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Copper and copper alloys
dramatically reduce the
presence of MRSA compared
with stainless steel
Like many other hospitals across Europe, Selly Oak Hospital, part of the University Hospital Birmingham NHS Trust, has been fighting superbugs such as MRSA. Laboratory tests at Southampton University have established that the natural antimicrobial properties of copper and copper alloys dramatically reduce the presence of MRSA compared with stainless steel, the most commonly used surface-metal in health institutions. Now the findings will be put to the test in a real hospital environment. If the trial is successful, copper could be installed widely to cut the death-rate from hospital-acquired infections. According to the National Audit Office, 300,000 patients pick up infections in hospital each year in the UK. At least 5,000 are likely to die as a result and the cost to the NHS is estimated at £1bn per year.
Selly Oak was chosen for the Copper Clinical Trial as it is a multi-specialist centre with an advanced microbiology centre. One general medical ward is already having copper installed in preparation for the trial. Because 80% of MRSA transmission is through surface contacts, stainless steel door handles and push-plates are being replaced by copper, along with bathroom taps, toilet flushhandles and grab rails. Even the pens used by the staff will be a high-copper brass. A similar ward next door will retain its traditional metal fittings and will act as a control in the experiment. If the laboratory results are successfully replicated, it is likely that thousands of hospitals across Europe will introduce copper alloy fittings.
The hospital Trust’s deputy medical director, Professor Tom Elliott, says, “Potentially it is very, very exciting if we find that copper actually works in a clinical environment, following the laboratory tests in Southampton and here in Birmingham”. The tests have already been showing striking results. The MRSA bacteria (staphylococci) on stainless steel remained fully active for days. On brass (an alloy of copper and zinc) they died in less than 5 hours and on pure copper the superbugs were eliminated in 30 minutes.
The director of the Environmental Healthcare Unit at Southampton University, Professor Bill Keevil, says that copper suffocates the germs. “The metal reacts with the bacteria and inhibits their respiration – in effect it stops them breathing. In fact if you look back in the literature the Egyptians were using copper thousands of years ago to treat infections!” The tests show that it is not just MRSA that can be killed by copper. The newest threat, the extremely resistant Clostridium difficile can also be killed, as demonstrated by preliminary tests. Scientists are already considering wider medical applications for copper, including a possible defence against bird flu. Experiments by the Southampton team have shown that the metal can kill the human flu virus. Professor Keevil says, “Avian flu is almost identical to normal human flu so, although we haven’t done the work yet, we would predict the same results.”
Copper alloys are available with a range of different physical properties to suit manufacturing processes and end uses, and are available in a range of colours from the flaming red of pure copper to the yellow gold of brass and the silver-grey of bronzes.
When addressing a ‘Designing Against Cross Infection’ at a Building Centre seminar, Angela Vessey commented, “Research on antimicrobial copper and its alloys are compelling. 80% of infectious diseases are transmitted by touch. To the naked eye, stainless steel and aluminium doorknobs and push plates, commonly used in hospitals today, appear to be clean yet can still harbour deadly microbes.”
Angela continued, “Unlike antimicrobial coatings, copper alloys are homogeneous and solid, so the antimicrobial properties last the life of the product and will not suffer deterioration when scratched by jewellery or damaged by sharp implements.
“The antimicrobial effect is seen at copper contents of between 63-99.9%, generally increasing with higher copper content. On a brass surface (80% copper, 20% zinc) there was a significant reduction in live bacteria after 3 hours, with complete inviability after 4.5 hours. The copper-nickel-zinc (55% copper) showed significant and continuing reduction in live bacteria after 4.5 hours. Survival time on stainless steel continued beyond 72 hours.”
For more information about the Copper Development Association go to www.cda.org.uk
