SARS-CoV-2 antibody seroprevalence in NHS healthcare workers in a large double-sited UK hospital.

We determined the seroprevalence of SARS-CoV-2 antibodies in NHS healthcare workers (HCWs) in a cross-sectional study from a large general hospital located in a double-sited rural and semi-rural area. The sample size of 3,119 HCWs (mean age 43±13) consisted of 75.2% women, 61.1% White individuals and predominantly (62.4%) asymptomatic individuals. Seroprevalence of SARS-CoV-2 antibodies was 19.7%. Determinants of seropositivity were preceding symptomatic infection and non-White ethnicity. Regardless of staff role or sex, multivariate regression analysis revealed that non-White HCWs were three times (odds ratio [OR] 3.12, 95% confidence interval [CI] 2.53-3.86, P<0.001) more likely to have antibodies than White staff, and seven times (OR 7.10, 95% CI 5.72-8.87, P<0.001) more likely if there was a history of preceding symptoms. We report relatively high rates of seropositivity in all NHS healthcare workers. Non-White symptomatic HCWs were significantly more likely to be seropositive than their colleagues, independent of age, sex or staff role.