During the study, researchers used state-of-the-art fluorescent microscopy to show copper eradicating MRSA spores within minutes; a finding that is expected to pave the way for the introduction of copper fixtures and fittings in medical environments, where across Europe MRSA kills more than 7,000 people a year – the same number as die in road traffic accidents.
We know that bugs can survive for weeks or months on stainless steel, but on copper they die off much more quickly
To test the theory, 10 million MRSA cells were introduced onto a 1cm2 piece of copper and an identical sample of stainless steel. This number is around 10,000 times higher than that typically encountered on fittings such as hospital door handles. A dye was then used, which showed live bacteria as green dots, displayed on a plasma screen.
After just two to three minutes, the stainless steel sample showed no major changes, while on the copper MRSA cells were beginning to die off. After six minutes, few cells remained on the copper sample, with still no significant changes on the stainless steel surface. After 10 minutes all cells had disappeared on the copper.
Changing common touch surfaces in hospitals to copper can help to break the chain of infection, leading to a more hygienic environment, which must have a positive impact on the wellbeing of patients, even in the face of antibiotic-resistant bacteria
Professor Bill Keevil, director of environmental healthcare at the university, and leader of the experiment, said: “We know that 80% of MRSA bugs are spread by touch. We also know that one contact will contaminate another seven surfaces, so what those surfaces are made of can make a difference. We know that bugs can survive for weeks or months on stainless steel, but on copper they die off much more quickly.”
The copper works by shutting down the physiology and biochemistry of the germs. Alloys such as brass are also effective and have recently been approved as anti-microbial surfaces by a US government agency.
Professor Keevil said: “As more resistant bacteria emerge, we are running out of drugs to treat the infections they cause, so we need to do everything practicable to prevent their spread. Copper is a powerful antimicrobial, which quickly and continuously reduces the number of bacteria on its surface. We have demonstrated it here in the lab and it has also been shown to be effective in busy clinical environments as part of a set of infection control procedures.
As more resistant bacteria emerge, we are running out of drugs to treat the infections they cause, so we need to do everything practicable to prevent their spread
“Changing common touch surfaces in hospitals to copper can help to break the chain of infection, leading to a more hygienic environment, which must have a positive impact on the wellbeing of patients, even in the face of antibiotic-resistant bacteria.”
The findings follow an earlier study at Selly Oak Hospital in Birmingham, during which all touch points such as door handles and sink taps were changed to copper. As a result the existence of germs was reduced by around 90%.
Trial leader, Professor Tom Elliott of the University Hospital Birmingham NHS Foundation Trust, said: “We have shown that copper has an effect for months. It is an exciting and unexpected finding.”
