Given the difficulty of developing drugs to fight viral infections, researchers have been working on different approaches to containing the spread of dangerous infections for many years.
One of the latest findings is that far-UVC light could effectively kill the strains of viruses which cause the flu without inflicting any damage to human tissue.
Even though broad-spectrum UV radiation (which has a wavelength of 200 to 400 nanometres) has been used to disinfect surgical equipment for decades, it’s never been used in humans due to its potential for causing cancer and cataracts.
Far-UVC light, on the other hand, “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”, said lead author on the new study David J. Brenner from Columbia University, USA.
In contrast to human tissue, viruses and bacteria are much smaller and can therefore be reached by the far-UVC spectrum, causing damage to the molecular bonds that hold their DNA together, and killing them in the process.
Far-UVC radiation was also proven to be effective at eliminating MRSA – the methicillin-resistant Staphylococcus aureus gram-positive bacterium, a well-known cause of surgical wound infections – without harming either mouse or human skin.
To test their hypothesis, the researchers aerosolised the H1N1 virus (a common strain of the flu virus) and released it into a test chamber, which was then exposed to very low doses of 222 nanometre far-UVC radiation.
Results were promising – the far-UVC light inactivated the virus with about the same efficiency as conventional germicidal UV light.
“If our results are confirmed in other settings, it follows that the use of overhead low-level far-UVC light in public locations wold be a safe and efficient method for limiting the transmission and spread of airborne-mediated microbial diseases, such as influenza and tuberculosis,” said Brenner.
Currently, the price for one such lamp is a bit less than $1,000, which would almost certainly go down with the advent of mass production.
“And unlike flu vaccines, far-UVC is likely to be effective against all airborne microbes, even newly emerging strains,” Brenner added.