SARS-CoV-2 seroprevalence and asymptomatic viral carriage in healthcare workers: a cross-sectional study
Research output: Contribution to journal › Article › peer-review
Colleges, School and Institutes
- University of Southampton
- University Hospitals Birmingham NHS Foundation Trust
- College of Medical and Dental Sciences, The University of Birmingham
- Public Health England Midlands and East Region
OBJECTIVE: To determine the rates of asymptomatic viral carriage and seroprevalence of SARS-CoV-2 antibodies in healthcare workers.
DESIGN: A cross-sectional study of asymptomatic healthcare workers undertaken on 24/25 April 2020.
SETTING: University Hospitals Birmingham NHS Foundation Trust (UHBFT), UK.
PARTICIPANTS: 545 asymptomatic healthcare workers were recruited while at work. Participants were invited to participate via the UHBFT social media. Exclusion criteria included current symptoms consistent with COVID-19. No potential participants were excluded.
INTERVENTION: Participants volunteered a nasopharyngeal swab and a venous blood sample that were tested for SARS-CoV-2 RNA and anti-SARS-CoV-2 spike glycoprotein antibodies, respectively. Results were interpreted in the context of prior illnesses and the hospital departments in which participants worked.
MAIN OUTCOME MEASURE: Proportion of participants demonstrating infection and positive SARS-CoV-2 serology.
RESULTS: The point prevalence of SARS-CoV-2 viral carriage was 2.4% (n=13/545). The overall seroprevalence of SARS-CoV-2 antibodies was 24.4% (n=126/516). Participants who reported prior symptomatic illness had higher seroprevalence (37.5% vs 17.1%, χ2=21.1034, p<0.0001) and quantitatively greater antibody responses than those who had remained asymptomatic. Seroprevalence was greatest among those working in housekeeping (34.5%), acute medicine (33.3%) and general internal medicine (30.3%), with lower rates observed in participants working in intensive care (14.8%). BAME (Black, Asian and minority ethnic) ethnicity was associated with a significantly increased risk of seropositivity (OR: 1.92, 95% CI 1.14 to 3.23, p=0.01). Working on the intensive care unit was associated with a significantly lower risk of seropositivity compared with working in other areas of the hospital (OR: 0.28, 95% CI 0.09 to 0.78, p=0.02).
CONCLUSIONS AND RELEVANCE: We identify differences in the occupational risk of exposure to SARS-CoV-2 between hospital departments and confirm asymptomatic seroconversion occurs in healthcare workers. Further investigation of these observations is required to inform future infection control and occupational health practices.
|Number of pages||6|
|Early online date||11 Sep 2020|
|Publication status||Published - 16 Nov 2020|
- Adult, Antibodies, Viral/blood, Asymptomatic Diseases, COVID-19/diagnosis, Cross-Sectional Studies, Female, Health Personnel/statistics & numerical data, Humans, Male, Middle Aged, Pandemics, RNA, Viral/analysis, SARS-CoV-2/genetics, Seroepidemiologic Studies