Ultraviolet light technology shows effectiveness in protecting older Australians from respiratory infections

Simple technology that harnesses ultraviolet light to zap airborne viruses has been shown to significantly lower the number of respiratory infections in aged care facilities, paving the way for smarter infection control.

Adapted by scientists from Flinders Health and Medical Research Institute (FHMRI) and SAHMRI, the technology is based on using germicidal ultraviolet (GUV) appliances which purify the air with UV-C light rays and deactivate harmful microorganisms like viruses and bacteria.

The new study, published in JAMA Internal Medicine, trialed commercially available GUV appliances in aged care facilities, finding they reduced rates of viral respiratory infections in vulnerable older Australians by more than 12%.

“Some of the key advantages of germicidal ultraviolet air-treatment appliances are that they are easily installed into existing facilities and cost-effective to use,” says lead author Dr. Andrew Shoubridge from Flinders University and SAHMRI’s Microbiome and Host Health Program.

“When used in conjunction with existing infection control measures, they could be transformative in reducing rates of seasonal respiratory viral infections and protecting residential aged care facilities against emerging pathogens.”

Senior author of the study, Professor Geraint Rogers, conceived this world-first trial and the transformative adaptation of this technology to reduce respiratory viral outbreaks in vulnerable older Australians.

“Outbreaks of viruses such as COVID-19 are absolutely devastating for older people, significantly increasing the risks of hospitalization and death,” says Professor Rogers. “Our study aimed to explore new ways in which to protect aged care residents from harmful outbreaks of viruses, including COVID 19, without disrupting their day-to-day activities. Based on our findings, it’s difficult to see why you wouldn’t install these appliances in aged care facilities.”

The trial tested commercially available LAF Technologies GUV appliances that are already used in a wide range of clinical and commercial settings, including hospitals.

The appliances can be mounted to ceilings or walls, fitted into ventilated AC systems, are harmless to people, and have already proven to reduce levels of airborne pathogens in laboratory and hospital settings.

The appliances were installed and tested in four aged care homes across metropolitan and rural South Australia in communal areas that were exposed to high volumes of people where the transmission of airborne viruses is usually greater.

“We designed a randomized clinical trial to compare the same environments with and without the appliances tracking infection rates over two years,” says Dr. Shoubridge. “While the appliances didn’t seem to lower infection rates during short study periods, they did help reduce overall numbers of respiratory infections by 12.2%, or roughly 0.3 fewer cases per week. This means GUV technology could make a noticeable difference in protecting people in aged care facilities, especially when we consider there are 250,000 Australians currently living in them,” he says.

Professor Rogers says that while older people are particularly vulnerable to acute respiratory diseases, this technology could be hugely significant in reducing the burden of viral infections in other contexts and in helping prepare for future pandemics.