A university professor presented research into the mechanism by which copper exerts its antimicrobial effect on antibiotic-resistant organisms last week at the World Health Organization’s first International Conference on Prevention and Infection Control in Switzerland.
Bill Keevil, head of the Microbiology Group and director of the Environmental Healthcare Unit at the University of Southampton in the United Kingdom, noted that the survival of pathogens on conventional hospital touch surfaces contributes to increasing incidence and spread of antibiotic resistance and infections. Keevil proposed antimicrobial copper surfaces as one way to address this problem, since such surfaces achieve a rapid kill of significant bacterial, viral and fungal pathogens.
Keevil reported studies on dry surfaces with a range of pathogens and concluded that: “Copper’s rapid destruction of pathogens could prevent mutational resistance developing and also help reduce the spread of antibiotic resistance genes to receptive and potentially more virulent organisms, as well as genes responsible for virulence.
“Additionally, copper touch surfaces could have a key role in preventing the transmission of healthcare-associated infections. Extensive laboratory tests have demonstrated copper’s antimicrobial efficacy against key organisms responsible for these infections, and clinical trials around the world are now reporting on its efficacy in busy, real-world environments.”
The latest trial — conducted in ICUs at three facilities in the United States — has shown that the use of antimicrobial copper surfaces in ICU rooms resulted in a 40.4% reduction in the risk of acquiring a hospital infection.
The study, funded by the U.S. Department of Defense, was designed to determine the efficacy of antimicrobial copper in reducing the level of pathogens in hospital rooms, and whether such a reduction would translate into a lower rate of infection.
Researchers at the three hospitals involved in the trial — Memorial Sloan Kettering Cancer Center in New York, the Medical University of South Carolina (MUSC) and the Ralph H. Johnson VA Medical Center in Charleston, S.C. — replaced commonly-touched items such as bed rails, overbed tray tables, nurse call buttons and IV poles with antimicrobial copper versions.
Data presented at ICPIC by trial leader Michael Schmidt, PhD, professor and vice chairman of microbiology and immunology at MUSC, demonstrated a 97% reduction in surface pathogens in rooms with copper surfaces. That was the same level achieved by “terminal” cleaning, the regimen conducted after a patient vacates a room.
“Bacteria present on ICU room surfaces are probably responsible for 35% to 80% of patient infections, demonstrating how critical it is to keep hospitals clean,” Schmidt said in a news release. “The copper objects used in the clinical trial supplemented cleaning protocols, lowered microbial levels and resulted in a statistically significant reduction in the number of infections contracted by patients treated in those rooms.”