Nosocomial COVID-19 Incidence and Secondary Attack Rates among Patients of Tertiary Care Center, Zurich, Switzerland

Abstract

Of 1,118 patients with COVID-19 at a university hospital in Switzerland during October 2020–June 2021, we found 83 (7.4%) had probable or definite healthcare-associated COVID-19. After in-hospital exposure, we estimated secondary attack rate at 23.3%. Transmission was associated with longer contact times and with lower cycle threshold values among index patients.

Keywords

• COVID-19
• SARS-COV-2
• coronavirus disease
• severe acute respiratory syndrome coronavirus 2
• zoonoses
• nosocomial infections