Hospital trial shows copper reduces contamination

While it was not clear how the copper kills micro-organisms, Professor Peter Lambert - one of the lead scientists in the study - suggested it may be through the activity of ions released by the metal.

He also suggested the copper may be attacking membranes in the cell walls of the organisms, preventing them from feeding.

The study found that, when tested, items made from copper had up to 95% fewer micro-organisms on them, compared with the same items made out of standard materials, such as stainless steel.

‘The findings of a 90 – 95% killing of those organisms, even after a busy day on a medical ward with items being touched by numerous people, is remarkable,’ said lead researcher Professor Tom Elliott, a consultant microbiologist and deputy medical director at University Hospitals Birmingham NHS Foundation Trust, which runs Selly Oak Hospital.

‘So it may well offer us another mechanism for trying to defeat the spread of infection.’

The study was a collaboration between Elliott and microbiologists, Lambert at Aston University, Birmingham, and Professor Bill Keevil, of the University of Southampton. It was funded by an education grant provided by the Copper Development Association in the UK.

Laboratory testing conducted at Aston University in Birmingham had demonstrated that the number of common hospital pathogens were significantly reduced when in contact with a copper-containing surface as compared to stainless steel. MRSA , for example, was killed within one hour of contact with the surfaces.

To follow up these findings, in the first clinical study of its kind, items that contained copper, including taps, door push-plates, grab-handles, a toilet seat and a bedside trolley were specially made by local manufacturers and placed in a ward at Selly Oak Hospital.

In the main element of the study, the items were swabbed twice a day, along with similar items made with conventional materials. The samples were taken to Aston University where they were examined to see how many micro-organisms were present.

After the five weeks, the items were swapped over and tested for another five weeks. This unique ‘crossover’ technique was designed to potential bias caused by the items being used in different locations and so in different ways.

Speaking about the use of copper, Lambert said: ‘It’s what I would call an intelligent metal. The copper is quietly working away in the background, killing organisms all the time. It needs to be part of what we call a bundle of care in terms of an approach to preventing infection. This gives us another arm, another weapon to fight infection, which is around us and challenging us all the time. So I would see this in addition to the measures we are taking at the moment.’

Elliott will now lead a larger study, starting next year, to establish how the potential benefits of using copper might best be realised.