Tuesday 4 December 2012

Copper 'restricts the global spread of antibiotic-resistant infections'

New research from the University of Southampton in the UK has shown that copper can prevent horizontal transmission of genes, which has contributed to the increasing number of antibiotic-resistant infections worldwide.

Horizontal gene transfer (HGT) in bacteria is largely responsible for the development of antibiotic-resistance, which has led to an increasing number of difficult-to-treat healthcare-associated infections (HCAIs). 

The newly-published paper, which appears in the journal mBio, shows that while HGT can take place in the environment, on frequently-touched surfaces – such as door handles, trolleys and tables – made from stainless steel, copper prevents this process from occurring and rapidly kills bacteria on contact.

Lead author Professor Bill Keevil, Chair in Environmental Healthcare at the University of Southampton, summarises: "We know many human pathogens survive for long periods in the hospital environment and can lead to infection, expensive treatment, blocked beds and death. What we have shown in this work is the potential for strategically-placed antimicrobial copper touch surfaces to not only break the chain of contamination, but also actively reduce the risk of antibiotic resistance developing at the same time. Provided adequate cleaning continues in critical environments, copper can be employed as an important additional tool in the fight against pathogens." 

Beyond the healthcare environment, copper also has a wider role to play in infection control. Professor Keevil explains: "Copper touch surfaces have promise for preventing antibiotic resistance transfer in public buildings and mass transportation systems, which lead to local and – in the case of jet travel – rapid worldwide dissemination of multidrug-resistant superbugs as soon as they appear. 

"People with inadequate hand hygiene from different countries could exchange their bugs and different antibiotic resistance genes just by touching a stair rail or door handle, ready to be picked up by someone else and passed on. Copper substantially reduces and restricts the spread of these infections, making an important contribution to improved hygiene and, consequently, health." 

Installations of copper touch surfaces have already taken place across the UK and around the world, harnessing copper's ability to continuously reduce bioburden and consequently the risk of HCAI transmission. This research highlights an additional benefit, adding to the compelling body of evidence that copper offers an important adjunct to existing infection control practices.