You can kill Covid with a flick of a switch, study shows

As the world continues to race toward a vaccine for Covid-19, new Israeli research shows that the humble light bulb could become a major player in the fight against the pandemic.

Researchers have discovered that coronavirus can be killed quickly, efficiently and cheaply using ultraviolet light-emitting diodes, or UV LED lights.

In a study recently published in the Journal of Photochemistry and Photobiology B: Biology researchers found the optimal wavelength for killing the coronavirus is 267 nanometers.

They also discovered that a wavelength of 286 nanometers is almost as efficient, requiring less than half a minute to destroy more than 99.9 percent of the coronaviruses - good news considering that 286 nm LED bulbs are much cheaper and more readily available, and could be installed in air conditioning and water systems.

Tel Aviv University's Prof. Hadas Mamane, who led the study, believes that the technology will soon be available for use.

"The entire world is currently looking for effective solutions to disinfect the coronavirus," she said. "The problem is that in order to disinfect a bus, train, sports hall or plane by chemical spraying, you need physical manpower, and in order for the spraying to be effective, you have to give the chemical time to act on the surface.

"The disinfection systems based on LED bulbs, however, can be installed in the ventilation system and air conditioner, for example, and sterilize the air sucked in and then emitted into the room."

Mamane explains that it is quite simple to kill the coronavirus using LED bulbs that radiate ultraviolet light.

"But no less important, we killed the viruses using cheaper and more readily available LED bulbs, which consume little energy and do not contain mercury like regular bulbs. Our research has commercial and societal implications, given the possibility of using such LED bulbs in all areas of our lives, safely and quickly."

Ultraviolet radiation is a common method for killing viruses and bacteria. Ultraviolet disinfecting bulbs can be found, for example, in home water purifiers.

Earlier this year, scientists determined that applying ultraviolet light on the inside of ventilation systems in indoor spaces can quickly and efficiently deactivate both airborne and surface-deposited Covid-19.

Despite the exciting discovery, this is not the time to string purple lights all over your home.

"Of course, as always when it comes to ultraviolet radiation, it is important to make it clear to people that it is dangerous to try to use this method to disinfect surfaces inside homes," Mamane warned.

"You need to know how to design these systems and how to work with them so that you are not directly exposed to the light."