Sonshine can a Achilleshak of SARS-CoV-2. It has been known for some time that the coronavirus that causes COVID-19 is rapidly destroyed on a surface immersed in simulated sunlight, but a team of scientists now claims that the virus is even more susceptible to ultraviolet radiation than it is. previously realized.
In July 2020 an important study found that simulated sunlight rapidly inactivates SARS-CoV-2 on surfaces. According to their estimates, 90 percent of the SARS-CoV-2 virus was inactivated every 6.8 minutes in simulated saliva when exposed to simulated sunlight representing a clear summer day at sea level. The following month, another study produced a theoretical model describing the solar activation of SARS-CoV-2.
However, according to a team of researchers from UC Santa Barbara, Oregon State University, the University of Manchester and the ETH Zurich, there is some inconsistency between these results. in the Yourrnal of infectious diseases. They explain that laboratory experiments show that sunlight inactivates, which is several times faster than theory predicts. In fact, viruses were inactivated more than eight times faster in the experiments than the theory predicted.
To explain this gap, they argue that we need to look beyond Ultraviolet B (UVB), the higher energy ultraviolet light associated with skin burning, and to pay more attention to Ultraviolet A (UVA), the lower energy component of sunlight associated with the skin. aging.
“The theory assumes that inactivation works by allowing UV-B to hit the RNA of the virus and damage it,” Paolo Luzzatto-Fegiz, lead author of the Department of Mechanical Engineering at the University of Santa Barbara, in a statement.
“People do not consider UV-A to have much of an effect, but it may interact with some of the molecules in the medium,” Luzzatto-Fegiz added.
All this is now just the suspicion. The researchers did not do any modeling or experiments for themselves, but merely emphasized the peculiarities. difference between the data and the theory.
“Scientists therefore do not yet know what’s going on,” Luzzatto-Fegiz added; “Our analysis points to the need for additional experiments to test the effects of specific light wavelengths and medium composition separately.”
If they make money, it could be promising news. Some hospitals and other high-risk environments disinfect their air uses the power of UVC, which has even higher energy than UVB. But, this wavelength is largely absorbed by the earth’s ozone layer and does not reach the surface, which means that it must be created artificially.
“UV-C is ideal for hospitals,” adds co-author Julie McMurry. “But in other environments – for example kitchens or metros – UVC will communicate with the particles to produce harmful ozone.”
On the other hand, UVA is safe and easy to generate cheap LED light bulbs that are many times more powerful than natural sunlight. If UVA is actually the missing piece of the puzzle, it can be easily implemented in air filtration systems and disinfection methods to slow the spread of COVID-19 in high-risk spaces.