Source: Columbia University Irving Medical Center
Summary: According to a new study, continuous low doses of far ultraviolet C (far-UVC) light can kill airborne flu viruses without harming human tissues.
Scientists have known for decades that broad-spectrum UVC light, which has a wavelength of between 200 – 400 nm, is highly effective at killing bacteria and viruses by destroying the molecular bonds that hold their DNA together. This conventional UV light is routinely used to decontaminate surgical equipment. But conventional germicidal UV light is also a human health hazard and can lead to skin cancer and cataracts, which prevents its use in public spaces. Researchers from the Columbia University Irving Medical Center found that continuous low doses of far ultraviolet C (far-UVC) light can kill airborne flu viruses without harming human tissues. The findings suggest that use of overhead far-UVC light in hospitals, doctors’ offices, schools, airports, airplanes, and other public spaces could provide a powerful check on seasonal influenza epidemics, as well as influenza pandemics. The study findings were published in the journal Scientific Reports.
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. But because viruses and bacteria are much smaller than human cells, far-UVC light can reach their DNA and kill them. Influenza virus spreads from person to person mainly through fine liquid droplets, or aerosols, that become airborne when people with a flu cough, sneeze or talk. This new study was designed to test if far-UVC light could efficiently kill aerosolized influenza virus in the air, in a setting similar to a public space. In the study, aerosolized H1N1 virus – a common strain of flu virus was released into a test chamber and exposed to very low doses of 222 nm far-UVC light. The far-UVC light efficiently inactivated the flu viruses, with about the same efficiency as conventional germicidal UV light.
Prof. David J. Brenner said, “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.”
More Information: David Welch et al, “Far-UVC light: A new tool to control the spread of airborne-mediated microbial diseases”, Scientific Reports (2018). DOI: 10.1038/s41598-018-21058-w