The use of UV light is not, in any way, a viable treatment for people infected with SARS-CoV-2. However, due to its powerful sterilization abilities, this technology does have great potential for managing the COVID-19 pandemic in other ways.
UVC can kill germs and is an alternative to chemical disinfection. UVC can be used to sterilize objects, water, surfaces and materials – whether it’s to clean your phone, a hospital floor, or an entire bus in China.
The technology needed to generate UVC is not new and there is no reason to suggest this technology could not be implemented cost-effectively. Several companies have developed a variety of UV lamp systems, machines and even robots capable of sterilizing a range of surfaces.
Devices that emit UVC should be calibrated to ensure optimal microbial killing power and are more effective when placed close to the surface or object being treated. When turned off, UVC emission is stopped instantly.
As per the World Health Organization’s advice, direct UVC exposure should not be used to disinfect any areas of the skin. Studies are under way to identify particular UVCs that are safe for human cells and still worthwhile as germicides.
Far-UVC (wavelengths between 207-222 nanometers) is promising as it can’t cross physiological barriers, such as the dead outer layer of our skin, or the eye’s outer (tear film) layer.
Our knowledge of what constitutes “suitable” UVC emission is growing. This includes knowledge of the proper germicidal UVC wavelength that can be applied to surfaces, the amount of light that reaches the surface, and the exposure time needed to completely sterilize viral particles.
Research from 2002 confirmed UVC light inactivated SARS (severe acute respiratory syndrome) after six minutes of exposure.
A more recent study has shown UVC-based disinfection is helpful for stopping the SARS-CoV-2 virus from replicating. However, this is depended on how much of the virus was present and how much UVC exposure it received. A specific study on the efficiency of UVC to inactivate and inhibit the virus at low, medium and high concentrations, indicates a rather high UVC dosage for highest viral concentrations.
Another study looking at a different type of coronavirus (SARS-CoV-1) provided further evidence of the utility of UVC disinfection; and UV technology may be an option to filling gaps in the supply of personal protective equipment such as masks.
That said, as the pandemic continues, the deployment of UVC sanitizing technology across sectors could greatly contribute to our awareness of the risks presented by microbial pathogens.
The safe implementation of UVC-based measures could undoubtedly enhance public health and even biosecurity. Beyond the novel coronavirus, this arsenal has great potential to prevent costly impacts of future pandemics, too.
