Dynamic of SARS-CoV-2 RT-PCR positivity and seroprevalence among high-risk health care workers and hospital staff.

Staff members from Covid-19 highly exposed units were invited to participate in a six month study of SARS-CoV-2 carriage and seroprevalence. The results of Day 1 and Day 15 visits show that 41 SARS-CoV-2 infections were confirmed by RT-PCR and/or serology in 326 participants (overall infection rate=12.6%). Having co-morbidity or symptoms at the time of collection was a risk factor for infection but not working as a physician/nurse. This universal screening in high-risk units irrespective of symptoms allowed asymptomatic and potentially contagious infected workers to be self-isolated during 7 days.