Why Copper Is So Good at Killing Superbugs (And Regular Bacteria, Too)

It's difficult to keep regular hospital beds made of plastic clear of bacteria. (Photo: Monkey Business Images/Shutterstock)

Copper's health benefits have been known for ages — literally.

One of the oldest medical books in the world, the 5,000-year-old Smith Papyrus, details how copper was used in ancient Egypt to sterilize both water and directly treat injuries. Thousands of years later, Hippocrates' texts suggested powdered copper be used to prevent infection of burns and other wounds, and Roman doctors 2,000 years ago used various types of copper treatments for health issues from mouth ulcers to intestinal worms and venereal disease. The Aztecs, Indians and Persians were all known to use copper to treat health concerns, too.

While germ theory wasn't officially recognized by modern medicine until French scientist Louis Pasteur's work in the early 1860s, we now know that copper's effectiveness is tied to its anti-viral and anti-bacterial properties. Obviously, many ancient civilizations had figured this out, even if they didn't understand precisely how copper works.

Which brings us to the present day. While we no longer sprinkle powdered copper oxides on cuts, there are other ways we could use the metal, or its alloys, to keep us healthier — even in the age of the novel coronavirus.

Hospital-acquired infections are the eighth leading cause of death in the United States, killing 100,000 people every year (and getting about 2 million sick). A study published in Applied and Environmental Microbiology showed that copper hospital beds in an Intensive Care Unit had an average of 95 percent fewer bacteria than conventional beds. Most beds are currently made from plastic which is teeming with bacteria. In the study almost 90 percent of samples taken from the plastic rails of hospital beds had unsafe levels of bacteria on them.

"Despite the best efforts by environmental services workers, [hospital beds] are neither cleaned often enough, nor well enough," Michael G. Schmidt, PhD, professor of Microbiology and Immunology, Medical University of South Carolina, Charleston, said in a release from the American Society for Microbiology. Schmidt suggests switching to copper hospital beds as a way to reduce bacteria in hospital settings, and he's been working with a copper bed manufacturer to prove the science behind that suggestion.

More recent research published in the New England Journal of Medicine looked at how long the novel coronavirus, now also known as SARS-CoV-2, lasts on surfaces. On copper no viable SARS-CoV-2 was measured after four hours. For comparison, on stainless steel and plastic, viable virus was detected up to 72 hours after application, though the viral load was lessened.

copper hospital bed
A recent study suggests switching to copper hospital beds is one way to reduce bacteria in hospital settings. (Photo: Bed Techs)

Where copper could be used

Currently, stainless steel or plastics are used for sinks, counters, beds and other surfaces in health care environments, but while stainless steel and plastic are easy to clean (the main reason they're used in such places), it also demonstrably harbors far more bacteria and viruses than a similar copper surface does — and over time, small scratches, dings and holes can hide even more.

It's especially important that the most dangerous superbugs, responsible for the death and illness of already-sick people, are killed by copper. That includes methicillin-resistant staph (MRSA); other staph bacteria; adenoviruses; the flu virus (all types); and even fungus. In a study published in the International Journal of Food Microbiology, 99.9 percent of E.coli bacteria was killed after an hour on a copper table, whereas it survived for weeks on stainless steel.

Considering that last fact, it seems that copper tables and prep areas in restaurants and food-prep areas would be another place copper could make a dent in keeping the nastiest bugs away from vulnerable people.

Copper kills the variety of bacteria and viruses that it does because it works on several levels to disable the organisms, as the video above explains. It binds to proteins that disrupt the basic function of the cell, it breaks down membranes that cause cell drying and then death, and it causes oxidative stress to any cells it comes into contact with, also destroying them.

We're used to seeing copper as a trendy metal in kitchens and bathrooms, or used in pots and pans in kitchens — and using it in these places sure can't hurt. In fact, it would make sense to use copper, especially, in places that see a lot of hands and don't get washed often, like drawer pulls in the kitchen, or bathroom taps.

But the material could be used to save lives in far more fraught and dangerous settings, like hospitals, elder-care facilities, and places where the sickest and most vulnerable of us spend time. That's why there are already several hundred patents for health care surfaces and tools made from copper, though a materials transition will take time, especially where health care budgets are stretched thin or otherwise constrained.