As it turns out, President Trump might have been on to something last spring when he rambled during a press conference about the possibility that “sunlight” could be leveraged to destroy the virus.
Research recently published by a team of academics at UC Santa Barbara found that the coronavirus is “inactivated” by sunlight as much as 8x faster than “current theoretical modelling” had anticipated. UC Santa Barbara assistant professor of mechanical engineering Paolo Luzzatto-Fegiz analyzed studies exploring the effects of different forms of UV radiation on SARS-CoV-2, and found a significant discrepancy, according to RT.
As with all electromagnetic radiation, UV falls on a spectrum. Longer-wave UVA reacts differently with parts of DNA and RNA than mid-range UV waves that are found in sunlight. These shorter-range waves can kill microbes and cause sunburns in humans. While short-wave UV radiation has been shown to deactivate viruses like SARS-CoV-2,light from this end of the spectrum is often deflected away from humanity by the Earth’s ozone lawyer.
But an analysis of various studies of how different types of UV light interacts with SARS-CoV-2 found that COVID should disintegrate even more quickly when exposed to summer sunlight, which features more short-wave radiation, one reason risk of contracting the virus outdoors during the summer is much, much lower than being indoors in the winter.
In practice, the team found that “inactivation” of virus particles rendered in simulated saliva was more than 8x faster than scientists believed in conditions similar to summer sunlight.
A July 2020 experimental study tested the power of UV light on SARS-CoV-2, contained in simulated saliva, and found the virus was inactivated in under 20 minutes.
However, a theory published a month later suggested sunlight could achieve the same effect, which didn’t quite add up. This second study concluded that SARS-CoV-2 was three times more sensitive to UV radiation in sunlight than the influenza A virus.
The vast majority of coronavirus particles were rendered inactive within 30 minutes of exposure to midday summer sunlight, whereas the virus could survive for days under winter sunlight.
“The experimentally observed inactivation in simulated saliva is over eight times faster than would have been expected from the theory,” Luzzatto-Feigiz and his team said. “So, scientists don’t yet know what’s going on.”
The UC Santa Barbara team hypothesized that the process that destroys the virus is similar to a process seen in wastewater treatment plants.
The team suspects that, as the UVC doesn’t reach the Earth, instead of directly attacking the RNA, the long-wave UVA in sunlight interacts with molecules in the virus’ environment, such as saliva, which speeds up the inactivation, in a process witnessed previously in wastewater treatment.
Their research suggests that an air filtration system equipped with certain types of UVA-emitters could dramatically reduce the spread of viral particles indoors.
For some reason, all this research about the effects of sunlight on the virus has been ignored by governments like the Spanish government, which recently ordered masks to be worn outdoors, something the country’s hospitality industry fears will destroy more already-embattled businesses while contributing nothing to the public safety effort. But maybe soon that will change.