Airborne Infections in Hospitals
As a wise man once said ‘I can’t go to hospital – that’s where all the sick people are!’ This makes light of a real problem facing the healthcare industry, though. HAIs (Hospital Acquired Infections or Healthcare Associated Infections) are dramatically on the rise. An estimated 1 in 10 patients of UK hospitals come down with one of these highly communicable bugs. Most of those affected are patients with weakened immune systems, suffering from respiratory infections due to coming in contact with airborne pathogens. As more and more infections become resistant or immune to even the most powerful antibiotics, this is a recipe for disaster.
Recent advances in the study of how these pathogens move through buildings have pointed out an interesting possible culprit: unhygienic ductwork. ‘Bio aerosols’ – the fine mist of sputum that fills the air after an infected patient coughs – fill not only their room but work their way through the air circulation systems. Soon everyone in the hospital has become exposed, and those whose immune systems have been compromised are at great risk of becoming infected.
So what can be done?
Scientists have discovered that the pathogens that travel through the air in this way, (MRSA, tuberculosis, SARS, avian flu and many others) are especially vulnerable to a narrow band of ultraviolet light. UV-C radiation at or near 245nm kills the pathogens in the bio aerosols, rendering them harmless. UV treatment even destroys infectious fungus spores like those of Aspergillus fumigatus.
But don’t hospitals filter their air?
Yes, they do! And air filtration is extremely important. It does stop the majority of pathogens and bio aerosols from circulating freely to find new victims. However, research suggests that the smallest viruses are much too tiny to be caught by even the finest filters available – at least at any reasonable level of economy.
Worse, the very filters which catch the pathogens can become host to moulds and fungi that can begin to reproduce rapidly in duct conditions, causing more harm.
What about positive-pressure systems?
Keeping the rooms of patients with weakened immune systems at a slightly higher pressure than those around them prevents most pathogens from entering the room, yes. However, these systems are expensive, difficult to control, and impractical when care givers must regularly enter or leave the room. Unless a full isolation system with an airlock is used, pressurisation cannot really keep pathogens out. There is also the issue of pathogens from the patients in the positive-pressure rooms being constantly blown out into the rest of the hospital.
UV-C Airstream disinfection
One answer to all these drawbacks is to add ultraviolet air purification systems to the existing filtration, positive pressure and other air quality procedures already employed. These systems are suitable for hospitals, office buildings and public spaces of all kinds. UV-C radiation is blocked by the ductwork itself and can cause no harm to people, even if the system is only inches from them. Those small viral particles and fungal spores that filtration systems pass through are especially vulnerable to the light, and can be killed just downstream of the filter. Both the air going into and out of positive pressure systems or isolation wards can be cleansed using UV-C systems, keeping everyone nearby safer from infection.
The key is choosing the right air hygiene systems for your building. When you consider upgrading your filtration systems, ask about the practicality of including ultraviolet infection control devices. They cost a lot less than you might think, and could save many lives.
At Ductbusters we offer a wide range of services to help improve the quality of indoor air within your establishment.
For more information please call 0800 085 0403
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