First wave of COVID-19 in hospital staff members of a tertiary care hospital in the greater Paris area: surveillance and risk factors study.

Abstract Introduction Better understanding how hospital staff members (HSMs), including HCWs, were contaminated by SARS-CoV-2 during the first wave can help refining the control measures, in the context of the current second wave in Europe. Methods From March 5th to May 10th 2020, the infectious diseases unit at Raymond-Poincare teaching Hospital opened a weekday consultation dedicated to HSMs for a PCR testing. While in the waiting room, HSMs were offered to complete a questionnaire on their potential risk exposure to SARS-CoV-2. Results Of the 200 HSMs screened, 70 were positive. Ninety-nine HSMs (including 86 HCWs) completed the questionnaire of whom 28 cases positive. In the multivariable analysis among healthcare workers, age ≥ 44 years-old (aOR = 5.2, 95%CI [1.4-22.5]), not using a facemask systematically when caring for a patient (aOR = 13.9, 95%CI [1.8-293.0]), were significantly associated with SARS-CoV-2 infection. Conversely, working in a ward dedicated to COVID-19 patients (aOR = 0.7, 95%CI [0.2-3.2]) was not significantly associated with SARS-CoV-2 infection. Regarding community related exposures occurring in and outside the hospital among the HSMs, participation to meetings inside the hospital without wearing a facemask (aOR = 21.3, 95%CI [4.5-143.9]) and participation to private gathering (aOR = 10, 95%CI [1.3-91.0]) were significantly associated with SARS-CoV-2 infection. Conclusions Our results support the effectiveness of barrier precautions, underline that in-hospital contaminations not related to patient care may occur, and that part of the contaminations may be related to exposures in the community. Better protecting HCWs against COVID-19 and thereby ensuring workforces is crucial to fight the current second wave of the epidemic.