UV light can kill airborne flu virus, study finds

Feb. 9 (UPI) — Experiments prove low doses of far ultraviolet C light, or far-UVC light, can wipe out airborne flu virus without harming humans.

Researchers at the Columbia University Irving Medical Center suggest far-UVC lamps should be installed in hospitals, doctors offices, schools, airports and other public places.

Currently, ultraviolet light is used to decontaminate surgical equipment, but the light isn’t safe for human exposure.

“Unfortunately, conventional germicidal UV light… can lead to skin cancer and cataracts, which prevents its use in public spaces,” David J. Brenner, a professor of radiation biophysics and director of the Center for Radiological Research at CUIMC, said in a news release.

Traditional UV lamps feature a broad spectrum of light wavelengths between 200 to 400 nanometers. Such wavelengths can penetrate human skin and damage cells.

“Far-UVC light has a very limited range and cannot penetrate through the outer dead-cell layer of human skin or the tear layer in the eye, so it’s not a human health hazard,” Brenner said. “But because viruses and bacteria are much smaller than human cells, far-UVC light can reach their DNA and kill them.”

In previous studies, Brenner and his colleagues showed far-UVC light can kill MRSA bacteria without harming human and mice tissue. MRSA bacteria lives primarily on surfaces and is spread through direct contact.

In the new study, published this week in the journal Scientific Reports, scientists wanted to find out if far-UVC light could combat the flu, which is spread through tiny airborne droplets. When infected parties cough or sneeze, the virus becomes aerosolized.

In test chambers, scientists found 222 nanometer far-UVC light was just as effective as broad spectrum UV light at killing and deactivating the aerosolized influenza virus.

“If our results are confirmed in other settings, it follows that the use of overhead low-level far-UVC light in public locations would be a safe and efficient method for limiting the transmission and spread of airborne-mediated microbial diseases, such as influenza and tuberculosis,” said Brenner.