SARS-CoV-2 Variants Would Rapidly Inactivate With Sunlight

According to a study published in The Journal of Infectious Diseases on April 2, 2021, 'These results suggest that transmissibility differences among SARS-CoV-2 lineages are likely, not due to differences in aerosol stability.'

The stability in aerosols of four SARS-CoV-2 isolates, including one from lineage B.1.1.7, is similar when compared across multiple environmental conditions. These researchers focused on an isolate of B.1.1.7 as well as three other Coronavirus strains (hCoV-19/France/IDF0372/2020, hCoV-19/USA/NY-PV08449, and hCoV-19/USA/WA-1/2020), testing the effects of light, humidity, and temperature on aerosols from a simulated respiratory tract lining fluid in a rotating drum chamber.

No difference was identified in the absence of sunlight at 20°C or 40°C, but a small significant difference was seen in some aerosols when exposed to sunlight at 20°C and 20% relative humidity.

"There were no differences in the decay constants between isolates in darkness at either 20°C or 40°C, with a mean time for a 90% loss of viral infectivity across all dark conditions of 6.2 hours."

Despite the small difference, these data suggest that the SARS-CoV-2 lineages represented by all four isolates would be rapidly inactivated by natural sunlight in real-world scenarios.