Copper fittings beat bacteria
Following an international field trial of "Antimicrobial copper surfaces", Asklepios Clinic, in Hamburg, Germany, has fitted door handles and light switches made of special copper alloys combat the spread of antibiotic-resistant bacteria.
During the trial, two hospital wards were equipped with the door handles, door plates and light switches and checked over a period of several months in the summer of 2008 and winter 2008/2009. The adjacent areas kept their usual aluminium, stainless steel or plastic handles and switches.
Independent scientists of the University of Halle-Wittenberg, regularly collected samples and compared the number of bacterium on the different contact surfaces. The desired effect was observed above all on door handles: under normal daily conditions the level of multi-resistant Staphylococci Aureus (MRSA) bacteria decreased by a third, and their resettlement on copper door handles and switches decreased considerably. On wards equipped with copper handles a lowered infection rate in patients was also observed. However, Asklepios points out that this should be examined more thoroughly in larger studies.
‘This clinical effect has surpassed my expectations,’ said Professor Jörg Braun MD, Chief Physician of the I. Medical Department at Asklepios Clinic Wandsbek. The reduction raises hopes that copper based fittings may be a reasonable supplement to existing hygiene measures.
Professor Dietrich H Nies, Director of the Institute for Biology at the Martin-Luther University of Halle-Wittenberg, Germany, and specialist for biometal metabolism, added his positive assessment: ‘Only 63% of the germs were found on the copper surfaces compared with the control surfaces, i.e. common door handles, door plates and light switches. Moreover, it has been shown in practice that copper considerably reduces the resettlement of surfaces with germs.’
The field trial, which took place over 16 weeks in summer and winter, was supported by the German Copper Institute (DKI), after promising laboratory tests had been performed that brought expectations of a significant efficacy of special copper alloys against pathogens in clinical areas. Current research is closing a scientific gap which has existed for a very long time, Asklepios points out. In Ancient Greece, for example, copper was considered to be valuable to ensure good health. ‘Humanity has had positive experience with the hygienic effect of copper for thousands of years,’ added Anton Klassert, DE, Business Manager of the German Copper Institute (DKI) and Head of the European Copper Competence Centre ‘Antimicrobial Properties’ division. ‘It’s fascinating for me to see how the Hamburg research has developed after the preliminary trials since 2008 in Japan and England,’ he said. ‘At the moment, the US Department of Defense is starting a large-scale research project in intensive care units at three clinics in New York City and Charleston, South Carolina.’
Scientists in England, Japan, South Africa, Chile and the US are currently testing various copper alloys to ascertain the most suitable alloy and fields of application. Under laboratory conditions, copper surfaces have been shown to eliminate up to 99% of germs in the shortest period of time. Although frequent hand disinfection is routine for physicians and nurses, along with other hygiene measures, it is not always adequate. ‘We must break new ground to reduce the potential danger for our patients,’ said Professor Braun. Copper alloy surfaces may present an essential contribution to hospital hygiene.