Prevalence of SARS-COV-2 antibodies in the Thomayer University Hospital staff after the first wave of COVID-19.

Objectives: To map the prevalence of SARS-CoV-2 antibodies in the staff of the Thomayer University Hospital in Prague following the first wave of COVID-19. The main reason was the large number of COVID-19 patients admitted to the Thomayer University Hospital with confirmed SARS-CoV-2 infection.

Material And Methods: A volunteer study based on a questionnaire survey and determination of total antibodies (ECLIA, Roche) and individual classes of immunoglobulins (ELISA IgG and IgA, Euroimmun).

Results: The study involved 808 employees, 2/3 of whom were from clinical departments. Fifteen participants, predominantly nurses (n = 12), tested ECLIA positive for antibodies against SARS-CoV-2 and ELISA positive or borderline positive for IgG antibodies. Positive or borderline IgA antibodies were recorded in 12 subjects. Most of the positive study participants (n = 13) contracted the SARS-CoV-2 virus at the workplace after repeated contact with positive patients. Most subjects infected (n = 12) had a more severe course but did not require hospitalization. We detected only one asymptomatic antibody-positive person.

Conclusions: After the first wave of COVID-19, SARS-CoV-2 antibodies were only demonstrated in 1.9% of the Thomayer University Hospital employees tested. In clinical departments, the positivity rate was 2.3%, and in non-clinical departments, it was only 0.5%. The low prevalence of antibodies points to the low number of infected hospital staff and a very good level of compliance with all public health and epidemiological measures.