Copper has been used since the time of the ancient Egyptians to sterilize water and wounds. Ancient Greeks and Romans used it to treat open sores. Ancient Indians and Persians also recognized its cleansing properties.
They were on to something.
Using two hospitals in Charleston and one in New York, researchers now have data to prove the metal cuts down harmful bacteria in patient rooms.
The Ralph H. Johnson VA Medical Center and the Medical University of South Carolina joined Memorial Sloan-Kettering Cancer Center in a $5 million study funded by the Department of Defense that showed copper hospital bed rails, IV poles and tray tables harbored significantly fewer harmful bacteria than standard ones.
Their next step is to determine whether patients who stayed in rooms with copper equipment suffered fewer costly, and sometimes deadly, hospital-acquired infections.
Michael Schmidt, a microbiology professor at MUSC who is leading the study, said researchers don't know why copper kills bacteria. But even in bacteria-laden hospital rooms, the metal is "continuously acting," he said.
"Surfaces are only cleaned once a day," Schmidt said. "Clorox only works until someone else touches it."
For nearly three years, researchers have collected weekly samples from six intensive-care unit rooms at MUSC, six at Sloan-Kettering and four at the VA.
Half the rooms in each of those hospitals were outfitted with copper bed rails, IV poles, tray tables, call buttons, visitor chair arm rests and electronics used by staff, Schmidt said. The other half had standard equipment.
They studied six types of harmful bacteria. The data showed that copper reduced the presence of harmful bacteria by 97 percent, Schmidt said. One particularly dangerous bacteria, MRSA, known as a "super bug," was not found at all on the copper surfaces, even though "we found it all over the non-copper ones," he said.
Since July, in addition to collecting samples, researchers have reviewed patients' records to determine whether those who stayed in copper-outfitted rooms contracted fewer hospital-acquired infections than the control group. Those results are expected by the end of the year, he said.
About one in 20 patients admitted to the hospital contract such infections in the U.S., according to statistics from the Centers for Disease Control and Prevention. Those infections, which include urinary tract infections to life-threatening staph infections, boost patients' medical bills by an average of more than 200 percent, Schmidt said.
Chuck Stark, who also is involved in the research, said alternative ways of reducing infections are becoming more important as resistance builds up to existing treatments. "It's a solution that does not rely on antibiotics or developing a new drug," he said.
Copper is more expensive than standard equipment, but is less costly than other metals known to be antimicrobial, such as silver. Copper rails would add about $100 to the cost of a standard $30,000 hospital bed, Schmidt said.
By targeting commonly touched equipment, copper could be a large-scale practical answer, Stark said. "It could be useful not just in hospitals, but in nursing homes, schools and public transit," he said.