SARS-CoV-2 transmits principally by air; contact and fomite transmission may also occur. Variants of concern are more transmissible than ancestral SARS-CoV-2. We found indications of possible increased aerosol and surface stability for early variants of concern, but not for the Delta and Omicron variants. Stability changes are unlikely to explain increased transmissibility.
Keywords: COVID-19; Omicron; SARS-CoV-2; United States; aerosol; coronavirus disease; environmental stability; respiratory infections; severe acute respiratory syndrome coronavirus 2; transmission; variants of concern; viruses; zoonoses.