Clinical trial shows copper continuously reduces bacterial burden by 83% and reduces the risk of infection by 58%.
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 have taken/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
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 published
findings demonstrate that the use of antimicrobial
copper surfaces in intensive care units (ICUs) can reduce the
number of healthcare-associated infections (HCAIs) by 58% as
compared to patients treated in ICUs with non-copper touch
This is the first time an intervention designed to reduce
microbial burden has had a clinical impact on ICU patients.
An overview of the different clinical trials is presented
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 closest proximity to patients and visitors, were
replaced with copper components. No changes were made to clinical
practices or cleaning regimes in the study rooms.
The trial was conducted by infectious disease clinicians and led
by Dr Michael Schmidt, Professor and Vice Chair of the Microbiology
and Immunology Department at MUSC.
The microbial burden (MB) associated with commonly touched
surfaces in ICUs was determined by sampling six objects in 16 rooms
in ICUs in three hospitals over 43 months .
At month 23, copper-alloy surfaces, with inherent antimicrobial
properties, were installed onto six monitored objects in 8 of 16
rooms, and the effect that this application had on the intrinsic MB
present on the six objects was assessed. Census continued in rooms
with and without copper for an additional 21 months.
In concert with routine infection control practices, the average
MB found for the six objects assessed in the clinical environment
during the preintervention phase was 28 times higher (6,985 CFU/100
cm2; n = 3,977 objects sampled) than levels
proposed as benign immediately after terminal cleaning (<250
During the intervention phase, the MB was found to be
significantly lower for both the control and copper-surfaced
objects. Copper was found to cause a significant (83%) reduction in
the average MB found on the objects (465 CFU/100 cm2;
n = 2714 objects) compared to the controls (2,674 CFU/100
cm2; n = 2,831 objects [P <
The introduction of copper surfaces to objects formerly covered
with plastic, wood, stainless steel, and other materials found in
the patient care environment significantly reduced the overall MB
on a continuous basis, thereby providing a potentially safer
environment for hospital patients, health care workers, and
In the same trial, recontamination of copper and plastic bed
rails was compared. Copper, when used to surface hospital bed
rails, was found to consistently limit surface bioburden before and
after cleaning through its continuous antimicrobial activity
The results suggest that replacement of key frequently-touched
surfaces with copper components reduces microbial burden, which
results in a significant and consistent reduction in infection
- Copper reduces the average number of microbes by 83%.
- Based on the total number of microbes measured for each of the
surfaces sampled, the combined MRSA and VRE burdens were 96.8%
lower on copper surfaces than on comparable plastic, wood, metal,
and painted surfaces and were 98.8% lower on the bed rails, the
most heavily burdened object.
- Copper surfaces have been found to substantially diminish the
density of bacteria to levels below those considered a risk to
patients for the acquisition of an infection.
- Microbial burden reduction on copper surfaces continuously
achieves the same levels as terminal cleaning.
- The deployment of copper surfaces in ICUs led to a 58%
reduction in infection rates.
- Copper's antimicrobial activity is continuous - it works
non-stop and around the clock.
In a separate US 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%.
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
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).
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
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
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). 990 copper surfaces
from 90 rooms containing 6 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. Bed rails 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.
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
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.
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 .
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
Further trials are also under way in France, Spain, South
Africa, Greece and Japan.
Copper Surfaces Reduce the Rate of Healthcare-Acquired Infections
in the Intensive Care Unit
Cassandra D Salgado, MD; Kent A Sepkowitz, MD; Joseph F John,
MD; J Robert Cantey, MD; Hubert H Attaway, MS; Katherine D Freeman,
DrPH; Peter A Sharpe, MBA; Harold T Michels, PhD; Michael G
Schmidt, PhD. Infection Control and Hospital Epidemiology , Vol.
34, No. 5, Special Topic Issue: The Role of the Environment in
Infection Prevention (May 2013), pp. 479-486
Sustained Reduction of Microbial Burden on Common Hospital Surfaces
through Introduction of Copper
Michael G Schmidt, Hubert H Attaway, Peter A Sharpe,
Joseph John Jr, Kent A Sepkowitz, Andrew Morgan, Sarah E Fairey,
Susan Singh, Lisa L Steed, J Robert Cantey, Katherine D Freeman,
Harold T Michels and Cassandra D Salgado. J Clin Microbiol July
2012 vol. 50 no. 7 2217-2223. Published ahead of print 2 May 2012,
Copper Continuously Limits the Concentration of Bacteria Resident
on Bed Rails within the Intensive Care Unit
Michael G Schmidt, PhD; Hubert H Attaway III, MS;
Sarah E Fairey, BS; Lisa L Steed, PhD; Harold T Michels, PhD;
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Environment in Infection Prevention (May 2013), pp. 530-533.
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in an Outpatient Infectious Disease Practice
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Fairey, J Hardy, G Miller, Donna Armellino, Wilton R Moran, Peter
Sharpe, Adam Estelle, J H Michel, Harold T Michels and Michael G
Role of Copper in Reducing Hospital Environment Contamination
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Cookson, P Nightingale, L Miruszenko, R Shillam, P Christian and T
S J Elliott, J Hosp Infect (2009),
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Clinical Environment; a Cross-over Study
T J Karpanen, A L Casey, P A Lambert, B D Cookson, P
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and Hospital Epidemiology ( in press).
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Burden (MB) in the Intensive Care Unit (ICU) of Hospital del Cobre,
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G Flores, H Fabres, C Tardito, M Schmidt. Poster 56.044, presented
at the 14th International Conference on Infectious Diseases, Miami,
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Survival of Bacteria on Metallic Copper Surfaces in a
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