Cleaning with UV light can cut hospital superbug spread

Using a combination of chemicals and UV light to clean hospital rooms can cut transmission of four major superbugs, a new study has found.
Healthcare facilities continue to battle drug-resistant organisms such as methicillin-resistant Staphylococcus aureus (MRSA) that loiter on surfaces even after patient rooms have been cleaned and can cause new, sometimes-deadly infections.
The new study from Duke University School of Medicine has found that using a combination of chemicals and UV light to clean patient rooms cut transmission of four major superbugs by a cumulative 30 per cent among a specific group of patients - those who stay overnight in a room where someone with a known positive culture or infection of a drug-resistant organism had previously been treated.

This group of patients represented about five per cent of more than 600,000 patients across the study hospitals.
The randomised trial was conducted at nine hospitals in the US from 2012 to 2014, including three Duke University Health System hospitals, a Veterans Affairs hospital, and several smaller community healthcare centres.
The trial studied how three cleaning methods affected the transmission of four drug-resistant pathogens - MRSA, vancomycin-resistant enterococci (VRE), C difficile and Acinetobacter.

"Some of these germs are hardy and can live on the environment long enough that even after a patient with the organism has left the room and it has been cleaned, the next patient in the room could potentially be exposed," said lead investigator Deverick J Anderson from Duke Medicine.

"Several groups have demonstrated that enhanced cleaning strategies such as using portable UV machines can kill these germs, but this is the first well controlled study that shows these techniques can make meaningful difference in patient outcomes," Anderson said.
The standard approach for room cleaning involves the use of a quaternary ammonium disinfectant, or "quat."
Participating hospitals used three methods for killing the germs - irradiating the room with UV after using a quat, replacing the quat with bleach, and replacing the quat with bleach and irradiating the room with UV light.
The researchers found that the most effective strategy was to proceed with standard disinfection quats, followed by a 30 to 50 minute cycle with a portable UV irradiating machine.

"The staff would open drawers, open doors to the bathroom, roll the machine into the centre of the room," Anderson said.
"UV light works through reflective properties, killing organisms even in the shadows if there is space for light to reflect. The light disrupts the DNA of these germs and kills them," he said.
In the specific subgroup of patients who were studied, the method resulted in an almost one-third cumulative reduction in acquiring any of the four superbugs or developing infections in the following three months, the researchers found.