Healthcare-associated infections (HAIs) represent a major public health challenge worldwide, with approximately seven out of 100 patients in acute care hospitals in high-income countries and 15 in low- and middle-income countries acquiring at least one such infection during their hospital stay.
This comes from data from the World Health Organization, which further suggests that on average one in ten affected patients dies from HAI.
There are around 165,000 healthcare-associated infections (HAIs)1 in Australian healthcare facilities every year, making it the most common complication among patients in hospital.
Given the increasing burden of HAIs and antimicrobial resistance, efforts are being made at global, national and regional levels to improve infection prevention and control in hospitals and healthcare facilities.
Limitations of the traditional approach
At this year’s ESCMID Global Congress – an annual congress that brings together experts and specialists in the fields of clinical microbiology and infectious diseases – in Barcelona, Spain (April 27-30), Dr. Curtis Donskey from the Louis Stokes Cleveland VA Medical Center in Cleveland, Ohio, USA, will discuss new ultraviolet light air disinfection technology that could help protect against infections in healthcare settings.
The airborne transmission of diseases such as COVID-19 and tuberculosis in public spaces has highlighted the need for improved technologies to limit their spread. Environmental pollution also plays a key role in the spread of health-related infections with pathogens such as: Methicillin-resistant Staphylococcus aureus (MRSA) and Clostridioides difficile can remain on surfaces and contribute to the spread of infection.
“Compounding the problem and a major limitation of traditional cleaning and disinfection strategies is that disinfected surfaces quickly become re-contaminated between manual cleaning operations,” Donskey said.
Ultraviolet light technologies
“Daily cleaning of patient rooms is likely not enough to reduce exposure to infectious pathogens, and manual cleaning of complicated surfaces, equipment and equipment makes thorough cleaning difficult. These limitations have led to the development of technologies that enable continuous decontamination of occupied spaces between manual cleaning operations. The Holy Grail is a technology that is effective against surface and airborne pathogens and is automated, safe and cost-effective.”
One of the most promising candidates is ultraviolet light technology. “It has been known since the 1940s that ultraviolet light can kill bacteria and inactivate viruses in the air so that they are no longer infectious,” Donskey said.
“Traditional UV light is widely used in hospitals and prisons, but can damage skin and eyes and therefore should only be used when a room is empty. Because recontamination of spaces and surfaces occurs so quickly, the goal was to continually decontaminate spaces where people are present.”
Far ultraviolet light
Far-UV-C has a shorter wavelength (222 nm) than traditional germicidal UVC light (254 nm) and cannot penetrate or damage skin, eyes or tissue. Studies have shown that far UVC light can quickly and efficiently kill the SARS-CoV-2 virus, other human coronaviruses, influenza and drug-resistant bacteria.2 And because ultraviolet light kills microbes, viruses and bacteria, they cannot develop resistance, as is the case with vaccines and drug treatments. Additional testing in real indoor environments has shown that UV-C radiation reduces infectious airborne viruses by over 99% – much more than is generally achieved with typical air filtration and ventilation.3
Radiation of this far-flung UVC radiation into an empty room could decontaminate the air and surfaces in healthcare settings, and because the wavelength of this UV light is shorter than traditional UV light, researchers say it cannot penetrate our skin, eyes or penetrate or damage tissue.
“Several studies suggest that distant UV-C light may be safe for use near people at current legal limits. However, further studies are needed to confirm the safety of these radiations in clinical settings and with longer-term follow-up before this is the case.” “It is likely that they will be used routinely in staffed healthcare facilities,” Donskey warned.
“It is also important that we evaluate ozone concentrations, as UV-C technologies have the potential to generate modest amounts of ozone.” Based on currently available information, the U.S. Centers for Disease Control and Prevention explains that in the short term, UV radiation in all space is best viewed as a new and emerging technology.
Nevertheless, far-UV-C (222 nm) has emerged as a leading continuous decontamination technology, with several commercial technologies currently being marketed. Companies marketing far UV-C devices include Ushio (Care222 Filtered Far UV-C Excimer Lamp Module), Sterilray (GermBuster Channel), Lit Thinking (Visium), and Far UV Technologies.
Intermittent delivery
“Some early adopters have started using these technologies in healthcare,” Donskey said.
“For example, in 2020, a dental practice in Ohio installed far-UV-C lamps in five patient treatment rooms and operated the technology for thousands of hours without any reports of adverse effects. Collaborating with such early adopters could be useful to inform the long-term safety of far UV-C.
“A novel approach that could accelerate earlier implementation of far-UV-C in clinical settings would be intermittent rather than continuous administration. Such an approach would only provide distant UV-C when a room is empty and turn off when people are present. We are currently evaluating this intermittent approach to decontaminate equipment rooms, bathrooms, sinks and patient rooms. “We expect that with this approach, hospitals will be more willing to consider using the technology in clinical settings while additional safety data is generated,” he said.
1. Mitchell BG, Shaban RZ, MacBeth D, Wood CJ, Russo PL. The burden of healthcare-associated infections in Australian hospitals: a systematic review of the literature. Infection, illness and health. 2017 Sep 1;22(3):117-28.
2. Far-UVC light (222nm) efficiently and safely inactivates airborne human coronaviruses | Scientific Reports (nature.com); Far-UVC Light: A New Tool to Control the Spread of Airborne Microbial Diseases | Scientific reports (nature.com)
3. 222nm far-UVC light significantly reduces the amount of infectious airborne viruses in an occupied space | Scientific reports (nature.com)