{"id":2949,"date":"2021-03-19T09:09:14","date_gmt":"2021-03-19T07:09:14","guid":{"rendered":"https:\/\/halco.gr\/?p=2949"},"modified":"2021-04-13T14:01:46","modified_gmt":"2021-04-13T11:01:46","slug":"the-role-of-antimicrobial-copper-surfaces-in-reducing-healthcare-associated-infections","status":"publish","type":"post","link":"https:\/\/halco.gr\/el\/the-role-of-antimicrobial-copper-surfaces-in-reducing-healthcare-associated-infections\/","title":{"rendered":"The Role of Antimicrobial Copper Surfaces in Reducing Healthcare-associated Infections"},"content":{"rendered":"
Recent work investigating the antimicrobial characteristics of copper has led to a re-evaluation of the role of this essential metal in healthcare.
\nWhile ancient civilisations used copper for its health benefits it seems its usefulness has been forgotten. The requirement for evidence-based
\ninterventions for infection control has been the driver behind recent scientific assessments of the benefits of copper. Ten years of laboratory
\nresearch has led to clinical trials confirming a very significant and continuous reduction in environmental bioburden in a number of healthcare\u00a0settings globally. The newest and most comprehensive clinical research has now reported an impressive 40 % reduction in healthcare-associated\u00a0infections in intensive care units (ICUs) where copper was incorporated in key touch surfaces. The deployment of copper touch surfaces\u00a0should be considered as an additional infection control measure to reduce care costs and improve bed availability and patient outcomes.
\n<\/span><\/h6>\n

 <\/p>\n

Historical Context<\/strong><\/h5>\n

That copper has beneficial effects for humans has been known for at
\nleast 4,000 years. The use of copper for drinking water containers\u00a0to ensure potability and the application of the powdered metal to\u00a0wounds for disinfection, are reported in ancient Egypt. The Aztecs\u00a0used copper to treat various skin diseases. Hippocrates, the father of\u00a0medicine (460\u2013380 BCE), recommended the use of copper for leg\u00a0ulcers related to varicose veins. In France, during the three cholera\u00a0epidemics around 1850, it was observed that workers in copper\u00a0foundries were not affected by the disease.<\/p>\n

More recently, in 1970, the American College of Chest Physicians
\npublished on the \u2018antibacterial action of copper\u2019. They showed that\u00a0the use of copper in large reservoir nebulisers for respiratory therapy
\nresulted in the contents remaining sterile.1 More pertinently, in 1983,\u00a0a hospital study in Pennsylvania showed copper\u2019s effectiveness in\u00a0lowering the Escherichia Coli count on brass door knobs.2<\/p>\n

 <\/p>\n

The Healthcare-associated Infection Problem<\/strong><\/h5>\n

During the subsequent decades, the major concern within the medical
\ncommunity has been healthcare-associated infections (HCAIs), or
\n\u2018nosocomial\u2019 infections. This year\u2019s report from the World Health
\nOrganization (WHO) notes how difficult it is to gather reliable and
\ncomparable HCAI evidence globally, or even nationally. But they are\u00a0able to conclude that hundreds of millions of patients are affected by\u00a0them around the world.3<\/p>\n

Only receiving public attention when a family member suffers or\u00a0when there are outbreaks, HCAIs are a very real endemic, ongoing\u00a0problem and one that no institution or country can claim to\u00a0have solved, despite many efforts. The statistics are harrowing.\u00a0The European Centre for Disease Prevention and Control (ECDC)\u00a0indicated HCAI levels in Europe as 7.1 % in 2008.4 This equates to\u00a0over four million patients being affected each year. The estimated\u00a0incidence rate in the US was 4.5 % in 2002, corresponding to\u00a01.7 million affected patients.5<\/p>\n

Infections in intensive care units (ICUs) can be as high as 51 %, most\u00a0of these being healthcare associated. Furthermore, the longer\u00a0patients stay in an ICU, the more at risk they become of acquiring\u00a0an infection.3<\/p>\n

The measures taken towards reducing microbe transportation\u00a0through frequently touched surfaces started in the last decade with\u00a0the WHO \u2018Clean Care is Safer Care\u2019 campaign. In many national\u00a0healthcare systems, specific guidelines were given to healthcare\u00a0professionals in order to raise awareness and help combat\u00a0nosocomial infections.<\/p>\n

In 2001 in the UK, the \u2018EPIC Project: Developing National\u00a0Evidence-based Guidelines for Preventing Healthcare associated\u00a0Infections\u2019 among other good practices, points out touch surfaces as\u00a0one of the major components of microbial concentration and transfer.6<\/p>\n

 <\/p>\n

Copper in Laboratory Studies<\/strong><\/h5>\n

In 2000, the early laboratory studies from the University of\u00a0Southampton indicated that copper cast alloys (e.g. brass and\u00a0bronze) were able to reduce E.Coli O157 cross-contamination during\u00a0food-handling procedures. The research showed that although\u00a0stainless steel may appear clean, bacteria can survive on these\u00a0surfaces for considerable periods of time. In comparison, survival on\u00a0many copper alloys is limited to just a few hours or even minutes.\u00a0Due to the intrinsic characteristics of copper alloys, i.e. being\u00a0homogenous and solid, wear resistant and durable, complete lifetime\u00a0antimicrobial efficacy could be expected. These may then be utilised\u00a0in facilities where bacterial contamination cannot be tolerated.7<\/p>\n

One fundamental consideration in the early laboratory studies was
\nwhich test of efficacy to employ. The only existing test for a solid\u00a0material had been developed in Japan (JIS Z 2801) but stipulated\u00a0conditions wholly different to a typical indoor environment, i.e. 35 \u00baC\u00a0and in a relative humidity of 100 %. Copper alloys were shown to\u00a0easily \u2018pass\u2019 this test, which required contact for 24 hours.\u00a0More appropriate standards were those based upon liquid disinfectants,\u00a0like the current EN 1276, which used a more typical 20 \u00baC and allowed\u00a0the inoculum to dry in sterile air. The Southampton team developed a\u00a0modified version of this and was able to measure efficacy at specified\u00a0times in order to obtain a kill rate curve.<\/p>\n

This test protocol has\u00a0subsequently been verified in a number of other laboratories worldwide.\u00a0The test is versatile and sensitive enough to allow comparison of\u00a0different inoculum levels: from the disinfectant-based standard\u00a0of 10 million colony-forming units (CFU) down to more typical hospital\u00a0contamination levels such as 1,000 CFU or less. It has also been used\u00a0to show efficacy at refrigeration temperatures. Comparative work
\nusing this test protocol (under typical indoor conditions) shows that
\nsilver-containing composites, like the stainless steel control, showed
\nno efficacy.8<\/p>\n

Subsequently, many papers have been published from numerous
\nresearchers expanding the understanding of the antimicrobial activity of
\ncopper alloys.9,10,11 As a simple comparison, against an antibiotic,
\nco-workers compared a copper alloy (CuZn37) with Aminoglycocide in a
\nzone of inhibition test, showing comparable efficacy.12<\/p>\n

In 2008, the US Environmental Protection Agency (EPA), following
\nrigorous independent testing based upon the Southampton-developed
\nprotocol, permitted the registration of nearly 300 copper alloys.13 This
\nallows public health claims to be made for the alloys under the terms of
\nthe registration, a first for solid materials.<\/p>\n

Most recently, further developments of the laboratory test protocols
\nhave led to published work showing that efficacy on a dry surface can
\nbe as short as two minutes.14 The Southampton team also published
\nwork showing that even high inoculum levels of MRSA and VRE in
\ndroplet-like contamination events were eradicated in less than 10
\nminutes.15,16 These have both been driven by attempts to make the
\nlaboratory tests similar to real life conditions.<\/p>\n

Broad Spectrum Efficacy<\/strong><\/h5>\n

In general, antimicrobial copper alloys are effective against bacteria,
\nviruses, fungi and moulds, including these significant pathogens\u00a0(see Table 1).<\/p>\n

Mechanisms<\/strong><\/h5>\n

Work is ongoing on the mechanism14\u201316 by which copper exerts its
\neffect, but it is clear that the attack is a complex interaction rather than
\njust one process interrupter. The speed at which the reactions occur
\ncomplicates the research and a number of modes of action have\u00a0been identified. Theories include membrane puncture and leakage,
\ndisturbance of osmotic balance and generation of free radicals\u00a0causing oxidative stress. At some stage the cell DNA is completely\u00a0destroyed, indicating that transfer of antimicrobial resistance should\u00a0not be a factor of concern.<\/p>\n

Clinical Trials<\/strong><\/h5>\n

The first qualitative clinical trial was performed at Kitasato University
\nHospital in Japan in 2005.17 However, a fully quantitative trial was
\ninitiated in 2007 on a 20-bed medical ward at Selly Oak Hospital in
\nBirmingham, UK.<\/p>\n

\u2018Hot spot\u2019 touch surfaces were identified by a team of clinicians and
\nmicrobiologists. The components included dressings trolleys, light
\nswitches, taps, door and equipment handles, push plates, grab rails and
\nover-bed tables. These were upgraded to copper or copper alloy\u00a0and placed on the ward over the course of six months. Once installed,\u00a0the clinical assessment ran for three months and was able to report\u00a090\u2013100 % reductions in contamination on copper surfaces compared\u00a0with controls. Standard cleaning procedures and products were used\u00a0throughout the trial.18<\/p>\n

Subsequently, a clinical trial in ICU rooms at Calama Hospital in Chile
\nreported similar reductions. Notably, this region has regular daytime
\nhumidity levels of just 6 %.19<\/p>\n

In a recent out-patient study, not only was the reduction in\u00a0microbial burden confirmed but a \u2018halo\u2019 effect was observed: reduced
\ncontamination in the immediate vicinity of the copper surfaces. The
\ncopper surfaces were calculated to reduce the risk of exposure to
\nenvironmental microbes by a factor of 17.20<\/p>\n

Infection Rates<\/strong><\/h5>\n

In a three-centre clinical trial (see Figure 1) completed in June 2011,\u00a0the first proof of improved patient outcomes was reported. The trial\u00a0initially carried out an observational assessment of key touch surfaces\u00a0and contamination levels in an ICU environment, identifying which\u00a0room components to upgrade to copper alloys.<\/p>\n

Table 1: Antimicrobial Copper Alloys are Effective
\nAgainst These Pathogens
\nAcinetobacter baumannii Klebsiella pneumoniae
\nAdenovirus Legionella pneumophila
\nAspergillus niger Listeria monocytogenes
\nCandida albicans Methicillin-resistant Staphylococcus
\naureus (MRSA, including E-MRSA
\nand methicillin-sensitive
\nS. aureus [MSSA])
\nCampylobacter jejuni Poliovirus
\nClostridium difficile (including spores) Pseudomonas aeruginosa
\nEnterobacter aerogenes Salmonella enteritidis
\nEscherichia coli O157:H7 S. aureus
\nHelicobacter pylori Tubercle bacillus
\nInfluenza A (H1N1) Vancomycin-resistant
\nenterococcus (VRE)<\/p>\n

The Role of Antimicrobial Copper Surfaces in Reducing Healthcare-associated Infections<\/strong><\/h5>\n

 <\/p>\n

Just six key components were selected and re-engineered to take a\u00a0copper or copper alloy surface. This included the bed rails, visitor\u00a0chair arms and nurse call-buttons. After upgrade, reduction in\u00a0contamination levels on these items was verified to be 97 % (see\u00a0Figure 2) \u2013 confirming the results from Selly Oak. Finally, after three\u00a0and a half years, the interim result reported at the 1st WHO\u00a0International Conference on Prevention and Infection Control (ICPIC)\u00a0indicated a reduction in HCAIs of 40 % for patients in the copper\u00a0rooms compared with those in the non-copper rooms. For patients in\u00a0a copper room with all six copper items present throughout their stay,\u00a0the reduction was nearly 70 %.21<\/p>\n

Future Activities<\/strong><\/h5>\n

Up until now, all research and applications appear to show great
\npotential regarding the effectiveness of antimicrobial copper alloys
\nagainst bacteria and other pathogenic organisms.<\/p>\n

Further to the scientific and clinical research results, manufacturers
\nhave also shown great interest in producing objects that are used
\nfrequently in high nosocomial potential areas (e.g. ICU, medical\u00a0wards, etc.). However, implementation outside hospital areas, where\u00a0microbial flora are at high levels, also worries public health planners.<\/p>\n

In Laval, France, the brand new Center Inter-Generational Multi\u00a0Accueil (CIGMA)22 \u2013 a nursery for 35 infants and a 60-bed care home\u00a0for dependent elderly people \u2013 has deployed copper alloys on all\u00a0handrails and door handles. In Tokyo, Japan, the Mejiro Daycare\u00a0Center for Children fitted copper sinks and handrails, as well as other\u00a0touch surfaces.23<\/p>\n

In Athens, Greece, a large private elementary school with 2,500 students
\nchanged all the handrails, door handles and push plates to those made
\nfrom copper alloy (Cu 64 %, Zn 36 %). The first results showed 90\u2013100 %
\nless contamination than on standard, non-copper surfaces.24<\/p>\n

In another application area, transport, the Santiago Metro system\u00a0in Chile has installed copper alloy handrails at one new station.25
\nSubsequently, the Metro has signed contracts to fit brass handrails on\u00a0two new lines under construction \u2013 some 30 stations.<\/p>\n

Economics<\/strong><\/h5>\n

The total cost of copper or copper alloy objects is a combination of raw
\nmaterial and manufacturing time. Many copper alloys are still used
\nwidely in industry because they can be fabricated into complex parts
\neasily and quickly (e.g. taps and lock mechanisms). This means that
\ncopper alloy components will become cost-effective when product
\nvolumes are economic even if prototypes carry a premium.<\/p>\n

Furthermore, because these components are generally straightforward
\nto install, they will be more cost-effective than many high-tech
\npropositions. Installing during a typical refurbishment project, when
\nsuch common equipment would be refitted anyway, requires few special skills and is therefore broadly cost neutral. These items will\u00a0also likely have a 30-year minimum lifetime.<\/p>\n

Due to the antimicrobial efficacy, the cost of replacing and\u00a0installing copper alloy components cannot be compared to the cost\u00a0of objects made from other types of material (stainless steel,\u00a0plastic, etc.). Rather, it is the value of the benefit of copper that\u00a0should be assessed. Targeted installation of copper clearly results\u00a0in a decrease in environmental bioburden. Now the link has\u00a0been established between this and infection rates: Dr Schmidt\u2019s\u00a0conservative assessment indicates a 40 % reduction in ICU-acquired\u00a0infections, with the potential for a 70 % reduction. This should\u00a0lead to a reduction in care costs, better bed availability and an
\nimprovement in patient outcomes. When, as should result, we\u00a0are able to decrease antibiotics usage, we have a further a\u00a0benefit of incalculable value. In times when multi-resistant bacteria\u00a0are increasing and antibiotics could have run their course, the\u00a0antimicrobial copper era may have dawned.<\/p>\n

1. Deane RS, Mills EL, Hamel AJ, Antimicrobial action of copper\u00a0in respiratory therapy apparatus, Chest, 1970;58(4):373\u20137
\n2. Kuhn PJ, Doorknobs: a source of nosocomial infection?,\u00a0Diagnostic Medicine, 1983;62\u20133.
\n3. WHO, Report on the Burden of Endemic Healthcare-Associated Infection Worldwide, 2011.
\n4. European Centre for Disease Prevention and Control (ECDC),\u00a0Annual Epidemiological Report, 2008.
\n5. Klevens RM, Edwards JR, Richards CL Jr, et al., Estimating\u00a0health care-associated infections and deaths in U.S.\u00a0hospitals, 2002, Public Health Rep, 2007;122:160\u20136.
\n6. EPIC, Guidelines for preventing healthcare-associated\u00a0infections, J Hosp Infect, 2001;47(Suppl.):S1.
\n7. Noyce JO, Michels H, Keevil CW, Use of copper cast alloys to\u00a0control Escherichia coli O157 cross-contamination during\u00a0food processing, Appl Environ Microbiol, 2006:72;4239\u201344.
\n8. Michels HT, Noyce JO, Keevil CW, Effects of temperature and\u00a0humidity on the efficacy of methicillin-resistant\u00a0Staphylococcus aureus challenged antimicrobial materials\u00a0containing silver and copper, Lett Appl Microbiol,
\n2009;49(2):191\u20135.
\n9. Noyce JO, Michels H, Keevil CW, Inactivation of influenza A\u00a0virus on copper versus stainless steel surfaces, Appl Environ\u00a0Microbiol, 2007;73(8):2748\u201350.
\n10. Weaver L, Michels HT, Keevil CW, Survival of Clostridium difficile\u00a0on copper and steel: futuristic options for hospital hygiene, J\u00a0Hosp Infect, 2008;68:145\u201351.
\n11. Wheeldon LJ, Worthington T, Lambert PA, et al., Antimicrobial
\nefficacy of copper surfaces against spores and vegetative\u00a0cells of Clostridium difficile: the germination theory,\u00a0J Antimicrob Chemother, 2008;62:522\u20135.
\n12. Kouskouni E, Tsouma I, Patikas I, et al., Antimicrobial activity\u00a0of copper alloys compared to aminoglycosides against\u00a0multidrug resistant bacteria, Abstract 3597, Presented at: the\u00a0ECCMID-ICC, 7\u201310 May 2011.
\n13. Michels HT, Anderson DG, Antimicrobial regulatory efficacy\u00a0testing of solid copper alloy surfaces in the USA,\u00a0Metal Ions Biol Med, 2008;10:185\u201390.
\n14. Santo CE, Ee WL, Elowsky CG, et al., Bacterial killing by dry\u00a0metallic copper surfaces, Appl Environ Microbiol,\u00a02011;77(3):794\u2013802.
\n15. Keevil CW, Warnes SL, New insights into the antimicrobial
\nmechanisms of copper touch surfaces, BMC Proceedings,\u00a02011;5(Suppl. 6):P39.
\n16. Warnes SL, Keevil CW, Mechanism of copper surface toxicity\u00a0in vancomycin-resistant enterococci following \u2018wet\u2019 or \u2018dry\u2019\u00a0contact, Appl Environ Microbiol, 2011;[Epub ahead of print].
\n17. Sasahara T, Niiyama N, Ueno M, Use of copper and its alloys\u00a0to reduce bacterial contamination in hospitals (invited\u00a0lecture), J JRICu, 2007;46(1);12\u20136.
\n18. Casey A, Adams D, Karpanen TJ, et al., Role of copper in\u00a0reducing hospital environment contamination, J Hosp Infect,\u00a02010;74:72\u20137.
\n19. Prado V, Duran C, Crestto M, et al., Effectiveness of copper\u00a0contact surfaces in reducing the microbial burden (MB) in the\u00a0intensive care unit (ICU) of Hospital del Cobre, Calama, Chile,\u00a0Presented at: the 14th International Conference on Infectious\u00a0Diseases, Poster 56.044, Miami, 11 March 2011.
\n20. Hirsch BE, Attaway H, Nadan R, et al., Copper Surfaces\u00a0Reduce the Microbial Burden in an Out-Patient Infectious\u00a0Disease Practice, Poster 458, Presented at: the 50th\u00a0Interscience Conference on Antimicrobial Agents in\u00a0Chemotherapy (ICAAC), Boston, MA, 12\u201315 September 2010.
\n21. Schmidt MG, Copper Touch Surface Initiative Microbiology\u00a0and Immunology, Medical University of South Carolina,\u00a0Charleston, USA, BMC Proceedings, 2011;5(Suppl. 6):O53
\n22. Copper Development Association, Pioneering eco care home\u00a0specifies antimicrobial copper \u2013 Laval, France,\u00a0PR 799, 2011.
\n23. Copper Development Association, Antimicrobial Copper\u00a0to Protect Children against Infections \u2013 Tokyo, Japan,\u00a0PR 797, 2011.
\n24. Efstathiou P, Koustoni E, Tseroni M, et al., Elementary\u00a0schools in Athens \u2013 application of antimicrobial copper,\u00a0Presented at: XVI Congreso Nacional y V Internacional de la\u00a0Sociedad Espa\u00f1ola de Medicina Preventiva alud Publica e\u00a0Higiene, (SEMPSPH), 25\u201327 May 2011.
\n25. Financial Report, Codelco, January \u2013 March 2011.<\/p>","protected":false},"excerpt":{"rendered":"

Recent work investigating the antimicrobial characteristics of copper has led to a re-evaluation of the role of this essential metal in healthcare. While ancient civilisations used copper for its health benefits it seems its usefulness has been forgotten. The requirement for evidence-based interventions for infection control has been the driver behind recent scientific assessments of … Continue reading<\/a><\/p>","protected":false},"author":1,"featured_media":2953,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[12],"tags":[],"_links":{"self":[{"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/posts\/2949"}],"collection":[{"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/comments?post=2949"}],"version-history":[{"count":3,"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/posts\/2949\/revisions"}],"predecessor-version":[{"id":3667,"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/posts\/2949\/revisions\/3667"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/media\/2953"}],"wp:attachment":[{"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/media?parent=2949"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/categories?post=2949"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/halco.gr\/el\/wp-json\/wp\/v2\/tags?post=2949"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}