Antimicrobial copper alloy touch surfaces
Encyclopedia
Antimicrobial copper alloy touch surfaces are surfaces that are made from alloy
s of the metal copper
, such as brass
and bronze
. The phrase "touch surfaces" means all the various kinds of surfaces (such as door knobs, railings
, tray tables, etc.) that are often touched by people at work or in everyday life, especially (for example) in hospital
s and clinic
s.
Touch surfaces that are in frequent use and that are not made with copper alloys can easily accumulate a variety of harmful microbes (virus
es, bacteria
, etc.). These microbes can often survive on touch surfaces for surprisingly long periods of time (e.g., for more than 30 days on some popular materials). However, copper and copper alloys have a natural ability to kill harmful microbes relatively rapidly - often within two hours or less (i.e. copper alloy surfaces are antimicrobial
).
This natural ability of copper alloys to kill a wide range of microbes deposited on the alloys’ surfaces has been proven by an extensive body of research. The research also suggests that if touch surfaces are made with copper
alloys, the reduced or totally destroyed microbial populations on the antimicrobial alloys may ultimately reduce the incidence of transmission of disease-causing organisms.
Current knowledge regarding the antimicrobial properties of copper alloy touch surfaces, results of clinical trials conducted at hospitals around the world, and USEPA's registrations of 355 different copper alloys as "antimicrobial materials" with public health benefits are discussed in this article.
Copper alloy surfaces have intrinsic properties to destroy a wide range of microorganisms. In the interest of protecting public health, especially in heathcare environments with their susceptible patient populations, an abundance of peer-reviewed antimicrobial efficacy studies have been and continue to be conducted around the world regarding copper’s efficacy to destroy E. coli
O157:H7, methicillin
-resistant Staphylococcus aureus
(MRSA), Staphylococcus
, Clostridium difficile
, influenza A virus, adenovirus
, and fungi
.
Much of this antimicrobial efficacy work has been or is currently being conducted at the University of Southampton
and Northumbria University
(United Kingdom
), University of Stellenbosch (South Africa
), Panjab University (India
), University of Chile (Chile
), Kitasato University
(Japan
), the Instituto do Mar and University of Coimbra (Portugal
), and the University of Nebraska and Arizona State University
(U.S.A.)
Using a three dimensional strategy providing more contact with the bacteria, a patents pending paint offers another alternative. The paint is entitled Bacterm and independently tested to kill the same bacteria in 30 minutes versus two hours. Lab results viewable by logging onto www.bacterm.com
In the USA, in order to qualify copper and its alloys as registered antimicrobial substances under that nation’s federal pesticide regulations, an extensive additional body of efficacy testing under Good Laboratory Practice
guidelines by an EPA-approved laboratory was required by the USEPA. After these tests were concluded in 2008, registrations of 282 different copper alloys were granted.
Touch surfaces commonly found in hospital rooms, such as bed rails, call buttons, touch plates, chairs, door handles, light switches, grab rails, intravenous poles, dispensers (alcohol gel, paper towel, soap), dressing trolleys, and counter and table tops are known to be contaminated with high levels of potentially dangerous bacteria
, including Staphylococcus
, Methicillin-resistant Staphylococcus aureus
(MRSA), one of the most virulent strains of antibiotic-resistant bacteria and Vancomycin-resistant Enterococcus
(VRE). Objects in closest proximity to patients have the highest levels of staphylococcus, MRSA, and VRE. This is why touch surfaces in hospital rooms can serve as abundant sources, or reservoirs, for the spread of bacteria from the hands of healthcare workers and visitors to patients.
Hand and surface disinfection
practices are the first line of defense against infection. However, these have fallen short of expectations as opportunistic organisms put patients and healthcare workers at risk. Since approximately 80% of infectious diseases are known to be transmitted by touch, and pathogens found in healthcare facilities can survive on inanimate surfaces for days and even months, the microbial burden of frequently touched surfaces is believed to play a significant role in infection causality. Surfaces in hospitals and healthcare facilities are frequently touched and therefore could become reservoirs of infection.
Recently, to evaluate their effectiveness as secondary infection control measures, these products have been made from copper and its alloys and deployed in hospital geriatric wards, intensive care unit
s, and general medical wards around the world.
Clinical trial
s are being conducted on microbial strains unique to individual healthcare facilities around the world to evaluate to what extent copper alloys can reduce the incidence of infection in hospital environments.
The success of these clinical trials to date, which are summarized here, are prompting hospitals around the world to specify antimicrobial copper touch surfaces as an additional weapon in the fight against infection.
, around 300,000 patients contract nosocomial infection
s each year and at least 5,000 patients die of complications from infections contracted in hospitals.
For these reasons, a cross-over clinical trial (a test method designed to eliminate variability bias from patients, staff, cleaning efficacy, outbreaks, etc.) evaluating antimicrobial copper alloys was carried out at Selly Oak Hospital over an 18-month period in 2007-2008 by the University Hospital Birmingham NHS Trust
and Aston University
.
Frequently touched surfaces typically manufactured with standard materials (i.e., plastic, chrome, aluminum) were replaced with copper alloys. These included a copper alloy set of sink tap handles (60% Cu, 40% Zn) and a ward entrance door push plate (70% Cu, 30% Zn).
Contamination reductions of 90-100% were observed for Staphylococcus aureus
, Escherichia coli
, Klebsiella pneumoniae
, Acinetobacter baumanii, Enterococcus spp., and Candida albicans
on the copper alloy surfaces versus the non-copper standard surfaces. A microorganism reduction of 100% was observed on the hot tap copper alloy handle.
The high degree of clinical performance suggested that copper alloy surfaces may increase the effectiveness of existing infection control practices and may lower the risk of infections acquired in healthcare facilities.
Based on the results of this and other laboratory and clinical studies, St. Francis Private Hospital, a 140-bed facility located in Mullingar, County Westmeath, Ireland
, decided to become the first hospital in the world to fully specify hygienic copper door handles throughout its facility as part of its infection control program. A full upgrade of all door furniture (i.e., 250 doorsets, incorporating handles, push plates and privacy locks) to antimicrobial copper in the hospital and nursing home commenced in January 2010.
Healthcare architects in the United Kingdom are now specifying antimicrobial copper. Refurbishment projects specifying copper products are anticipated across NHS Trust
facilities.
, 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 ninety 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-the-bed tables were made from copper alloy C70600. Bedrails were cladded 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 (i.e., bed rails by 91%, bed levers by 82%, tray tables by 83%, chair arms by 92%, monitor pen by 49%, and IV poles by 88%).
Average microbial burden counts in rooms with copper touch surfaces were significantly lower than in rooms without copper surfaces. Staphylococci were the most predominant microorganism isolated and copper was effective in reducing the Staphylococci microbial burden. Further studies regarding the clinical implications of copper’s intrinsic ability to reduce microbial burdens in hospitals are being planned.
School of Medicine conducted antimicrobial studies of S. aureus
, E. coli, and P. aeruginosa on various Japan
ese copper alloy coins and on copper alloy plates. The microbes were strains from hospital environments. Copper and its nickel-silver, cupronickel
, and brass
alloys were found to kill the bacteria within a short time. In another experiment, bacterial colonies were investigated on ball point pens made with and without copper alloys. Total bacterial colonies on the copper pens were much lower than on the non-copper pens: 2.1 CFU
versus 47.8 CFU. Staphyloccocus counts on copper ball point pens were also much lower: 0.7 CFUs versus 20.8 CFUs on non-copper pens.
Due to the success of these results, a 2-year clinical trial was conducted to monitor contamination levels of nosocomial bacteria in the dermatology
ward and neonatal intensive care unit
(NICU) at Kitasato University
Hospital. The antimicrobial efficacy of copper on floors, sinks, push plates, showerheads and doorknobs was evaluated by comparing bacterial loads on these surfaces and on their non-copper counterparts.
The number of viable Staphylococcus
spp. organisms on surfaces containing copper and its alloy were reduced by half to one-thirtieth of that on control surfaces, depending upon surface humidity and the frequency of contact. Similar definitive findings were also obtained for Pseudomonas aeruginosa
.
Various metals were evaluated for their antimicrobial efficacies, including copper
alloys, zinc
, nickel
, tin
, silver
, and gold
. Antimicrobial efficacies generally followed Lewis acidity values of the various metals. Silver, a prohibitively expensive precious metal
, had the highest bactericidal activity; copper came in second. The study also found that contact dermatitis
allergies rarely occur if copper is used as a hygienic touch material.
The bactericidal activity of copper was also tested against two strains of MRSA and S. aureus
in vitro to determine whether copper alloys are effective in preventing the spread of contamination on the touch surface products used in the hospital ward. MRSA and S. aureus counts fell below detection limits within 180 minutes. The results indicated that copper has a strong bactericidal effect against S. aureus, including MRSA.
When a copper plate was situated on a MRSA-infected floor in the dermatology ward around a bed of a MRSA-infected patient, the bacterial count of S. aureus, including MRSA and the other Staphylococcus
on the floor covered with a copper plate was significantly less than on a floor unprotected by copper alloys. These results suggested that the copper plate helped to prevent the spread of MRSA contamination in the hospital.
(MTB) is responsible for the spread of tuberculosis
in South Africa
n hospitals. Test strains of Candida albicans
, Pseudomonas aeruginosa
, Klebsiella pneumoniae
meticillin-resistant Staphylococcus aureus
(MRSA), and MTB were isolated from South African patients at a hospital’s intensive care unit in order to establish the minimum in-vitro copper concentrations to produce sterilization
against these microbes and yeast
. Acinetobacter baumannii
was isolated from a patient in a burn unit and two clinical strains of MTB were collected and tested.
Copper and its alloys demonstrated antimicrobial activities against multiple-antibiotic-resistant nosocomial bacteria and C. albicans
isolated from the hospital, whereas stainless steel
and PVC
did not. Copper and its alloys showed a marked inhibitory effect (88-98%) on MTB despite the strain’s drug resistance. The researchers concluded that the minimum concentration of copper to be an effective antimicrobial agent is >55% for yeasts and bacteria. Higher concentrations of copper were found to be necessary to inhibit MTB.
(CDC), regarding the effectiveness of copper alloys in reducing microbial loads and cross infection in healthcare environments. For this reason, clinical trials at three major US hospitals are currently examining environmental bacterial loads, infection rates, and impacts on cross-contamination in intensive care unit (ICU) rooms retrofitted with copper touch surfaces versus rooms without copper surfaces.
The trials are funded by the U.S. Department of Defense (DOD) under the Telemedicine and Advanced Technologies Research Center (TATRC), a section of the United States Army Medical Research and Materiel Command
(USAMRMC). DOD has extraordinary interests in the potential for antimicrobial copper surfaces to reduce hospital-acquired infections because it wants to prevent hospital-acquired infections among thousands of its enlisted armed forces servicemen and servicewomen who have been injured in recent conflicts. TATRC, which funds a Military Infectious Disease Program has been granted funds by the United States Congress
to evaluate the antimicrobial effectiveness of copper, brass and bronze alloys. The studies are coordinated through the Advanced Technology Institute in Charleston, South Carolina.
The clinical studies involve intensive care units (ICUs) at Memorial Sloan-Kettering Cancer Center
in New York City, one of the world’s most prestigious cancer facilities, the Medical University of South Carolina
, and the Ralph H. Johnson VA Medical Center in Charleston
, South Carolina
.
An evaluation of the microbial burden of various objects in the ICU rooms has been documented and is available.
Early results disclosed in 2011 indicate that the coppered rooms demonstrated a 97% reduction in surface pathogens versus the non-coppered rooms. This reduction is the same level achieved by “terminal” cleaning regimens conducted after patients vacate their rooms. Furthermore, of critical importance to health care professionals, the preliminary results indicated that patients in the coppered ICU rooms had a 40.4% lower risk of contracting a hospital acquired infection versus patients in non-coppered ICU rooms. The U.S. Department of Defense investigation contract, which is ongoing, will also evaluate the effectiveness of copper alloy touch surfaces to prevent the transfer of microbes to patients and the transfer of microbes from patients to touch surfaces, as well as the potential efficacy of copper-alloy based components to improve indoor air quality
.
The latest results from the studies at the three institutions will be developed into a manuscript for publication.
In a separate initiative not funded by the U.S. Department of Defense, clinical trials at an infectious disease outpatient ward consisting of patients with HIV
and other infectious disease
s are being conducted at North Shore University Hospital
in Manhasset, New York
. An alloy of 90% Cu 10% Ni significantly lowered the microbial burden, primarily Staphylococci, on arm surfaces of phlebotomy
chairs versus wooden arm surfaces. The median reduction for total bacteria on the copper alloy chairs arms was 90%. Use of the chair with copper arm tops resulted in a 17-fold lower risk of exposure to environmental microbes than when patients used the standard chair. The majority of the samples from the chairs with copper components were below the 500 CFU/ cm2 level believed to represent a risk to hospital patients.
The microbiocidal properties of the copper chair arms were able to confer an ‘antimicrobial halo’ within the general vicinity of the arm top. The microbial burden associated with the wooden side arms of the copper covered chair arms was 70%, lower than those on the control chair. This halo effect may help to help reduce the transfer of pathogenc bacteria.
Similarly, patients and healthcare workers who used chairs with copper trays were subjected to a 15-fold lower risk than the patients using chairs with composite trays. The microbial burden on copper trays was reduced by 88% compared to the composite plastic surface.
(EPA) approved the registrations of five different groups of copper
alloys as “antimicrobial
materials” with public health benefits. The EPA registrations now cover 355 different compositions of copper alloys within these groups. All of the alloys have minimum nominal copper concentrations of 60%. The results of the EPA-supervised antimicrobial studies, demonstrating copper's strong antimicrobial efficacies across a wide range of alloys, were recently published.
These copper alloys are the only solid surface materials to be granted “antimicrobial public health claims” status by EPA. Before these registrations were granted, only antimicrobial gases, liquids, sprays, and concentrated powders, including sterilizers, disinfectants and antiseptics, were registered to make antimicrobial public health claims.
destroyed by copper alloys in the EPA-supervised antimicrobial efficacy tests include:
To attain the EPA registrations, the copper alloy groups had to demonstrate strong antimicrobial efficacies according to all of the following rigorous tests:
The EPA registration numbers for the six groups of alloys are as follows:
The registrations state that “antimicrobial copper alloys may be used in hospitals, other healthcare facilities, and various public, commercial and residential buildings.”
of antimicrobial copper alloy products. CDA must ensure that manufacturers promote these products in an appropriate manner. Manufacturers must only promote the proper use and care of these products and must specifically emphasize that the use of these products is a supplement and not a substitute to routine hygienic practices.
EPA mandated that all advertising and marketing materials for antimicrobial copper products contain the following statement:
Antimicrobial copper alloys are intended to provide supplemental antimicrobial action in between routine cleaning of environmental or touch surfaces in healthcare settings, as well as in public buildings and the home. Users must also understand that in order for antimicrobial copper alloys to remain effective, they cannot be coated in any way.
CDA is currently implementing an outreach program through written communications, a product stewardship website, and through a Working Group which meets periodically to expand educational efforts.
More than 100 different potential product applications were cited in the registrations for their potential public health benefits.
Note: With the exception of the product name and the percentage of active ingredient, the EPA-approved Master Labels for the six groups of registered alloys are identical.
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...
s of the metal copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
, such as brass
Brass
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin...
and bronze
Bronze
Bronze is a metal alloy consisting primarily of copper, usually with tin as the main additive. It is hard and brittle, and it was particularly significant in antiquity, so much so that the Bronze Age was named after the metal...
. The phrase "touch surfaces" means all the various kinds of surfaces (such as door knobs, railings
Handrail
A handrail is a rail that is designed to be grasped by the hand so as to provide stability or support. Handrails are commonly used while ascending or descending stairways and escalators in order to prevent injurious falls. Other applications include bathroom handrails—which help to prevent falls on...
, tray tables, etc.) that are often touched by people at work or in everyday life, especially (for example) in hospital
Hospital
A hospital is a health care institution providing patient treatment by specialized staff and equipment. Hospitals often, but not always, provide for inpatient care or longer-term patient stays....
s and clinic
Clinic
A clinic is a health care facility that is primarily devoted to the care of outpatients...
s.
Touch surfaces that are in frequent use and that are not made with copper alloys can easily accumulate a variety of harmful microbes (virus
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...
es, bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
, etc.). These microbes can often survive on touch surfaces for surprisingly long periods of time (e.g., for more than 30 days on some popular materials). However, copper and copper alloys have a natural ability to kill harmful microbes relatively rapidly - often within two hours or less (i.e. copper alloy surfaces are antimicrobial
Antimicrobial
An anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...
).
This natural ability of copper alloys to kill a wide range of microbes deposited on the alloys’ surfaces has been proven by an extensive body of research. The research also suggests that if touch surfaces are made with copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
alloys, the reduced or totally destroyed microbial populations on the antimicrobial alloys may ultimately reduce the incidence of transmission of disease-causing organisms.
Current knowledge regarding the antimicrobial properties of copper alloy touch surfaces, results of clinical trials conducted at hospitals around the world, and USEPA's registrations of 355 different copper alloys as "antimicrobial materials" with public health benefits are discussed in this article.
Antimicrobial properties of copper alloy touch surfaces
For a detailed discussion regarding antimicrobial efficacy experiments on various copper alloy touch surfaces, see: Antimicrobial efficacy of copper alloy touch surfaces.Copper alloy surfaces have intrinsic properties to destroy a wide range of microorganisms. In the interest of protecting public health, especially in heathcare environments with their susceptible patient populations, an abundance of peer-reviewed antimicrobial efficacy studies have been and continue to be conducted around the world regarding copper’s efficacy to destroy E. coli
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
O157:H7, methicillin
Methicillin
Meticillin or methicillin is a narrow-spectrum beta-lactam antibiotic of the penicillin class. It should not be confused with the antibiotic metacycline.-History:Methicillin was developed by Beecham in 1959...
-resistant Staphylococcus aureus
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
(MRSA), Staphylococcus
Staphylococcus
Staphylococcus is a genus of Gram-positive bacteria. Under the microscope they appear round , and form in grape-like clusters....
, Clostridium difficile
Clostridium difficile
Clostridium difficile , also known as "CDF/cdf", or "C...
, influenza A virus, adenovirus
Adenoviridae
Adenoviruses are medium-sized , nonenveloped icosahedral viruses composed of a nucleocapsid and a double-stranded linear DNA genome...
, and fungi
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...
.
Much of this antimicrobial efficacy work has been or is currently being conducted at the University of Southampton
University of Southampton
The University of Southampton is a British public university located in the city of Southampton, England, a member of the Russell Group. The origins of the university can be dated back to the founding of the Hartley Institution in 1862 by Henry Robertson Hartley. In 1902, the Institution developed...
and Northumbria University
Northumbria University
Northumbria University is an academic institution located in Newcastle upon Tyne in the North East of England. It is a member of the University Alliance.- History :...
(United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
), University of Stellenbosch (South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
), Panjab University (India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
), University of Chile (Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
), Kitasato University
Kitasato University
is one of the famous private university in Minato, Tokyo, Japan.The head of the university is located in the Shirokane Campus, neighboring the Kitasato Institute. Its major educational facilities are located in the Sagamihara Campus, located 60 kilometers west of central Tokyo...
(Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
), the Instituto do Mar and University of Coimbra (Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...
), and the University of Nebraska and Arizona State University
Arizona State University
Arizona State University is a public research university located in the Phoenix Metropolitan Area of the State of Arizona...
(U.S.A.)
Using a three dimensional strategy providing more contact with the bacteria, a patents pending paint offers another alternative. The paint is entitled Bacterm and independently tested to kill the same bacteria in 30 minutes versus two hours. Lab results viewable by logging onto www.bacterm.com
In the USA, in order to qualify copper and its alloys as registered antimicrobial substances under that nation’s federal pesticide regulations, an extensive additional body of efficacy testing under Good Laboratory Practice
Good Laboratory Practice
In the experimental research arena, the phrase good laboratory practice or GLP specifically refers to a quality system of management controls for research laboratories and organizations to try to ensure the uniformity, consistency, reliability, reproducibility, quality, and integrity of chemical ...
guidelines by an EPA-approved laboratory was required by the USEPA. After these tests were concluded in 2008, registrations of 282 different copper alloys were granted.
Clinical trials of antimicrobial copper alloy touch surfaces in healthcare facilities
Microorganisms are known to survive on inanimate ‘touch’ surfaces for extended periods of time. This can be especially troublesome in hospital environments where patients with immunodeficiencies are at enhanced risk for contracting nosocomial infections (hospital-borne infections), often with fatal consequences.Touch surfaces commonly found in hospital rooms, such as bed rails, call buttons, touch plates, chairs, door handles, light switches, grab rails, intravenous poles, dispensers (alcohol gel, paper towel, soap), dressing trolleys, and counter and table tops are known to be contaminated with high levels of potentially dangerous bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
, including Staphylococcus
Staphylococcus
Staphylococcus is a genus of Gram-positive bacteria. Under the microscope they appear round , and form in grape-like clusters....
, Methicillin-resistant Staphylococcus aureus
Methicillin-resistant Staphylococcus aureus
Methicillin-resistant Staphylococcus aureus is a bacterium responsible for several difficult-to-treat infections in humans. It is also called multidrug-resistant Staphylococcus aureus and oxacillin-resistant Staphylococcus aureus...
(MRSA), one of the most virulent strains of antibiotic-resistant bacteria and Vancomycin-resistant Enterococcus
Vancomycin-Resistant Enterococcus
Vancomycin-resistant Enterococcus, or vancomycin-resistant enterococci , are bacterial strains of the genus Enterococcus that are resistant to the antibiotic vancomycin. To become VRE, vancomycin-sensitive enterococci typically obtain new DNA in the form of plasmids or transposons which encode...
(VRE). Objects in closest proximity to patients have the highest levels of staphylococcus, MRSA, and VRE. This is why touch surfaces in hospital rooms can serve as abundant sources, or reservoirs, for the spread of bacteria from the hands of healthcare workers and visitors to patients.
Hand and surface disinfection
Disinfection
Disinfectants are substances that are applied to non-living objects to destroy microorganisms that are living on the objects. Disinfection does not necessarily kill all microorganisms, especially nonresistant bacterial spores; it is less effective than sterilisation, which is an extreme physical...
practices are the first line of defense against infection. However, these have fallen short of expectations as opportunistic organisms put patients and healthcare workers at risk. Since approximately 80% of infectious diseases are known to be transmitted by touch, and pathogens found in healthcare facilities can survive on inanimate surfaces for days and even months, the microbial burden of frequently touched surfaces is believed to play a significant role in infection causality. Surfaces in hospitals and healthcare facilities are frequently touched and therefore could become reservoirs of infection.
Recently, to evaluate their effectiveness as secondary infection control measures, these products have been made from copper and its alloys and deployed in hospital geriatric wards, intensive care unit
Intensive Care Unit
thumb|220px|ICU roomAn intensive-care unit , critical-care unit , intensive-therapy unit/intensive-treatment unit is a specialized department in a hospital that provides intensive-care medicine...
s, and general medical wards around the world.
Clinical trial
Clinical trial
Clinical trials are a set of procedures in medical research and drug development that are conducted to allow safety and efficacy data to be collected for health interventions...
s are being conducted on microbial strains unique to individual healthcare facilities around the world to evaluate to what extent copper alloys can reduce the incidence of infection in hospital environments.
The success of these clinical trials to date, which are summarized here, are prompting hospitals around the world to specify antimicrobial copper touch surfaces as an additional weapon in the fight against infection.
Clinical trial in the United Kingdom
In the United KingdomUnited Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, around 300,000 patients contract nosocomial infection
Nosocomial infection
A nosocomial infection , also known as a hospital-acquired infection or HAI, is an infection whose development is favoured by a hospital environment, such as one acquired by a patient during a hospital visit or one developing among hospital staff...
s each year and at least 5,000 patients die of complications from infections contracted in hospitals.
For these reasons, a cross-over clinical trial (a test method designed to eliminate variability bias from patients, staff, cleaning efficacy, outbreaks, etc.) evaluating antimicrobial copper alloys was carried out at Selly Oak Hospital over an 18-month period in 2007-2008 by the University Hospital Birmingham NHS Trust
NHS Trust
A National Health Service trust provides services on behalf of the National Health Service in England and NHS Wales.The trusts are not trusts in the legal sense but are in effect public sector corporations. Each trust is headed by a board consisting of executive and non-executive directors, and is...
and Aston University
Aston University
Aston University is a "plate glass" campus university situated at Gosta Green, in the city centre of Birmingham, England.Established in 1895 as the Birmingham Municipal Technical School, Aston was granted its Royal Charter as Aston University on 22 April 1966...
.
Frequently touched surfaces typically manufactured with standard materials (i.e., plastic, chrome, aluminum) were replaced with copper alloys. These included a copper alloy set of sink tap handles (60% Cu, 40% Zn) and a ward entrance door push plate (70% Cu, 30% Zn).
Contamination reductions of 90-100% were observed for Staphylococcus aureus
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
, Escherichia coli
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
, Klebsiella pneumoniae
Klebsiella pneumoniae
Klebsiella pneumoniae is a Gram-negative, non-motile, encapsulated, lactose fermenting, facultative anaerobic, rod shaped bacterium found in the normal flora of the mouth, skin, and intestines....
, Acinetobacter baumanii, Enterococcus spp., and Candida albicans
Candida albicans
Candida albicans is a diploid fungus that grows both as yeast and filamentous cells and a causal agent of opportunistic oral and genital infections in humans. Systemic fungal infections including those by C...
on the copper alloy surfaces versus the non-copper standard surfaces. A microorganism reduction of 100% was observed on the hot tap copper alloy handle.
The high degree of clinical performance suggested that copper alloy surfaces may increase the effectiveness of existing infection control practices and may lower the risk of infections acquired in healthcare facilities.
Based on the results of this and other laboratory and clinical studies, St. Francis Private Hospital, a 140-bed facility located in Mullingar, County Westmeath, Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
, decided to become the first hospital in the world to fully specify hygienic copper door handles throughout its facility as part of its infection control program. A full upgrade of all door furniture (i.e., 250 doorsets, incorporating handles, push plates and privacy locks) to antimicrobial copper in the hospital and nursing home commenced in January 2010.
Healthcare architects in the United Kingdom are now specifying antimicrobial copper. Refurbishment projects specifying copper products are anticipated across NHS Trust
NHS Trust
A National Health Service trust provides services on behalf of the National Health Service in England and NHS Wales.The trusts are not trusts in the legal sense but are in effect public sector corporations. Each trust is headed by a board consisting of executive and non-executive directors, and is...
facilities.
Clinical trial in Chile
In ChileChile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
, 70,000 nosocomial infections are reported each year, most commonly from common hospital-borne pathogens such as S. aureus
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
, P. aeruginosa and A.baumanii.
In a 30-week clinical trial at the Hospital del Cobre, in Calama
Calama, Chile
Calama is a city and commune in the Atacama Desert in northern Chile. It is the capital of El Loa Province, part of the Antofagasta Region. Calama is one of the driest cities in the world with average annual precipitation of just . The River Loa, Chile's longest, flows through the city...
, extensive microbial analyses were implemented at the facility’s intensive care unit
Intensive Care Unit
thumb|220px|ICU roomAn intensive-care unit , critical-care unit , intensive-therapy unit/intensive-treatment unit is a specialized department in a hospital that provides intensive-care medicine...
(ICU). Nine hundred ninety 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-the-bed tables were made from copper alloy C70600. Bedrails were cladded 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 (i.e., bed rails by 91%, bed levers by 82%, tray tables by 83%, chair arms by 92%, monitor pen by 49%, and IV poles by 88%).
Average microbial burden counts in rooms with copper touch surfaces were significantly lower than in rooms without copper surfaces. Staphylococci were the most predominant microorganism isolated and copper was effective in reducing the Staphylococci microbial burden. Further studies regarding the clinical implications of copper’s intrinsic ability to reduce microbial burdens in hospitals are being planned.
Clinical trials in Japan
Researchers from the Kitasato UniversityKitasato University
is one of the famous private university in Minato, Tokyo, Japan.The head of the university is located in the Shirokane Campus, neighboring the Kitasato Institute. Its major educational facilities are located in the Sagamihara Campus, located 60 kilometers west of central Tokyo...
School of Medicine conducted antimicrobial studies of S. aureus
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
, E. coli, and P. aeruginosa on various Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
ese copper alloy coins and on copper alloy plates. The microbes were strains from hospital environments. Copper and its nickel-silver, cupronickel
Cupronickel
Cupronickel or copper-nickel or "cupernickel" is an alloy of copper that contains nickel and strengthening elements, such as iron and manganese. Cupronickel is highly resistant to corrosion in seawater, because its electrode potential is adjusted to be neutral with regard to seawater...
, and brass
Brass
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin...
alloys were found to kill the bacteria within a short time. In another experiment, bacterial colonies were investigated on ball point pens made with and without copper alloys. Total bacterial colonies on the copper pens were much lower than on the non-copper pens: 2.1 CFU
Colony-forming unit
In microbiology, colony-forming unit is a measure of viable bacterial or fungal numbers. Unlike direct microscopic counts where all cells, dead and living, are counted, CFU measures viable cells...
versus 47.8 CFU. Staphyloccocus counts on copper ball point pens were also much lower: 0.7 CFUs versus 20.8 CFUs on non-copper pens.
Due to the success of these results, a 2-year clinical trial was conducted to monitor contamination levels of nosocomial bacteria in the dermatology
Dermatology
Dermatology is the branch of medicine dealing with the skin and its diseases, a unique specialty with both medical and surgical aspects. A dermatologist takes care of diseases, in the widest sense, and some cosmetic problems of the skin, scalp, hair, and nails....
ward and neonatal intensive care unit
Intensive Care Unit
thumb|220px|ICU roomAn intensive-care unit , critical-care unit , intensive-therapy unit/intensive-treatment unit is a specialized department in a hospital that provides intensive-care medicine...
(NICU) at Kitasato University
Kitasato University
is one of the famous private university in Minato, Tokyo, Japan.The head of the university is located in the Shirokane Campus, neighboring the Kitasato Institute. Its major educational facilities are located in the Sagamihara Campus, located 60 kilometers west of central Tokyo...
Hospital. The antimicrobial efficacy of copper on floors, sinks, push plates, showerheads and doorknobs was evaluated by comparing bacterial loads on these surfaces and on their non-copper counterparts.
The number of viable Staphylococcus
Staphylococcus
Staphylococcus is a genus of Gram-positive bacteria. Under the microscope they appear round , and form in grape-like clusters....
spp. organisms on surfaces containing copper and its alloy were reduced by half to one-thirtieth of that on control surfaces, depending upon surface humidity and the frequency of contact. Similar definitive findings were also obtained for Pseudomonas aeruginosa
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many...
.
Various metals were evaluated for their antimicrobial efficacies, including copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
alloys, zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
, nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...
, tin
Tin
Tin is a chemical element with the symbol Sn and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to both neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4...
, silver
Silver
Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...
, and gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...
. Antimicrobial efficacies generally followed Lewis acidity values of the various metals. Silver, a prohibitively expensive precious metal
Precious metal
A precious metal is a rare, naturally occurring metallic chemical element of high economic value.Chemically, the precious metals are less reactive than most elements, have high lustre, are softer or more ductile, and have higher melting points than other metals...
, had the highest bactericidal activity; copper came in second. The study also found that contact dermatitis
Contact dermatitis
Contact dermatitis is a term for a skin reaction resulting from exposure to allergens or irritants . Phototoxic dermatitis occurs when the allergen or irritant is activated by sunlight....
allergies rarely occur if copper is used as a hygienic touch material.
The bactericidal activity of copper was also tested against two strains of MRSA and S. aureus
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
in vitro to determine whether copper alloys are effective in preventing the spread of contamination on the touch surface products used in the hospital ward. MRSA and S. aureus counts fell below detection limits within 180 minutes. The results indicated that copper has a strong bactericidal effect against S. aureus, including MRSA.
When a copper plate was situated on a MRSA-infected floor in the dermatology ward around a bed of a MRSA-infected patient, the bacterial count of S. aureus, including MRSA and the other Staphylococcus
Staphylococcus
Staphylococcus is a genus of Gram-positive bacteria. Under the microscope they appear round , and form in grape-like clusters....
on the floor covered with a copper plate was significantly less than on a floor unprotected by copper alloys. These results suggested that the copper plate helped to prevent the spread of MRSA contamination in the hospital.
Clinical Trial in South Africa
Multidrug-resistant and extremely drug resistant Mycobacterium tuberculosisMycobacterium tuberculosis
Mycobacterium tuberculosis is a pathogenic bacterial species in the genus Mycobacterium and the causative agent of most cases of tuberculosis . First discovered in 1882 by Robert Koch, M...
(MTB) is responsible for the spread of tuberculosis
Tuberculosis
Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...
in South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
n hospitals. Test strains of Candida albicans
Candida albicans
Candida albicans is a diploid fungus that grows both as yeast and filamentous cells and a causal agent of opportunistic oral and genital infections in humans. Systemic fungal infections including those by C...
, Pseudomonas aeruginosa
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many...
, Klebsiella pneumoniae
Klebsiella pneumoniae
Klebsiella pneumoniae is a Gram-negative, non-motile, encapsulated, lactose fermenting, facultative anaerobic, rod shaped bacterium found in the normal flora of the mouth, skin, and intestines....
meticillin-resistant Staphylococcus aureus
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
(MRSA), and MTB were isolated from South African patients at a hospital’s intensive care unit in order to establish the minimum in-vitro copper concentrations to produce sterilization
Sterilization (microbiology)
Sterilization is a term referring to any process that eliminates or kills all forms of microbial life, including transmissible agents present on a surface, contained in a fluid, in medication, or in a compound such as biological culture media...
against these microbes and yeast
Yeast
Yeasts are eukaryotic micro-organisms classified in the kingdom Fungi, with 1,500 species currently described estimated to be only 1% of all fungal species. Most reproduce asexually by mitosis, and many do so by an asymmetric division process called budding...
. Acinetobacter baumannii
Acinetobacter baumannii
Acinetobacter baumannii is a species of pathogenic bacteria, referred to as an aerobic gram-negative bacterium, that is resistant to most antibiotics. As a result of its resistance to drug treatment, some estimates state the disease is killing tens of thousands of U.S...
was isolated from a patient in a burn unit and two clinical strains of MTB were collected and tested.
Copper and its alloys demonstrated antimicrobial activities against multiple-antibiotic-resistant nosocomial bacteria and C. albicans
Candida albicans
Candida albicans is a diploid fungus that grows both as yeast and filamentous cells and a causal agent of opportunistic oral and genital infections in humans. Systemic fungal infections including those by C...
isolated from the hospital, whereas stainless steel
Stainless steel
In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....
and PVC
PVC
Polyvinyl chloride is a plastic.PVC may also refer to:*Param Vir Chakra, India's highest military honor*Peripheral venous catheter, a small, flexible tube placed into a peripheral vein in order to administer medication or fluids...
did not. Copper and its alloys showed a marked inhibitory effect (88-98%) on MTB despite the strain’s drug resistance. The researchers concluded that the minimum concentration of copper to be an effective antimicrobial agent is >55% for yeasts and bacteria. Higher concentrations of copper were found to be necessary to inhibit MTB.
Clinical trials in the USA
In the USA, a high degree of statistical significance is needed to provide a convincing argument to U.S. federal government healthcare authorities, such as the Centers for Disease Control and PreventionCenters for Disease Control and Prevention
The Centers for Disease Control and Prevention are a United States federal agency under the Department of Health and Human Services headquartered in Druid Hills, unincorporated DeKalb County, Georgia, in Greater Atlanta...
(CDC), regarding the effectiveness of copper alloys in reducing microbial loads and cross infection in healthcare environments. For this reason, clinical trials at three major US hospitals are currently examining environmental bacterial loads, infection rates, and impacts on cross-contamination in intensive care unit (ICU) rooms retrofitted with copper touch surfaces versus rooms without copper surfaces.
The trials are funded by the U.S. Department of Defense (DOD) under the Telemedicine and Advanced Technologies Research Center (TATRC), a section of the United States Army Medical Research and Materiel Command
United States Army Medical Research and Materiel Command
The United States Army Medical Research and Materiel Command is the United States Army's medical materiel developer, with responsibility for medical research, development, and acquisition and medical logistics management. The USAMRMC's expertise in these critical areas helps establish and maintain...
(USAMRMC). DOD has extraordinary interests in the potential for antimicrobial copper surfaces to reduce hospital-acquired infections because it wants to prevent hospital-acquired infections among thousands of its enlisted armed forces servicemen and servicewomen who have been injured in recent conflicts. TATRC, which funds a Military Infectious Disease Program has been granted funds by the United States Congress
United States Congress
The United States Congress is the bicameral legislature of the federal government of the United States, consisting of the Senate and the House of Representatives. The Congress meets in the United States Capitol in Washington, D.C....
to evaluate the antimicrobial effectiveness of copper, brass and bronze alloys. The studies are coordinated through the Advanced Technology Institute in Charleston, South Carolina.
The clinical studies involve intensive care units (ICUs) at Memorial Sloan-Kettering Cancer Center
Memorial Sloan-Kettering Cancer Center
Memorial Sloan–Kettering Cancer Center is a cancer treatment and research institution founded in 1884 as the New York Cancer Hospital...
in New York City, one of the world’s most prestigious cancer facilities, the Medical University of South Carolina
Medical University of South Carolina
The Medical University of South Carolina opened in Charleston, South Carolina in 1824 as a small private college for the training of physicians. It is one of the oldest continually operating school of medicine in the United States and the oldest in the Deep South...
, and the Ralph H. Johnson VA Medical Center in Charleston
Charleston, South Carolina
Charleston is the second largest city in the U.S. state of South Carolina. It was made the county seat of Charleston County in 1901 when Charleston County was founded. The city's original name was Charles Towne in 1670, and it moved to its present location from a location on the west bank of the...
, South Carolina
South Carolina
South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence...
.
An evaluation of the microbial burden of various objects in the ICU rooms has been documented and is available.
Early results disclosed in 2011 indicate that the coppered rooms demonstrated a 97% reduction in surface pathogens versus the non-coppered rooms. This reduction is the same level achieved by “terminal” cleaning regimens conducted after patients vacate their rooms. Furthermore, of critical importance to health care professionals, the preliminary results indicated that patients in the coppered ICU rooms had a 40.4% lower risk of contracting a hospital acquired infection versus patients in non-coppered ICU rooms. The U.S. Department of Defense investigation contract, which is ongoing, will also evaluate the effectiveness of copper alloy touch surfaces to prevent the transfer of microbes to patients and the transfer of microbes from patients to touch surfaces, as well as the potential efficacy of copper-alloy based components to improve indoor air quality
Indoor air quality
Indoor air quality is a term referring to the air quality within and around buildings and structures, especially as it relates to the health and comfort of building occupants....
.
The latest results from the studies at the three institutions will be developed into a manuscript for publication.
In a separate initiative not funded by the U.S. Department of Defense, clinical trials at an infectious disease outpatient ward consisting of patients with HIV
HIV
Human immunodeficiency virus is a lentivirus that causes acquired immunodeficiency syndrome , a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive...
and other infectious disease
Infectious disease
Infectious diseases, also known as communicable diseases, contagious diseases or transmissible diseases comprise clinically evident illness resulting from the infection, presence and growth of pathogenic biological agents in an individual host organism...
s are being conducted at North Shore University Hospital
North Shore University Hospital
North Shore University Hospital is one of the cornerstones of the North Shore-LIJ Health System, as well as an academic campus for the New York University School of Medicine and the Albert Einstein College of Medicine....
in Manhasset, New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
. An alloy of 90% Cu 10% Ni significantly lowered the microbial burden, primarily Staphylococci, on arm surfaces of phlebotomy
Phlebotomist
Phlebotomists are individuals trained to draw blood from a live person or animal.Phlebotomists collect blood primarily by performing venipuncture and, for collection of minute quantities of blood, fingersticks. Blood may be collected from infants by means of a heel stick...
chairs versus wooden arm surfaces. The median reduction for total bacteria on the copper alloy chairs arms was 90%. Use of the chair with copper arm tops resulted in a 17-fold lower risk of exposure to environmental microbes than when patients used the standard chair. The majority of the samples from the chairs with copper components were below the 500 CFU/ cm2 level believed to represent a risk to hospital patients.
The microbiocidal properties of the copper chair arms were able to confer an ‘antimicrobial halo’ within the general vicinity of the arm top. The microbial burden associated with the wooden side arms of the copper covered chair arms was 70%, lower than those on the control chair. This halo effect may help to help reduce the transfer of pathogenc bacteria.
Similarly, patients and healthcare workers who used chairs with copper trays were subjected to a 15-fold lower risk than the patients using chairs with composite trays. The microbial burden on copper trays was reduced by 88% compared to the composite plastic surface.
USEPA registrations of antimicrobial copper alloy touch surfaces
On February 29, 2008, the United States Environmental Protection AgencyUnited States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...
(EPA) approved the registrations of five different groups of copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
alloys as “antimicrobial
Antimicrobial
An anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...
materials” with public health benefits. The EPA registrations now cover 355 different compositions of copper alloys within these groups. All of the alloys have minimum nominal copper concentrations of 60%. The results of the EPA-supervised antimicrobial studies, demonstrating copper's strong antimicrobial efficacies across a wide range of alloys, were recently published.
These copper alloys are the only solid surface materials to be granted “antimicrobial public health claims” status by EPA. Before these registrations were granted, only antimicrobial gases, liquids, sprays, and concentrated powders, including sterilizers, disinfectants and antiseptics, were registered to make antimicrobial public health claims.
Microbes tested and killed in EPA laboratory tests
The bacteriaBacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
destroyed by copper alloys in the EPA-supervised antimicrobial efficacy tests include:
- Escherichia coliEscherichia coliEscherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
O157:H7, a foodborne pathogen associated with large-scale food recalls. - Methicillin-resistant Staphylococcus aureusMethicillin-resistant Staphylococcus aureusMethicillin-resistant Staphylococcus aureus is a bacterium responsible for several difficult-to-treat infections in humans. It is also called multidrug-resistant Staphylococcus aureus and oxacillin-resistant Staphylococcus aureus...
(MRSA), one of the most virulent strains of antibiotic-resistant bacteria and a common culprit of hospital- and community-acquired infections. - Staphylococcus aureusStaphylococcus aureusStaphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
, the most common of all bacterial staphylococcus (i.e., Staph) infections that cause life-threatening disease, including pneumonia and meningitis. - Enterobacter aerogenesEnterobacter aerogenesEnterobacter aerogenes is a Gram-negative, oxidase negative, catalase positive, citrate positive, indole negative, rod-shaped bacterium....
, a pathogenic bacterium commonly found in hospitals that causes opportunistic skin infections and impacts other body tissues. - Pseudomonas aeruginosaPseudomonas aeruginosaPseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many...
, a bacterium in immunocompromised individuals that infects the pulmonary and urinary tracts, blood and skin. - Vancomycin-resistant EnterococcusVancomycin-Resistant EnterococcusVancomycin-resistant Enterococcus, or vancomycin-resistant enterococci , are bacterial strains of the genus Enterococcus that are resistant to the antibiotic vancomycin. To become VRE, vancomycin-sensitive enterococci typically obtain new DNA in the form of plasmids or transposons which encode...
(VRE), a pathogenic bacterium that is the second leading cause of hospital-acquired infections.
EPA test protocols for copper alloy surfaces
The registrations are based on studies supervised by EPA which found that copper alloys kill more than 99.9% of disease-causing bacteria within just two hours when cleaned regularly (i.e., the metals are free of dirt or grime that may impede the bacteria’s contact with the copper surface).To attain the EPA registrations, the copper alloy groups had to demonstrate strong antimicrobial efficacies according to all of the following rigorous tests:
- Efficacy as a sanitizer: This test protocol measures surviving bacteria on alloy surfaces after two hours.
- Residual self-sanitizing activity: This test protocol measures surviving bacteria on alloy surfaces before and after six wet and dry wear cycles over 24 hours in a standard wear apparatus.
- Continuous reduction of bacterial contaminationContaminationContamination is the presence of a minor and unwanted constituent in material, physical body, natural environment, at a workplace, etc.-Specifics:"Contamination" also has more specific meanings in science:...
: This test protocol measures the number of bacteria that survive on a surface after it has been re-inoculated eight times over a 24-hour period without intermediate cleaning or wiping.
EPA registered antimicrobial copper alloys
The alloy groups tested and approved were C11000, C51000, C70600, C26000, C75200, and C28000.The EPA registration numbers for the six groups of alloys are as follows:
| Group | Copper % | EPA Registration Number |
|---|---|---|
| I | 95.2 to 99.99 | 82012-1 |
| II | 87.3 to 95.0 | 82012-2 |
| III | 78.1 to 87.09 | 82012-3 |
| IV | 68.2 to 77.5 | 82012-4 |
| V | 65.0 to 67.8 | 82012-5 |
| VI | 60.0 to 64.5 | 82012-6 |
Claims granted by EPA in antimicrobial copper alloy registrations
The following claims are now legally permitted when marketing EPA-registered antimicrobial copper alloys in the USA:The registrations state that “antimicrobial copper alloys may be used in hospitals, other healthcare facilities, and various public, commercial and residential buildings.”
Public health claims granted by EPA in antimicrobial copper alloy registrations
The EPA copper alloy registrations were granted “with public health claims,” meaning that they permit manufacturers of copper-based products sold in the U.S. to claim on their labels the ability of copper, brass, and bronze to kill harmful, potentially deadly bacteria.Product stewardship requirements of EPA
As a condition of registration established by EPA, the Copper Development Association (CDA) in the USA is responsible for the product stewardshipProduct stewardship
Product stewardship is a concept whereby environmental protection centers around the product itself, and everyone involved in the lifespan of the product is called upon to take up responsibility to reduce its environmental impact. For manufacturers, this includes planning for, and if necessary,...
of antimicrobial copper alloy products. CDA must ensure that manufacturers promote these products in an appropriate manner. Manufacturers must only promote the proper use and care of these products and must specifically emphasize that the use of these products is a supplement and not a substitute to routine hygienic practices.
EPA mandated that all advertising and marketing materials for antimicrobial copper products contain the following statement:
Antimicrobial copper alloys are intended to provide supplemental antimicrobial action in between routine cleaning of environmental or touch surfaces in healthcare settings, as well as in public buildings and the home. Users must also understand that in order for antimicrobial copper alloys to remain effective, they cannot be coated in any way.
CDA is currently implementing an outreach program through written communications, a product stewardship website, and through a Working Group which meets periodically to expand educational efforts.
More than 100 different potential product applications were cited in the registrations for their potential public health benefits.
Approved products
The following products have been approved for EPA-Registrered antimicrobial copper alloy touch surfaces.Healthcare facilities
The following copper alloy surface products have been granted antimicrobial registration status with public health claims by the EPA for healthcare facilities:- Bedrails, footboardsBed frameA bed frame or bedstead is the part of a bed used to position a mattress or foundation set off the floor. Bed frames are typically made of wood or metal. A bed frame is made up of head, foot, and side rails...
- Over-bed tables
- Bedside tables in hospitals, extended care facilities, senior housing etc. (knobs, pulls, handles; surfaces)
- HandrailHandrailA handrail is a rail that is designed to be grasped by the hand so as to provide stability or support. Handrails are commonly used while ascending or descending stairways and escalators in order to prevent injurious falls. Other applications include bathroom handrails—which help to prevent falls on...
s, (corridor/hallways) ( senior housing), automatic door push plates - Stair rails, handrails, tubular railing, and supports, rail fittings T’s, elbows and brackets
- Bedrails, assistance rails
- ToiletToiletA toilet is a sanitation fixture used primarily for the disposal of human excrement, often found in a small room referred to as a toilet/bathroom/lavatory...
safety rails - Carts: hospital carts (table surfaces, handles, legs), computer carts, record carts, phlebotomyPhlebotomistPhlebotomists are individuals trained to draw blood from a live person or animal.Phlebotomists collect blood primarily by performing venipuncture and, for collection of minute quantities of blood, fingersticks. Blood may be collected from infants by means of a heel stick...
carts, other carts (tables/surfaces, shelving, railings, handles, pulls) - Equipment carts (horizontal surfaces, frames, handles)
- Door push plates, kick plates, mop plates, stretcher plates
- Sinks: spigots, drains, sinks themselves
- Faucet: handles, spigot, drain control lever
- Water fountains: bubbler head, drain strainer, handle
- Alcohol sanitizer dispenser, handle
- Paper towel holdersPaper towel dispenserA paper-towel dispenser is a device that dispenses paper towels in a public restroom when in use. It can either be operated by a handle or automatic....
, facial tissue holders, toilet paper holders - Air Hand dryerHand dryerHand dryers are electric devices found in public washrooms that are used to dry hands. They may either operate with a button or automatically using an infrared sensor.- Costs :...
s, controls and push buttons on air hand dryers - HydrotherapyHydrotherapyHydrotherapy, formerly called hydropathy, involves the use of water for pain-relief and treating illness. The term hydrotherapy itself is synonymous with the term water cure as it was originally marketed by practitioners and promoters in the 19th century...
tanks (whirlpool tanks): shells, covers, headrests, drain fittings (outer surfaces without water contact) - Door handleDoor handleA door handle is an attached mechanism used to open or close a door. In the United States, door handle can refer to any fixed or lever-operated door latch device, including on car doors. The term door knob tends to refer to round operating mechanisms.-History:The first documented invention of the...
s, doorknobs (outer touch surfaces) - Grab barGrab barGrab bars are safety devices designed to enable a person to maintain balance, lessen fatigue while standing, hold some of their weight while maneuvering, or have something to grab onto in case of a slip or fall. A caregiver may use a grab bar to assist with transferring a patient from one place to...
s in bathrooms showers and bathtubs - Panic bars on emergency room doors
- Towel bars
- Showerheads
- CountertopCountertopCountertop usually refers to a horizontal worksurface in kitchens or other food preparation areas, bathrooms or lavatories, and workrooms in general. It is frequently installed upon and supported by cabinets...
s and tabletops (non-food use only) - HingeHingeA hinge is a type of bearing that connects two solid objects, typically allowing only a limited angle of rotation between them. Two objects connected by an ideal hinge rotate relative to each other about a fixed axis of rotation. Hinges may be made of flexible material or of moving components...
s, lockLock (device)A lock is a mechanical or electronic fastening device that is released by a physical object or secret information , or combination of more than one of these....
s, latchesLatch (hardware)A latch is a type of mechanical fastener that is used to join two objects or surfaces together while allowing for the regular or eventual separation of the objects or surfaces....
, and trim - Door stops, door pulls, and protector guards
- Toilet and urinal hardware, levers, push buttons
- Toilet seatToilet seatA toilet seat is a hinged unit consisting of seat and lid which is bolted onto a toilet bowl for a flush toilet. A toilet seat consists of the seat itself, which may be contoured for the user to sit on, and the lid, which covers the toilet when it is not in use.If the toilet is located in a home...
inlay for lifting of seat - Closures
- Vertical locking arms
- Vertical cover guards
- Protection bars
- Light switches, switch plates
- Visitor chairs: armrests, metal frames
- ThermostatThermostatA thermostat is the component of a control system which regulates the temperature of a system so that the system's temperature is maintained near a desired setpoint temperature. The thermostat does this by switching heating or cooling devices on or off, or regulating the flow of a heat transfer...
covers, control knobs and wheels - TelephoneTelephoneThe telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...
handsets and surfaces (housings), keypad - Kitchen surfaces (non-food contact only): table tops, counter tops, handles (microwave, refrigerator, stove), cabinet doors, cabinet hinges, pulls, backsplash, hoods, control knobs (appliances, fans)
- Floor tiles
- Ceiling tiles (non-porous)
- Wall tiles
- Instrument handles: Medical equipment knobs, pulls and handles for:
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- Drug delivery systems
- Monitoring systems
- Hospital beds
- Office equipment
- Operating room equipment
- Stands and fixtures
- Types of knobs: e.g. prong, fluted, knurled, push/pull, T-handle, tapered, and ball knobs
- Intravenous (IV) poles, bases, hangers, clips
- Trays (instruments, non-food contact)
- BedpanBedpanA bedpan or bed pan is an object used for the toileting of a bedridden patient in a health care facility, usually made of a metal, glass, or plastic receptacle. A bed pan can be used for both urinary and fecal discharge. Many diseases can confine a patient to bed, necessitating the use of bedpans,...
s - Walkers, wheelchairWheelchairA wheelchair is a chair with wheels, designed to be a replacement for walking. The device comes in variations where it is propelled by motors or by the seated occupant turning the rear wheels by hand. Often there are handles behind the seat for someone else to do the pushing...
handles, and tubular components - Computer keyboardComputer keyboardIn computing, a keyboard is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches...
s: keys, housings, computer mouse surfaces - Exercise and rehabilitation equipment, handles, bars
- Physical therapy equipment: physical therapy tables, treatment chairs and portable taping tables
- ChairChairA chair is a stable, raised surface used to sit on, commonly for use by one person. Chairs are most often supported by four legs and have a back; however, a chair can have three legs or could have a different shape depending on the criteria of the chair specifications. A chair without a back or...
s (shower chairs, patient chairs, visitor chairs): rails, backs, legs, seats - Lighting products: X-ray illuminators, operating rooms, patient examination rooms, surgical suites, and reading lamps for hospital rooms and assisted living facilities etc. Components can include bases, arms, housings, handles, hinges
- Headwall systems: the unit themselves, outlet covers, knobs and dials, lighting units (lamp housings and adjustable arms), CRT monitors with rotating knobs and levers and adjustments. Baskets, monitor housings, knobs, baskets, tables, IV poles
- Critical care cart: Table top, drawer, drawer pull, lock, copper wire baskets for storage of equipment and charts.
- Bedside lavatory: sink, faucet, handles, drawer pulls, toilet seat, toilet seat cover, toilet handle, door and cabinet facings, counter tops
- Medical records: Chart holders, clipboards, filing systems
- Storage shelving: wire shelving etc. for medical supplies
- Grab handles on privacy curtains
- Lids of laundry hampers, trash canisters, and other containers
- Bedside pitchers
- ClosetClosetA closet is a small and enclosed space, a cabinet, or a cupboard in a house or building used for general storage or hanging clothes. A closet for food storage is usually referred to as a pantry...
rods and hangers - TelevisionTelevisionTelevision is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...
controls: knobs, buttons, remote - Monitor (television, computer, etc.) housing
- Cup holder
- Toothbrush holder
- Soap holder
- Magazine rack
- Signage
- Coat rack and hooks
- Shower curtain rings
- RadiatorRadiatorRadiators are heat exchangers used to transfer thermal energy from one medium to another for the purpose of cooling and heating. The majority of radiators are constructed to function in automobiles, buildings, and electronics...
cover - BraceletBraceletA bracelet is an article of jewelry which is worn around the wrist. Bracelets can be manufactured from metal, leather, cloth, plastic or other materials and sometimes contain jewels, rocks, wood, and/or shells...
s - PenPenA pen is a device used to apply ink to a surface, usually paper, for writing or drawing. Historically, reed pens, quill pens, and dip pens were used, with a nib of some sort to be dipped in the ink. Ruling pens allow precise adjustment of line width, and still find a few specialized uses, but...
s - Badge clips
- Name tags
- Patient gown snaps
- Window sills, pulls and locks
- Electrical wallplates
Public community facilities (including various public and commercial buildings)
The following copper alloy surface products have been granted antimicrobial registration status with public health claims by EPA for public community facilities:- Shopping cart handles, child seats, handrails
- Cash registers: housing, keypads
- automated teller machineAutomated teller machineAn automated teller machine or automatic teller machine, also known as a Cashpoint , cash machine or sometimes a hole in the wall in British English, is a computerised telecommunications device that provides the clients of a financial institution with access to financial transactions in a public...
s: keys, housing - Gym/Health club lockers, locker handles, locker shelving, trainers’ tables
- Ice and water dispensers (outer surfaces without water contact)
- Elevator: handrail, control panel, buttons, interior walls, floor tiles, exterior call button plate
- Paper towel dispensers. Housing itself, (turn) handle, (push) handle
- Soap holder
- Soap dispenser (wall mounted): push bar and dispenser itself
- Soap dispenser (sitting on counter): dispenser housing itself, push mechanism
- Toilet paper dispenser (housing)
- Windows (crank), Locking mechanism, pull handles
- Window treatments (cord pulls), Venetian blinds (wands, cord pulls)
- Jalousie Windows (crank)
- Casement (cranks, levers, hinges)
- Single and double-hung windows (locks and pulls)
- Light switches, switch plates
- Lids of laundry hampers, trash canisters, and other containers
- Magazine rack
- Signage
- Coat rack and hooks
- Shower curtain rings
- Radiator cover
- Bracelets
- Badge clips
- Name tags
- Vending machines (non-food contact only)
- Window sills
- Electrical wallplates
- Clip boards
- Office supplies: paper clips, staplers, tape dispensers
Residential buildings
Residential buildings include homes, apartments, apartment buildings and other kinds of residences. The following copper alloy surface products have been granted antimicrobial registration status with public health claims by EPA for residential buildings:- Kitchen surfaces (non-food contact only): table tops, counter tops, handles (microwave, refrigerator, stove), cabinet doors, cabinet hinges, pulls, backsplash, hoods, control knobs (appliances, fans)
- Bedrails, footboards
- Handrails
- Stair rails
- Door push plates
- Sinks: spigots, drains, sinks themselves
- Faucet: handles, spigot, drain control lever
- Paper towel holders, facial tissue holders, toilet paper holders
- Door handles, doorknobs (outer touch surfaces)
- Grab bars in bathrooms showers and bathtubs
- Towel bars
- Showerheads
- Countertops and tabletops
- Hinges, locks, latches, and trim
- Door stops, door pulls, and protector guards
- Toilet and urinal hardware, levers, push buttons
- Toilet seat inlay for lifting of seat
- Light switches, switch plates
- Thermostat covers, control knobs and wheels
- Telephone handsets and surfaces (housings), keypad
- Floor tiles
- Ceiling tiles (non-porous)
- Wall tiles
- Computer keyboards: keys, housings, computer mouse surfaces
- Exercise equipment, handles, bars
- Windows (crank), Locking mechanism, pull handles
- Window treatments (cord pulls), Venetian blinds (wands, cord pulls)
- Jalousie windows (crank)
- Casement (cranks, levers, hinges)
- Single and double-hung windows (locks and pulls)
- Television control knobs and buttons
- Lids of laundry hampers, trash canisters, and other containers
- Bedside pitchers
- Closet rods and hangers
- Television remote
- Cup holder
- Soap holder
- Magazine rack
- Coat rack and hooks
- Shower curtain rings
- Radiator cover
- Window sills
- Electrical wallplates
- Baby cribs: rails, fittings, brackets, supports
- Bowl stands
- Office supplies: paper clips, staplers, tape dispensers
- Monitor (television, computer, etc.) housing
Mass transit facilities
The following copper alloy surface products have been granted antimicrobial registration status with public health claims by EPA for mass transit facilities:- Handrails
- Stair rails, tubular railing, and supports; elbows and brackets
- Door push plates, kick plates
- Door handles, door knobs (outer touch surfaces)
- Grab bars and handles
- Tiles: wall, floor, ceiling (non-porous)
- Chairs and benches: rails, backs, legs, seats
- Window sills, pulls, and handles
- Signage
- Vending machines (non-food contact only)
Other EPA-approved products
The following copper alloy surface products have been granted antimicrobial registration status with public health claims by EPA for various products:- Play area equipment (outdoor): bars, handles, chains, push plates, handrails, stair rails and risers, wheels, knobs, flooring
- Chapel pews
- Eye glass frames and protective eye wear
- Pens
- Combs
- Ashtrays
The EPA warranty statement
The EPA warranty statement is worded as follows:Note: With the exception of the product name and the percentage of active ingredient, the EPA-approved Master Labels for the six groups of registered alloys are identical.
See also
- Antimicrobial properties of copperAntimicrobial properties of copperCopper and its alloys are natural antimicrobial materials. Ancient civilizations exploited the antimicrobial properties of copper long before the concept of microbes became understood in the nineteenth century...
- Brass
- Copper alloys in aquacultureCopper alloys in aquacultureRecently, copper alloys have become important netting materials in aquaculture . Various other materials including nylon, polyester, polypropylene, polyethylene, plastic-coated welded wire, rubber, patented twine products , and galvanized steel are also used for netting in aquaculture fish...