Clinical trials show copper reduces bacterial burden by >97% and the risk of infection by >40%.

Clinical trials investigating Antimicrobial Copper's potential to help fight pathogens that cause healthcare-associated infections are providing proof of efficacy in challenging clinical environments around the world.

Laboratory testing has demonstrated conclusively that Antimicrobial Copper continuously kills bacteria that cause infections and is the most effective touch surface.  Now, clinical trials under way around the world are demonstrating the benefit of Antimicrobial Copper in actual use conditions.  These are taking place in many hospital settings around the world, providing a variety of trial protocols, ward types (geriatric, intensive care and general medical), local clinical strains of organisms and national healthcare environments to put Antimicrobial Copper to the test.

Results show that microbial contamination is significantly and consistently reduced on copper compared to standard surfaces, by greater than 90%.

Results from a US clinical trial, funded by the Department of Defense, take this evidence to a new level by evaluating the connection between contamination on frequently touched surfaces and patient acquisition of infections.  The preliminary findings demonstrate that patients treated in ICU rooms fitted with copper and copper alloy products have a greater than 40% reduction in risk of acquiring an infection.

The preliminary data from this trial was presented at the 1st WHO International Conference on Infection Prevention and Control in July 2011^[1].  This has been supported by a poster at the 19th Annual Health Forum and American Hospital Association Leadership Summit ^[2].

An overview of the different clinical trials is presented below:

US

Three medical centres - The Medical University of South Carolina, Charleston (MUSC), The Ralph H Johnson Veterans Administration Medical Center, Charleston, South Carolina and the Memorial Sloan Kettering Cancer Center in New York City - participated in a clinical trial assessing copper's antimicrobial efficacy in intensive care units (ICUs).  The institutions replaced stainless steel, aluminium and plastic touch surfaces with antimicrobial copper alloys, hereafter referred to as 'copper', on the following frequently-touched objects within selected rooms in each of the ICUs: bed rails, overbed tray tables, chairs, call buttons, data devices and IV poles.

The surfaces shown to be most contaminated and, not surprisingly, in closes proximity to patients and visitors, were replaced with copper components.

During the trial, the level of bacterial contamination on an equivalent number of the selected copper and non-copper surfaces was determined weekly.  No changes were made to clinical practices or cleaning regimes in the study rooms.

The trial, conducted by infectious disease clinicians and led by Dr Michael Schmidt, Professor and Vice Chair of the Microbiology and Immunology Department at MUSC, was executed in three stages:

• The first stage established the baseline microbial burden on the frequently-touched objects in ICU rooms before installation of the copper products. The average microbial burden of the rooms was found to be 16,885 colony forming units (cfu) per 100 cm^{2 [3]}.
• The second stage was the replacement of the most contaminated touch surfaces with copper and subsequent comparison of the microbial burden on these and non-copper equivalent surfaces over a period of 135 weeks. The median bioburden observed on copper surfaces was 97% less than on the control surfaces ^[4].
• The third stage, reported at ICPIC 2011^[1][2], assessed the incidence of healthcare-associated infections in ICU rooms with and without copper products.  Results to date show that there is a significant reduction in the risk of acquiring an infection in rooms where copper products are installed.

The number of copper components in the individual rooms was recorded throughout each patient's stay, e.g. whether or not the patient was in a bed with copper rails (bariatric patients needed special beds which were not available with copper rails).

The preliminary results show that where patients were in a room with 75% of the copper components present (by surface area), they had a 40.4% lower risk of acquiring an infection (N=651, p=0.039). This percentage increased to 61% if the patients were in a 'copper' bed in a copper room (N=541, p=0.006). For patients in a copper room with all copper components present throughout their stay, the risk reduction was 69.1% (N=642, p=0.008).

The results to date suggest that replacement of key frequently-touched surfaces with copper components reduces microbial burden, which results in a significant and consistent reduction in infection rates:

• Copper reduces the median amount of microbes by 97%.
• Virtually no MRSA or VRE were found on the copper surfaces.
• Microbial burden reduction on copper surfaces continuously achieves the same levels as terminal cleaning.
• The deployment of copper surfaces led to a 40 to 70% reduction in infection rates
• Copper's antimicrobial activity is continuous - it works non-stop and around the clock.

In a separate outpatient study, not only was the reduction in microbial bioburden confirmed but a halo effect was observed - reduced contamination in the vicinity of the copper surfaces.  The copper surfaces were shown to reduce the risk of exposure to environmental microbes by 17%^[5].

UK

In the UK, Professor Tom Elliott, Consultant Microbiologist and Deputy Medical Director at University Hospitals Birmingham NHS Foundation Trust, led a trial at Selly Oak Hospital, Birmingham. The trial took place on a general medical ward fitted with both copper and standard components. It aimed to demonstrate copper's ability to reduce environmental contamination and improve patient outcomes as part of a 'care bundle' - a package of measures to fight infection.

The first results from the trial, following sampling of three products - taps, push plates and toilet seats - were presented at the Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) in Washington DC, USA, in October 2008. These results show that surfaces made from materials that contain copper kill a wide range of potentially harmful micro-organisms, significantly reducing the number of these organisms that can come into contact with patients, visitors and staff. Data from the three products sampled over a ten-week period showed that items made from copper had 90 - 100% fewer micro-organisms on them, compared with the same items made from standard materials (chrome-plated brass, aluminium and plastic)^[6].

Professor Elliott explains: "What this must mean is that the risk of picking up an infection is reduced, because we know that one of the vehicles where organisms can spread from one surface to another is by touching them. So the results are very exciting.

"The findings of a 90 to 100% killing of those organisms, even after a busy day on a medical ward with items being touched by numerous people, is remarkable. So it may well offer us another mechanism for trying to defeat the spread of infection."

The copper products installed for the clinical trial - door furniture, bathroom fittings, trolleys and overbed tables, have all been subject to the standard NHS cleaning protocols and formulations, including toilet and spillage cleaning. During the 24-36 months after installation, only some mild surface oxidation has taken place. With their copper, gold and bronze colours, the copper components appear markedly different to the standard components but were widely accepted by staff, patients and visitors.

The second phase of the trial involved sampling of the full range of copper and control surfaces over a period of 6 months to gather more data.  Results reinforce the earlier findings, showing significantly lower levels of contamination on the copper surfaces compared to controls.  The paper reporting on the second phase of the UHB Selly Oak clinical trial is now in press ^[7].

Chile

In Chile, 70,000 nosocomial infections are reported each year, most commonly from common hospital-borne pathogens such as S. aureus, P aeruginosa and A. baumanii.

In a 30-week clinical trial at the Hospital del Cobre, in Calama, extensive microbial analyses were implemented at the facility's intensive care unit (ICU).  Nine hundred and ninety copper surfaces from 90 rooms containing six different copper objects were studied against an equivalent number of rooms and surfaces containing non-copper objects.  Over-bed tables were made from copper alloy C70600.  Bedrails were clad with copper alloy C11000 foils.  Visitor chairs were fitted with copper alloy C70600 armrests.  Copper alloy C71000 intravenous poles were provided.  Writing pens used to input data on a touch screen were made from brass (70% Cu, 30% Zn).

Results of this clinical trial demonstrated an approximately 90% reduction of microorganisms on the copper items compared to the controls after ten weeks.  A reduction in the total microbial burden was seen for each class of microbe evaluated.   Furthermore, continuous antimicrobial activity of copper persisted throughout the study^[8].

Copper was effective in reducing microbial loads on all 6 surfaces tested (ie bed rails by 91%, bed levers by 82%, tray tables by 83%, chair arms by 92%, monitor pens by 49% and IV poles by 88%).

Average microbial burden counts in rooms with copper touch surfaces were significantly lower than rooms without copper surfaces.  Staphylococci were the most predominant microorganism isolated and copper was effective in reducing the Staphylococci microbial burden.

Germany

In the Asklepios Clinic, Wandsbek, in Hamburg, Germany, aluminium door handles and plastic light switches in a geriatric ward and its adjacent bathrooms have been replaced by copper alloy equivalents. The patients in the control and trial wards have similar profiles. The results to date show a significant reduction in contamination on the copper components ^[9].

Finland

A trial conducted at a nursing home, in conjunction with the Helsinki University Department of Public Health, compared contamination on copper vs standard items in patient rooms, bathrooms and communal areas. Copper components included dressing trolleys, door handles, grab rails, handrails, shower drains and push buttons. The first results show higher levels of contamination on the non-copper items and presence of faecal and urinary bacteria, (Staphylococcus aureus, E. coli and Candida albicans) only on stainless steel, plastic and chromium components. On copper and copper alloy surfaces, only Gram-positive bacilli and cocci and normal environmental and skin flora were found.

Other

Further trials are also under way in France, Spain, South Africa^[10], Greece and Japan.

[1] M G Schmidt, BMC Proceedings 2011, 5(Suppl 6):053 (Oral presentation delivered at 1st International Conference on Prevention and Infection Control, June 29-July 2 2011, Geneva, Switzerland.  Further information.

[2] Risk Mitigation of Hospital Acquired Infections Through the Use of Antimicrobial Copper Surfaces
W R Moran, H H Attaway, M G Schmidt, J F John, C D Salgado, K A Sepkowitz, R J Cantey, L L Steed, H T Michels. Poster presented at the American Hospital Association and Health Forum Leadership Summit 2011, July 17-19, 2011, San Diego, CA.

[3] Microbial Burden of Objects in ICU Rooms
C D Salgado, K A Sepkowitz, T Plaskett, J F John, J R Cantey, H H Attaway, L L Steed, H T Michels, M G Schmidt. October 2008.

[4] A Pilot Study to Determine the Effectiveness of Copper in Reducing the Microbial Burden (MB) of Objects in Rooms of Intensive Care Unit (ICU) Patients
C D Salgado, A Morgan, K A Sepkowitz, J F John, J R Cantey, H H Attaway, T Plaskett, L L Steed, H T Michels, M G Schmidt.  Poster 183, 5th Decennial International Conference on Healthcare-Associated Infections, Atlanta, March 29, 2010

[5] Copper Surfaces Reduce Microbial Burden in Out-Patient Infectious Disease Practice
B E Hirsch, H Attaway, R Nadan, S Fairey, J Hardy, G Miller, S Rai, D Armellino, M Schilling, W Moran, P Sharpe, A Estelle, J H Michel, H T Michels, M G Schmidt -  presented in a poster session at the Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) in Boston, MA, September 13, 2010.

[6] Role of Copper in Reducing Hospital Environment Contamination
A L Casey, D Adams, T J Karpanen, P A Lambert, B D Cookson, P Nightingale, L Miruszenko, R Shillam, P Christian and T S J Elliott, J Hosp Infect (2009), doi:10.1016/j.jhin.2009.08.018.

[7] The Antimicrobial Efficacy of Copper Alloy Furnishing in the Clinical Environment; a Cross-over Study
T J Karpanen, A L Casey, P A Lambert, B D Cookson, P Nightingale, L Miruszenko L and T S J Elliott. Infection Control and Hospital Epidemiology ( in press).

[8] Effectiveness of Copper Contact Surfaces in Reducing the Microbial Burden (MB) in the Intensive Care Unit (ICU) of Hospital del Cobre, Calama, Chile
V Prado, C Durán, M Crestto, A Gutierrez, P Sapiain, G Flores, H Fabres, C Tardito, M Schmidt. Poster 56.044, presented at the 14th International Conference on Infectious Diseases, Miami, March 11, 2010.

[9] Survival of Bacteria on Metallic Copper Surfaces in a Hospital Trial
André Mikolay, Susanne Huggett, Ladji Tikana, Gregor Grass, Jörg Braun and Dietrich H Nies. Applied Microbial and Cell Physiology, DOI 10.1007/s00253-010-2640-1. May 2010

[10] Antimicrobial Efficacy of Copper Touch Surfaces in Reducing Environmental bioburden in a South African Community Healthcare Facility
F Marais, S Mehtar and L Chalkley, J Hosp Infect (2009), doi:10.1016/j.jhin.2009.07.010.