By Kasia Kaluzny
Each year in Canada, more than 200,000 patients catch a hospital-acquired infection, and 8,000 patients die as a result. Hospital-acquired infections, also called “nosocomial infections” or “health care-associated infections” (HAIs), are caused by germs such as bacteria, viruses, and fungi. These infections not only endanger the lives of patients, but they also burden health care facilities by increasing costs due to longer hospital stays, more diagnostic tests, more treatments, and isolation precautions. Proper cleaning and infection-control practices have come a long way in curbing this problem, but they require adequate time and resources. Now, new disinfection technologies are being developed that could help. CADTH recently took a look at some of them as part of its Horizon Scanning program:
Blue-violet light to disinfect rooms
A new ceiling light called Indigo-Clean gives off a blue-violet light at a wavelength that kills bacteria. The light fixture comes in various sizes and light intensities so that it can be used in different hospital spaces, including patient rooms, waiting rooms, bathrooms, and surgical suites. The lights have two modes: the first, “white disinfection,” is used while the room is occupied and provides ambient light, and the second, “indigo disinfection,” provides more disinfection power without the ambient light. It is safe for staff and patients to be in the room during both modes, but studies on comfort levels for the blue-violet light are underway. Although more research is needed to see if the lights actually reduce hospital-acquired infections, several studies show that the lights do reduce bacterial levels on surfaces, with greater reductions seen the longer the lights are used. One issue to consider is that decontamination with blue-violet light can take several hours, whereas it takes minutes with ultraviolet-C (UV-C) light. A quicker decontamination has the advantage of making rooms available for patients sooner. On the other hand, blue-violet light does not damage rubber or plastic, which UV-C light can do over time.
Killing germs with UV-C light
A new technology using UV-C light is the LightStrike PX-UV system, a portable device that can be set up in a hospital room after cleaning. It blasts the space with UV-C light for about five minutes at each location in the room (it has to be placed at different locations for full coverage). Several studies have shown that the LightStrike system is effective. There were 10 studies that examined its ability to reduce infections, with most showing promising results. The LightStrike system reduced the number of infections caused by Clostridium difficile, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant enterococci (VRE), some of the most problematic bacteria in hospitals. However, it’s difficult to know the true effect of the LightStrike system because other infection-prevention programs, such as hand washing audits, were often started around the same time the system was introduced.
Shining a light on mobile devices
Mobile devices, such as smartphones and tablets, are widely used in hospitals, but they can be covered in germs. A new disinfection machine already in use at three Canadian hospitals is the CleanSlate UV Sanitizer. This countertop machine uses UV-C light to destroy microorganisms on mobile devices. Health care workers, patients, and visitors can place their mobile device in the CleanSlate UV Sanitizer, close the lid, and wash their hands while their device is irradiated with UV-C light. After a disinfection cycle of 30 seconds, the lid opens automatically, and the mobile device is ready to be removed and used. Laboratory testing using a prototype found that the CleanSlate UV Sanitizer killed 99% of methicillin-resistant Staphylococcus aureus bacteria and C. difficile spores on pre-cleaned surfaces. More research is needed to see if using the CleanSlate UV Sanitizer will actually reduce hospital-acquired infections.
A salty solution?
Another way to reduce the spread of bacteria is to inhibit their ability to grow on frequently touched surfaces such as doorknobs, bed rails, toilet handles, and taps. A Canadian company called Outbreaker Solutions has started making coatings for these items out of 99 per cent compressed salt, which is known to have antimicrobial properties. The inventor of Outbreaker products was familiar with the ability of salt to slow bacterial growth from his work in the meat industry, and he partnered with University of Alberta researchers to bring this solution to the health care setting. Pilot evaluations of Outbreaker products are underway at several Alberta facilities, and the company expects to launch its first products in Canada in late 2017.
It may seem unlikely, but sharks are influencing how infections are prevented in hospitals. A micropatterned surface that mimics the natural texture and pattern of shark skin has been developed to interfere with the ability of bacteria to stick to its surface. Called Sharklet, it was discovered through research for the US Office of Naval Research and has been used for many years to prevent marine organisms attaching to submarines and ships. Now it’s been applied to the health care setting, with the hopes of reducing bacterial contamination. Laboratory studies show promising results, with reduced bacterial adhesion and growth on medical equipment and frequently touched surfaces covered with the Sharklet material. Studies are also underway to investigate Sharklet’s use in catheters and other medical devices. More research is needed to see how the material will affect rates of hospital-acquired infections.
These are just some of the many new technologies being developed to fight hospital-acquired infections. The Canadian Standards Association (CSA Group) has published a document to help with the evaluation of new materials and technologies for infection prevention and control. It provides several checklists to help with decision-making and explains the limitations that exist in current research.
For more information about the technologies covered here, read our latest Health Technology Update newsletter: cadth.ca/dv/health-technology-update-issue-19.
If you would like to learn more about CADTH, visit cadth.ca, follow us on Twitter @CADTH_ACMTS, or speak to a Liaison Officer in your region: cadth.ca/Liaison-Officers. To suggest a new or emerging health technology for CADTH to review, email us at HorizonScanning@cadth.ca.
Kasia Kaluzny is a Knowledge Mobilization Officer at CADTH and has a Master of Science degree in Microbiology.