Scientists Aim UVC Light to Stop Spread of SARS-CoV-2 Indoors

Experts in the fields of virology, immunology, aerosols, architecture, and physics surveyed the possible methods to prevent SARS-CoV-2 propagation in indoor spaces. Based on the survey results, they recommend the use of UVC light as a short-term, easily deployable, affordable way to limit virus spread in the current pandemic.

The study, published in ACS Nano, was undertaken by scientists at the Institute of Photonic Sciences (ICFO), the University of the Basque Country, Technion - Israel Institute of Technology, and the University of Southampton. It discusses currently available UVC sources, such as fluorescent lamps, microcavity plasmas, and LEDs, as well as alternative, nontraditional paths to UVC light generation. The researchers believe that by irradiating this type of light inside the ventilation systems of buildings and in shared indoor spaces while not in use, it could be possible to quickly and efficiently deactivate airborne and surface-deposited SARS-CoV-2 viruses.

Pathways of viral infection in everyday life shown in a simplified scheme (top) and illustrated by pictorial descriptions of exposure to virus in everyday activities (bottom). Placement of UVC light sources at ventilation systems and rooms not in use, without direct optical paths to humans, help reduce virus propagation. Courtesy of Nacho Gaubert.

The researchers also investigate the cost to deploy UVC technology globally. They propose that a global capital investment of a few billion dollars in UVC sources could protect about 10⁹indoor workers worldwide.

In shared indoor spaces such as offices and schools, in addition to airborne transmission, elements with small surface areas such as elevator buttons, door handles, and handrails are frequently used and can mediate transmission of the virus. The researchers propose that UVC light, in addition to reducing spread of the virus, could meet the requirements of rapid, widespread, economically viable deployment, and that its implementation is limited only by current production capacities.

The research was published in ACS Nano (www.doi.org/10.1021/acsnano.0c04596).