Every year, an estimated 450 million people become infected with the virus that causes pneumonia. Four million of them die. Viruses that cause other lung ailments, including MERS and SARS, also concern doctors because of their high mortality rate.
One of the major ways diseases like these are transmitted – even more so than by sneezing – is through contaminated metal and plastic surfaces. People grab onto doorknobs, doorplates, and handles or poles on trains and buses – and then touch their faces.
But studies have shown that surfaces made of copper or a copper alloy destroys those microbes on contact.
Bill Keevil, a microbiologist at Southampton University in England, is investigating the pathogen-destroying properties of copper metal. He points to studies comparing the effectiveness of copper surfaces in U.S. hospitals to the use of traditional hospital door handles and surfaces.
“They found that copper alloys gave a 58 percent reduction in infection rate,” he said. “So that showed, that in the real world of a hospital environment, copper alloys do a great job [in preventing infection].”
In a study published in the journal mBio, Keevil and colleagues report that copper surfaces can rapidly destroy coronavirus 229E, a pathogen which is responsible for the common cold and pneumonia, and is closely related to the one that causes SARS and MERS.
Keevil says copper ions, or electrically charged molecules, kill dangerous viruses by destroying their genetic material, both DNA and RNA.
“Now these ions are able to punch holes in the cell’s membrane, enter the cell and destroy their nucleic acid,” he said. “So, they are completely killed. There’s no chance of mutation leading to resistance and there’s no coming back. So, the chemistry is fantastic.”
Keevil notes ancient civilizations knew about the anti-microbial properties of copper, even if they didn’t understand the biology, as did people of earlier generations.
“It’s ironic in a way, because if you think back to the age of your grandparents and before, copper alloys such as brass were in everyday use in society. And then we developed stainless steel, chrome, plastics and what have you,” he said. “We thought – ‘Hey, these are great modern materials.’ We ripped out the brass-work. Maybe we were a little too clever.”
Copper and copper alloys are a little more expensive than other materials, but Keevil says copper fixtures ultimately end up saving money because hospitals won’t be paying as much to fight infections and for the drugs to treat them.