Franz Lorenschitz of Allgood explores the inherent differences between antimicrobial copper and antimicrobial coatings and how long-term durable solutions can significantly reduce the spread of healthcare associated infections
Within healthcare environments there is an intense focus on cleaning and hygiene standards as part of the overall infection prevention and control strategy.
Hospitals and care homes implement various tactics, including stringent handwashing procedures using soap, sanitiser and alcohol solutions.
Diligence is maintained in every aspect of day-to-day tasks to maintain a clean and germ-free environment for residents, patients, and staff.
Despite these measures, healthcare associated infections (HCAIs) remain a serious issue, with 300,000 patients a year in England acquiring some form of infection while in the care of the NHS.
Due to the dynamic nature of the healthcare environment, and the patients who occupy them, it is very hard to completely eradicate contamination and the spread of bacteria and viruses. However, there are additional measures that can be taken to mitigate the risk.
One such measure, which is proving especially popular in healthcare environments, is the use of ironmongery with antimicrobial properties.
As surface contact is one of the predominant vectors by which contamination and HCAIs are spread; specifying ‘high touch’ antimicrobial ironmongery items such as pull handles, cabinet, and lever handles, push plates, and WC turns can be a very-effective way of reducing the risk.
However, there are some very-important distinctions and comparisons to make between ironmongery that has intrinsic antimicrobial qualities and those that merely have an antimicrobial coating.
Antimicrobial copper is the most-effective touch surface material in the fight against pathogenic microbes, eradicating 99.9% of bacteria that cause HCAIs within two hours of contact.
Both antimicrobial copper and copper alloys that contain more than 60% copper have been globally recognised in laboratory and clinical trials for their antimicrobial qualities.
What can be confusing for those within the healthcare sector who are specifying, or thinking of opting for, antimicrobial ironmongery is the presence of products that are coated claiming antimicrobial properties in a laboratory setting.
Due to the dynamic nature of the healthcare environment, and the patients who occupy them, it is very hard to completely eradicate contamination and the spread of bacteria and viruses. However, there are additional measures that can be taken to mitigate the risk
Whereas the potency of protection against the spread of HCAIs in an antimicrobial copper product arises from its elemental make-up, those that are coated provide less of a guarantee of both short-term efficacy and long-term effectiveness.
In 2008, the Organisation for Economic Co-operation and Development (OECD) reported on work into this area through its committee of global experts.
They proposed a three-tier approach to testing antimicrobial materials: Tier 1, an indicator or proof of principle test; Tier 2, simulated real life tests (closely representing field conditions); and Tier 3, controlled field trials.
A graph demonstrating the effectiveness of antimicrobial coatings and antimicrobial copper in typical indoor conditions
While work is ongoing at the British Standards Institute to establish a suitable Tier 2 standardised method for the determination of antimicrobial efficacy simulating relatively-dry touch conditions, a simple Tier 1 ‘proof of principle’ test has persisted in the market.
The method, in BS EN ISO 22196 and the Japanese Industrial Standard on which it is predicated (JIS Z 2801), is conducted at elevated temperature (35oC) and humidity (>95%) not representative of indoor conditions, and over a period of 24 hours.
When developed in the 1950s, it was argued that this test would give the bacteria their best chance of survival – under conditions similar to those experienced in vivo, the preferred environment for bacterial growth.
This test has been used as the basis for much of the marketing information associated with treated plastics and coatings that operate at perhaps 20oC and 50% humidity.
Hospitals and medical facilities strive to create the healthiest and most-hygienic environments possible. Consequently, in order to limit the spread of dangerous bacteria and disease, many facilities are now turning to antimicrobial copper to stop the spread of infections
Before 2008, and through dialogue with the US Environmental Protection Agency (EPA) along with a consideration of OECD recommendations, experts in the infection control community established a set of three Tier Two methods to assess the efficacy of copper alloys.
Under these (effectively Tier Two) conditions, efficacy is tested in a tighter time window, which gives the antimicrobial product less time to eradicate microbes.
The humidity, temperature and exposure levels have also been tailored to provide a closer simulation of how the product performs in a real-life medical setting.
In 2008, following extensive testing, the EPA granted approval for copper alloys to make public health claims, a necessary step in the regulation process.
As part of the EPA registration, the copper industry was required to establish a stewardship scheme to ensure correct promotion and use of copper alloys.
Under simulated dry-touch conditions, copper and copper alloys have subsequently proven their efficacy.
In a live, televised laboratory trial conducted by Professor Bill Keevil from the University of Southampton, antimicrobial copper was shown to eradicate 10,000,000 bacteria of methicillin-resistant Staphylococcus aureus (MRSA) in just eight minutes.
Furthermore, an academic paper based on this research, published in the Journal of Applied and Environmental Microbiology, concluded: “This study is the first to show very-rapid killing of fingertip contamination of MRSA and MSSA on copper alloys, and the authors propose that incorporation of copper alloy surfaces may help to reduce the transmission of MRSA and MSSA from contaminated surfaces”.
To date, no coating products have been awarded EPA registration.
Further to the obvious disparity in laboratory testing methods, there is a large potential difference when it comes to durability, and thus cost effectiveness, of antimicrobial coated products versus copper and copper alloy products.
Antimicrobial copper ironmongery has a significant lifespan in the order of decades as it continuously kills microbes and never wears out, which is an essential requirement for busy healthcare environments where there is a high volume of human traffic.
The same cannot be said of coated products and questions remain to be answered. How durable are coatings? What happens if the active antimicrobial agent becomes scratched or depleted from the surface? Will the effective ‘dose’ from coatings be large enough and sustained over time?
Recent papers suggest there is a poor understanding of these issues.
Both antimicrobial copper and copper alloys that contain more than 60% copper have been globally recognised in laboratory and clinical trials for their antimicrobial qualities
These lingering doubts do not exist with established copper alloy ironmongery products such as Allgood’s Contego range.
Formed from an alloy containing antimicrobial copper, with the appearance of stainless steel, the Contego range uses a registered copper alloy in accordance with the Copper Development Association stewardship scheme and bears the Antimicrobial Copper brand’s Cu+ mark.
Hospitals and medical facilities strive to create the healthiest and most-hygienic environments possible. Consequently, in order to limit the spread of dangerous bacteria and disease, many facilities are now turning to antimicrobial copper to stop the spread of infections.
Therefore, to guarantee the long-term efficacy, durability and cost effectiveness of ironmongery designed to eradicate harmful pathogenic microbes in the medical sector, it is best to remember ‘if it’s not copper, it’s not proper’.