Study population and setting
The study consisted of ten experimental conditions evaluating aerosols and surface stability (on plastic, stainless steel, copper and cardboard) of SARS-CoV-2 and SARS-CoV-1. Each experimental condition was replicated three times.
Summary of Main Findings
Aerosolized SARS-CoV-2 was viable throughout the 3-hour experiment, though infectious titers decreased as the volume of air increased. SARS-CoV-2 was detected at 72 hours on plastic and stainless steel surfaces. On cardboard and copper surfaces, no viable SARS-CoV-2 was detected at 24 hours and 4 hours respectively. Across tested surfaces, the longest half-lives of SARS-CoV-2 were 5.6 hours on stainless steel and 6.8 hours on plastic. Overall, the stability of SARS-CoV-2 and SARS-CoV-1 were similar.
The study tested a range of experimental conditions and identified 1) duration of any viable virus, 2) predicted decay of virus, and 3) the half-life of viable virus. This was one of the first studies to examine aerosol and surface stability and has important implications on public health mitigation efforts.
Given the limited estimates (each estimate based on three replications) and large standard errors for reporting the stability on cardboard, results should be reviewed with caution.
The results highlight the potential for aerosol and fomite transmission, given that the virus can remain viable and infectious in aerosols for hours and on surfaces for up to days. These are important considerations that should inform mitigation and containment strategies.