By Harold Michels, PhD
Modern medicine has advanced to the point that it seems almost unconscionable that certain preventable or treatable causes of illness and death still pose an enormous threat. Thomas Frieden, MD, director of the Centers of Disease Control and Prevention (CDC), has named six public health problems that he feels can be reduced. Healthcare-acquired infection (HAI) is one of the priorities identified by the CDC, along with smoking, AIDS, obesity/nutrition, teen pregnancy and auto injuries. There is no magic bullet that will stop hospital infections dead in their tracks, but it is a "winnable battle" as Frieden put it.
Handwashing is universally recognized as the best method for preventing HAI. Both money and lives would be saved if health professionals were to routinely wash their hands according to CDC guidelines before and after coming into contact with patients and medical equipment. Because hand sanitation compliance is not what it should be, the onus is on the healthcare field to find ways to supplement handwashing with other prevention techniques. The World Health Organization recommends – in addition to handwashing – glove use, the identification and isolation of patients at high risk for both contracting and spreading infection, sterilization and disinfection of medical equipment and furniture, and the use of proper laundry protocols. Active surveillance culturing, essentially screening patients for the presence of infectious bacteria and isolating those who test positive, is a relatively new strategy that is becoming more common. A number of states already require pre-admittance surveillance, but this is an ongoing cost borne by hospitals.
What all of these prevention methods have in common is the requirement that healthcare workers take some sort of action: they need to remember to wash their hands before and after patient contact, conscientiously dispose of soiled gowns after use or be vigilant about glove hygiene. What is needed is a passive, continuous solution to infection that will augment current CDC infection prevention guidelines. One place to look for such a solution is the hospital environment.
It is well known that bacteria can survive for extended periods of time on common healthcare touch surfaces in the patient environment. How much and what kind of bacteria was quantified in the first phase of a three-phase clinical trial exploring the role of hospital touch surfaces in the transmission of infectious pathogens. The trial is funded by the U.S. Department of Defense, under the aegis of the Telemedicine and Advanced Technologies Research Center (TATRC), a section of the Army Medical Research and Materiel Command (USAMRMC), and they are being conducted in intensive care unit rooms at three hospitals, Memorial Sloan-Kettering Cancer Center in New York City, the Medical University of South Carolina and the Ralph H. Johnson VA Medial Center, both in Charleston, S.C.
In the first phase of the study, stainless steel, plastic and aluminum objects in intensive care unit rooms were assessed for the concentration of bacteria that was resident on the surface. It was observed that the active clinical environments carried an average microbial burden 35 times higher than the levels commonly accepted as benign (under 500 cfu/100cm2) or total bacteria in spite of strict adherence to CDC recommended infection control program practices. Further, the results showed that the most heavily contaminated objects were those in closest proximity to the patient: bed rails, call buttons and chairs were found to have the highest levels of staphylococcus, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE). These pathogens can survive for extended periods of time on such objects, which act as reservoirs for the bacteria.
In the second phase of the trial, copper bed rails, tray tables, chair arms, call buttons, monitors and IV poles replaced the stainless steel and plastic versions in ICU rooms Copper was effective in reducing the total bacterial load in ICU patient care rooms and on many individual objects within those rooms by approximately 90 percent, when compared to the adjacent rooms where the components were not changed to copper.
The third phase of the study, which is currently underway, is testing whether decreased bioloads on surfaces in patient rooms translates into fewer infections. Further study is needed to assess whether copper touch surfaces can play a role in preventing cross contamination and the transmission of hospital-acquired infections.
The Copper Development Association has funded a complementary study in an infectious disease outpatient clinic at North Shore-Long Island Jewish Health System. The results, which were recently reported in a poster session at the Interscience Conference on Antimicrobial Agents and Chemotherapy, were very similar to the U.S. Army study. It was shown that the microbial burden was decreased on phlebotomy chairs fitted with copper trays and arms. No such reduction was found on standard chairs. What is more, a "halo effect" was evident in the reduction of bacteria on adjacent, non-copper, surfaces of the copperized chairs.
Why copper? Independent laboratory tests prove that copper, brass and bronze kill 99.9 percent of bacteria within two hours. These findings led the Environmental Protection Agency (EPA) to register these materials as public health antimicrobial products that can control VRE, MRSA, Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa and E. coli O157:H7.
Copper surfaces, when cleaned regularly and as a supplement to routine cleaning and disinfection programs, may help reduce the bacterial load on hospital furniture, but copper it is just one potential weapon in the arsenal against HAI. The reality is that it will take innovative scientific research, as well as more of a financial commitment on the part of the healthcare industry and the government, to come to grips with the devastating problem of HAI.
Harold Michels, PhD, is senior vice president of technology and technical services for the Copper Development Association.