This Evidence Snapshot is an updated rapid review of current knowledge about aerosol transmission of COVID-19. The original review was completed in August 2020 and this updated review in October 2020. The updated review found that the weight of evidence was that aerosol transmission of SARS-CoV-2 does occur. Five reviews found that the virus may spread as an aerosol. Experimental studies demonstrated aerosolisation of the virus with persistence from 90 minutes to 16 hours, and evidence for horizontal transmission was found for ranges from two to eight metres. Environmental sampling studies typically found viral RNA both in the air and on air vents. Eight out of ten investigations of outbreaks reviewed found that transmission occurred without close direct contact. Risk of transmission was thought to be associated with shared indoor space, closed air recirculation and singing. Eighteen articles were reviewed in the updated report in addition to the nineteen articles in the original report, for a total of thirty-seven articles.
Dawson G, Moore G, du Toit A, Gordon R, Thompson S, Taha H, Sharma S. Update: What is known about aerosol transmission of SARS-CoV-2?: an Evidence Snapshot brokered by the Sax Institute for the Australian Commission on Safety and Quality in Health Care, 2020.