Specific risk factors for SARS-CoV-2 transmission among health care workers in a university hospital

Abstract

Aim: To investigate the specific risk factors for novel coronavirus (SARS-CoV-2) transmission among health care workers (HCWs) in a tertiary care university hospital.

Methods: Upper respiratory samples of HCWs were tested for SARS-CoV-2 by reverse transcriptase polymerase chain reaction. A case-control study was conducted to explore the possible risk factors that lead to SARS-CoV-2 transmission to HCWs.

Results: Of 703 HCWs screened between March 20 and May 20, 2020, 50 (7.1%) were found to be positive for SARS-CoV-2. The positivity rates for SARS-CoV-2 among physicians, nurses, cleaning personnel, and the other occupations were 6.3%, 8.0%, 9.1%, and 2.6%, respectively. The infection rate was 8.3% among HCWs who worked in COVID-19 units and 3.4% among those who did not work in coronavirus disease 2019 (COVID-19) units (RR = 2.449, confidence interval = 1.062-5.649, P= .027). The presence of a SARS-CoV-2 positive person in the household (P = .016), inappropriate use of personnel protective equipment while caring for patients with COVID-19 infection (P = .003), staying in the same personnel break room as an HCW without a medical mask for more than 15 minutes (P = .000), consuming food within 1 m of an HCW (P = .003), and failure to keep a safe social distance from an HCW (P = .003) were statistically significant risk factors for infection.

Conclusion: HCWs have a high risk for SARS-CoV-2 transmission while providing care to COVID-19 patients. Transmission may also occur in nonmedical areas of the hospital while speaking or eating. Periodic screening of HCWs for SARS-CoV-2 may enable early detection and isolation of infected HCWs.

Keywords: COVID-19; Case-control; Health care worker; Infection control.