We need an appropriate antimicrobial test standard for indoor touch surfaces

Concerned by HCAIs (infections acquired during healthcare) and Antimicrobial Resistance?

Here’s something you should know…

Use of effective antimicrobial surfaces, as a simple supplement to good hand hygiene and cleaning regimes, has been proven to reduce not only microbial bioburden on frequently-touched surfaces but also patient infection rates.

In healthcare, fewer infections mean better healthcare efficiency (clinical cost-savings and freed-up beds) and improved patient outcomes.

Thus far, no major surprises… but what about this?
Not all antimicrobials are equal and there is no universally-adopted standard test protocol to measure their effectiveness ‘in the field.’

How, then, can we identify and specify appropriate antimicrobial surfaces to use in construction or refurbishment projects?

Healthcare scientists and clinicians urge careful stewardship of antimicrobial agents; this includes antimicrobial surfaces as well as antibiotic drugs.

Some commonly-used antimicrobial surfaces – which work under the standard “warm and wet” test protocols* – have negligible efficacy under typical indoor conditions.**

Using such surfaces could actually aggravate the problem of antimicrobial resistance, which the WHO described in April 2015 as “the single greatest challenge in infectious disease today.”

There are appropriate tests currently available in the UK which are ready to be used.***

Until we agree an appropriate test standard for antimicrobial efficacy – relevant to touch surfaces under typical indoor conditions – needless suffering will continue and we will deny ourselves a simple yet effective measure that improves healthcare and helps combat antimicrobial resistance.

Regulators such as the US EPA and the OECD are aware of this. The OECD Working Group under the Inter-Organisation Programme for the Sound Management of Chemicals (IOMC), which represents the interests of a number of countries and regions, has proposed a tiered system approach with Tier One test methods providing proof of principle and Tier Two methods more closely representing in-use environmental conditions.

For a more comprehensive explanation, with details of efficacy tests performed on Antimicrobial Copper,  visit: http://www.antimicrobialcopper.org/uk/efficacy-tests-and-standards

 

So, the next time a salesman or colleague talks to you about an antimicrobial surface, ask:-
a) is it able to make public health benefit claims?
b) does it work rapidly, under typical indoor conditions?
c) how does it work – does it actually destroy microbes?
d) how durable is the antimicrobial protection?
e) is use of this product likely to contribute to AMR?
f) for evidence – not claims, but test protocols and results over time
and, last but not least:

g) help raise awareness of the need for an appropriate test standard for antimicrobial efficacy under typical indoor conditions!

 

We welcome your suggestions: please contact us.

 

 

* JIS Z 2801 or ISO 22196 (measure microbial reduction at 24 hours exposure, under elevated temperature and saturated humidity conditions).

** Michels, H.T., Noyce, J.O. and Keevil, C.W. (2009), Effects of temperature and humidity on the efficacy of methicillin-resistant Staphylococcus aureus challenged antimicrobial materials containing silver and copper. Letters in Applied Microbiology, 49: 191–195. doi: 10.1111/j.1472-765X.2009.02637.x
http://onlinelibrary.wiley.com/doi/10.1111/j.1472-765X.2009.02637.x/full

*** OECD is aware of the limitations of standard tests, which OECD class as Tier 1 tests.
The available tests referred to in this post constitute Tier 2 tests as per para 2 on page 8 of OECD  “GUIDANCE DOCUMENT FOR QUANTITATIVE METHOD FOR EVALUATING ANTIBACTERIAL ACTIVITY OF POROUS AND NON-POROUS ANTIBACTERIAL TREATED MATERIALS”  ENV/JM/MONO(2014)18 dated 11th July 2014
“2. The method provides only a basic foundation for conducting tests on antimicrobial treated articles, and a second tier method must be developed to ensure an accurate assessment of antimicrobial activity. A guidance document is currently under development for tier 2 testing, i.e. laboratory-based tests to substantiate claims made for the article with test conditions that simulate intended use, durability and compatibility of the article – provided that the protocol describes the claim being supported in an adequate manner. Further, Tier 2 testing protocols will also accommodate use of shorter contact times (e.g. 2h) and inoculum dried on treated surfaces.”
See http://www.oecd.org/officialdocuments/publicdisplaydocumentpdf/?cote=ENV/JM/MONO(2014)18&doclanguage=en