• SARS-CoV-2
• COVID-19
• health care workers
• seroprevalence
• intensive care unit

Acknowledgments

The authors would like to thank all participants who volunteered for this study and are grateful for the courage and dedication of the whole personnel at the Clinique Notre-Dame de Grâce during the COVID-19 pandemic. We also want to thank our colleagues clinical pathologists, the laboratory personnel and more especially the phlebotomists who collected the questionnaires and performed venipunctures and the chemistry technicians who performed the analyses in this study. Finally, we thank Emilie Catry (Clinique Notre-Dame de Grâce, Gosselies, Belgium) and Julien Favresse (Clinique Saint-Luc, Bouge, Belgium) for their insights on the redaction of our paper.

Disclosure statement

The authors report no declarations of interest.

Additional information

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.