April 16 - A disinfecting system that uses visible lights to kill deadly hospital 'superbugs' is being pioneered by scientists and engineers in the Scottish city of Glasgow. Researchers believe the High Intensity Narrow Spectrum Light (HINS-light) technology could greatly enhance the decontamination of hospitals and other clinical environments. Jim Drury has more.
When patients are admitted to hospital they expect to be treated in a sterile, safe environment. But sometimes, that's not possible...thanks to the proliferation of deadly hospital 'superbugs' like E-coli, MRSA, and C-difficile. These bacterial infections have developed a resistance to antibiotics...but now a group of Scottish engineers and scientists believe their new technology could help kill the bugs and save lives.. In trials they incorporated High Intensity Narrow Spectrum Light, HINS-light, for short, in the overhead bulbs of a Glasgow hospital. Microbiology Professor John Anderson, is heading the team from Glasgow's Strathclyde University. SOUNDBITE (English) PROFESSOR JOHN ANDERSON, MICROBIOLOGIST AT UNIVERSITY OF STRATHCLYDE, SAYING: "The HINS light uses a narrow band of violet light from the visible light spectrum. It's lethal to bacteria, but harmless to people, so this allows us to use it in hospitals in the presence of patients and staff. It gives a continuous disinfection of the air and contact surfaces in the room." Wavelengths in the HINS-light Environmental Decontamination System operate at a peak of 405 nanometres. SOUNDBITE (English) PROFESSOR JOHN ANDERSON, MICROBIOLOGIST AT UNIVERSITY OF STRATHCLYDE, SAYING: "This kills bacteria because they contain certain photosensitive molecules called porphyrins and when the light hits these porphyrin molecules they become excited, they interact with oxygen, and this produces reactive oxygen species which kills the bacteria. It's a bit like releasing bleach inside the bacterium, so very simple technology. Simply shine light on the bacteria and they self-destruct." Dr Michelle MacLean's lab work involves exposing superbugs to HINS light sources. SOUNDBITE (English) DR MICHELLE MACLEAN, MICROBIOLOGIST AT UNIVERSITY OF STRATHCLYDE, SAYING: "Now that the bacteria has been seeded onto the surface we now need to look at exposing the surface to the HINS light treatment." (MACLEAN WALKS OVER TO HINS LIGHT) "And over here we have one example of the HINS light sources that we use......then we expose the bacteria to a set intensity and from that we can work out the dose depending on how long we expose it for.....Half the plate was covered with foil and the other half was left exposed. This was exposed under this treatment system which we see here and we can see that after incubation the colonies of E.coli have grown on the top half of the plate, which was the area which was left uncovered, and the areas which was exposed to the HINS light there's complete clearance of the organism on the surface." Fitted alongside existing hospital ceiling lights, the HINS bulbs can be automated to come on in the morning and switch off at night, providing constant protection. The team says they complement existing cleaning methods which, although effective, can't be used continuously and are jeopardised by staff forgetting to follow procedures. Their tests showed a 60 percent reduction of bacterial bioburden. Patients with open wounds or weakened immune systems are most at risk from superbugs, which are resistant to antibiotics, and in extreme cases can kill. The team hopes the HINS system will be commercialised worldwide by the end of this year, lighting the way to a healthier hospital environment. Jim Drury, Reuters