Ultraviolet light can help prevent spread of Covid - in the right dose, new study finds

Scientists at Columbia University have found that a particular type of ultraviolet light could be used to prevent the spread of coronavirus indoors

This 2020 electron microscope image shows the spherical coronavirus particles in what was believed to be the first US case of Covid (AP)

A type of ultraviolet light can kill the Covid virus without causing any harm if the right dose is given, a new study has found.

Scientists at Columbia University have found that a particular type of ultraviolet light, Far-UVC light, could be used to prevent the spread of coronavirus indoors, where it is most likely to be transmitted.

Dental students at the university often use Far-UVC lamps to disinfect the air and, according to researchers, it kills 98% of indoor airborne microbes in around five minutes.

David Brenner, director of the Center for Radiological Research at Columbia, told CBS News that the technology - which is still being tested - could be applied on aeroplanes and schools, as well as hospitals.

He said: "Where are we transmitting Covid? Where are we transmitting influenza? It's almost entirely indoors because you have so much ventilation outdoors.

"I think what we have achieved with Far-UVC is the equivalent of stepping outside."

The lamps can be installed on ceilings and cost less than £200 each.

Dr Brenner added: "We know there are going to be new variants that haven’t reached us yet, and the nice thing about Far-UVC is it should be effective against every type of virus."

Scientists also say that a huge benefit of using ultraviolet light to combat Covid infection is that the virus cannot develop resistance to it.

Ultraviolet lamps are usually used to sterilise hospital rooms when people are not around but, in this case, the different wavelength means the right dose is safe to use.

Steven Erde, who works at the College of Dental Medicine at Columbia University, added: "This is a great opportunity to decrease that load so that when the patients are here, the providers are safer and other patients in the same facility are safer."