Abstract
Staff working in units that were highly exposed to coronavirus disease 2019 were invited to participate in a 6-month study on the carriage and seroprevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The results from visits on Day 1 and Day 15 show that 41 cases of SARS-CoV-2 infection were confirmed by reverse transcriptase polymerase chain reaction and/or serology in 326 participants (overall infection rate 12.6%). The presence of comorbidities or symptoms at the time of sample collection was a risk factor for infection, but working as a physician/nurse was not a risk factor. Universal screening in high-risk units, irrespective of symptoms, allowed the identification of asymptomatic and potentially contagious infected workers, enabling them to self-isolate for 7 days.