Utilisation of SARS-CoV-2 rapid antigen assays in screening asymptomatic hospital visitors: mitigating the risk in low-incidence settings.

Retrospective contact tracing enabled by the usage of automated-visitor-management-systems and digital-contact-tracing together with rapid-antigen-detection (RAD) for SARS-CoV-2 amongst visitors staying ≥30 minutes identified COVID-19 cases amongst <0.01% (6/72605) of hospital visitors to a large hospital campus over an 8-week study period. The potential for nosocomial transmission of SARS-CoV-2 from hospital visitors was very low, and can be further mitigated by universal masking amongst staff and visitors.