Copper killed the superbug in 90 minutes

The University of Southampton team found the superbug was unable to survive on copper alloy surfaces for longer than 90 minutes.

MRSA can live for up to three days on surfaces such as stainless steel, Dr Jonathan Noyce and colleagues found.

They presented their findings at a recent meeting of the American Society for Microbiology in New Orleans.

MRSA, or Methicillin-resistant Staphylococcus aureus, is a growing problem for the NHS, with more than 7,000 cases occurring each year in England alone.

If you changed some of these surfaces to copper-based alloys these bacteria would be dead in 90 minutes

Researcher Dr Jonathan Noyce

People who are ill and are vulnerable to infection are at greatest risk of MRSA and can die if they become infected.

Scientists are continually looking for ways to fight the infection.

It has been known for some time that heavy metals such as copper are antimicrobial.

Other researchers have looked at whether different bacteria can survive on different metals, but nobody had looked at MRSA.

Dr Noyce and Professor Bill Keevil compared the survival rates of MRSA on stainless steel, the most commonly used metal in hospitals, and on selected copper alloys.

They found that at room temperature MRSA persisted for up to 72 hours on stainless steel, meaning it had the potential to spread to other surfaces it came into contact with.

In comparison, yellow brass rendered the bacteria completely harmless after four and a half hours.

Copper alloys were the best, destroying MRSA in as little as an hour and a half.

Copper knobs

Dr Noyce and colleagues believe switching hospital work surfaces and door handles from stainless steel to copper could help combat MRSA.

Dr Noyce said: "MRSA infections in hospitals are pretty rife and out of control. The main mechanism of transfer of MRSA is though cross-contamination on work surfaces and contact surfaces such as door handles and push plates.

MRSA infections in hospitals are pretty rife and out of control.

Dr Jonathan Noyce

But he said it would be relatively expensive and suggested the best place to start might be critical care areas where patients are at greatest risk if they become infected.

He said it would still be important to include other infection control measures, such as good hand hygiene.

Professor Keevil said the results were less impressive at lower temperatures, which might have implications for areas like cold storage areas and refrigerators.

"Hygiene is particularly imperative in those environments," he said.

Professor Curtis Gemmell, director of the Scottish MRSA Reference Laboratory, said the theory behind the research was good but questioned whether it would be feasible to change surfaces to copper alloys.

"I don't know how it would stand up to wear and tear...and it's a reactive metal and may discolour and become unsightly.

"Bugs tend to go into places that you can't easily clean. Things like door handles and surfaces should be easily cleaned," he said.