A team of scientists has called for more research on how sunlight is disrupted SARS-CoV-2 After realizing that there is a stark contrast between the latest theories and experimental results.
A mechanical engineer at the University of California, Santa Barbara Paolo Lozato Figues and colleagues noted that the virus was inactivated eight times faster in the experiments than the latest theoretical model predicted.
“The theory assumes that the inactivation works by infecting UVB with the virus’s RNA, thus damaging it,” explained Lozato Figgis.
But the paradox indicates that something more is happening than that, and finding out what is useful in managing the virus may be.
Ultraviolet light, or the ultraviolet part of the spectrum, is readily absorbed by certain nucleic acid bases in DNA and RNA, which can cause them to bind in ways that are difficult to repair.
But Not all UV light is the same. The longer ultraviolet light waves, called UVA, do not contain enough energy to cause problems. The mid-range UVB waves in sunlight are primarily responsible for killing microbes and putting our cells at risk of sun damage.
But this type of UV rays doesn’t usually come in contact with the Earth’s surface, thanks Ozone layer.
“UVC is great for hospitals,” She said Co-author and toxicologist at Oregon State University Julie McMurray. “But in other environments – for example, kitchens or subways – UV rays interact with particles to produce harmful ozone.”
In July 2020, An experimental study I tested the effects of UV light on SARS-CoV-2 in a saliva simulation. They recorded that the virus was inactivated when exposed to simulated sunlight for 10-20 minutes.
“Natural sunlight may be effective as a disinfectant for contaminated non-porous materials,” Wood and colleagues It concluded in the paper.
Luzzatto-Feigiz and the team compared these results with theory On how sunlight achieved this, which was published just a month later, he felt that mathematics was not feasible.
This study found that SARS-CoV-2 was three times more sensitive to UV rays in sunlight than influenza A, with 90 percent of the Corona VirusIts particles are inactivated after only half an hour of exposure to midday sun in summer.
In comparison, infectious particles in winter light can remain intact for several days.
Environmental calculations carried out by a separate team of researchers is over The virus RNA particles are exposed to photochemical damage directly by light rays.
This is achieved most strongly with shorter wavelengths of light, such as UVC and UVB. Since UVC does not reach the Earth’s surface, they based the environmental light exposure calculations on the UVB medium wave portion of the ultraviolet spectrum.
“The inhibition experimentally observed in simulating saliva is eight times faster than would be expected from theory,” Wrote Luzzatto-Feigiz and colleagues.
“So, scientists don’t yet know what’s going on,” Lozato Figues She said.
The researchers think it is possible that rather than directly affecting the RNA, the long wave Grapes It may interact with the particles in the test medium (simulated saliva) in a way that speeds up the inactivation of the virus.
Something similar has been seen In wastewater treatment Ultraviolet rays interact with other materials to form particles that harm viruses.
If UVA can be harnessed to fight SARS-CoV-2, then inexpensive, energy-efficient wavelength light sources may be useful in augmenting air purification systems with relatively low risks to human health.
“Our analysis indicates the need for additional experiments to separately test the effects of specific optical wavelengths and medium fitting,” Luzzatto-Fegiz. Concludes.
With the ability of this virus to It remains suspended in the air For extended periods of time, the safest way to avoid it in countries where it is rampant is still social distancing and wearing masks where the distancing cannot be. But it is good to know that sunlight can help us get outside during the warmer months.
Their analysis has been published in The Journal of Infectious Diseases.