Antibacterial Copper Fights Hospital Acquired Bacterial Infection

Oct 29, 2011
Tami Port

Native Copper - Jonathan Zander

Heavy metals have long been recognized to have antimicrobial properties. New studies show that copper surfaces can reduce incidence of nosocomial infection.

Although patients seek medical attention to prevent and cure illness, the health care environment is a setting that fosters a dangerous combination both for patients and heath care workers--immune compromised patients mingle with a wide array of dangerous microbes shed by the sick seeking treatment, and spread as healthcare workers move from patient to patient

Threat of Nosocomial Infection

The CDC estimates that 10% of American patients develop nosocomial (hospital-acquired) infections, even though a variety of control measures are used in health care environments to reduce the presence of dangerous microbes, including surface disinfectants, hand washing, and sterile surgery. All of these methods of infectious disease prevention require protocols and active participation by health care staff. Heavy metals, such as copper, can function as a passive antimicrobial on surfaces in the health care environment.

Antimicrobial Copper Reduces Rate of Hospital Acquired Infections

A soon to be published study, funded by the US Department of defense and presented at the annual conference of the Infectious Diseases Society of America in Boston, has again confirmed the usefulness of copper in microbial control. Memorial Sloan Kettering Cancer Center, the Medical University of South Carolina, and the Ralph H. Johnson VA Medical Center participated in this study, in which a variety of frequently touched hospital objects in intensive care units, such as bed rails, tray tables, call buttons and IV poles, were replaced with copper versions. This change resulted in a greater than 95% reduction in bacteria in ICU rooms and 41 percent reduction in the rate of nosocomial infections for ICU patients.

Historic Use of Copper as Antimicrobial

The antimicrobial properties of heavy metals are not actually new news. Water pitchers of brass (an alloy of copper and zinc) have been proven to reduce fecal bacterial counts in water retrieved from rivers when compared to the same water stored in plastic or earthenware vessels, a finding that confirmed the traditional Indian belief that water kept in brass pitchers prevented disease. And silver, another heavy metal, is still used in some surgical dressings and ointments.

Dry Copper Surfaces Effectively Kill Bacteria

And copper ions do not have to be released into water in order to damage bacteria. Bacterial cells have been found to more rapidly take up copper ions from dry surfaces than from moist, resulting in bacterial cell membrane destruction and cell death. Bacteria that can survive on plastic, or stainless steel for days, can be killed within hours of contacting antimicrobial copper.

The Manufacturing Antimicrobial Copper Is Big Business

As a new booming business, many antimicrobial copper manufacturers create products not only for the healthcare environment, but public transit, schools and other public buildings in which this passive bacterial control measure can help prevent the spread of infectious disease.

For more information on microbiology, see the Virtual Microbiology Classroom of the science education website Science Prof Online.

Sources

Bauman, R. (2012) Microbiology with Diseases by Body System. Benjamin Cummings.

Copper Development Association (2011) “ Study Proves New Technology Kills Bacteria That Cause Hospital Infections and Reduces Infection Rates ”, PR Newswire, Sacramento Bee.

Kramer et. al. (2006). "How long do nosocomial pathogens persist on inanimate surfaces? A systematic review", BMC Infectious Diseases 6:130.

Santo, CE, et al (2011) “Bacterial Killing by Dry Metallic Copper Surfaces.” Applied and Environmental Microbiology, p. 794-802, Vol. 77, No. 3