This is the second in a series of four articles by Dr Andrew Kemp JP PhD RGN FBICSc L/RAMC, CEO at AK Medical Ltd, intended to shed some light on the many issues that are stopping the necessary changes required in the way we approach chemical disinfection and decontamination of surfaces.
I am grateful to Birkin Cleaning Services Ltd for its sponsorship of these articles. It is probably worth mentioning that this company is, in my view, at the absolute cutting edge of cleaning technologies and practices.
Myth and Legend? Or - we have always done it like this, but why, and what is the truth?
There can be no argument that there are certain routines and rituals that we use when cleaning every day, for which there is no hard evidence for, or against. Is it that we are happy to continue doing the same thing over, and are happy with the results, or is there something else to this? Perhaps common sense is no longer valued or is it simply too expensive to continue with protocols that have never been examined properly? A part of the problem we have in this area of research, is the lack of fast and accurate tests for bioburden on surfaces and on the skin (more about that next in next month’s article). A Basic truth was discussed in last month’s article, when we looked at attitudes towards cleaning and in particular disinfection. If risk is not seen, it is not dealt with, this is probably why the basic chemistry of every disinfectant available today is over 60 years old.
It may come as somewhat of a surprise to most of you that, there is very little routine testing of surface and skin contamination in healthcare institutions. There are two very good reasons for why this is the case:
1. Current “gold standard” tests (culture/ PCR) are expensive, can take up to 48 hours to get a result, and there is therefore no correlation to the surface and the results by the time you get them. This is too long to allow for meaningful corrective actions.
2. Current “gold standard” tests are at best considered inaccurate. It is estimated that standard culture techniques can get a result on surfaces it can be as little as 15% of the time. The results are therefore so far removed from the actual contamination levels, that it is impossible to determine corrective actions from them. PCR will count live and dead bacterial DNA, as such is almost useless as a surface cleaning test.
Both of these should be a good enough reason to develop a new test that will be used routinely to tell us how clean our healthcare facilities really are. Until we know that for certain, there will never be an accurate risk assessment as to the danger caused by those surfaces.
The results of global surveys on hospital cleaning and testing are frightening, with 80% or more of hospitals using visual inspection to determine bio burden on surfaces, and almost nothing done to routinely test the skin on hospital workers hands. The other 20% is made up of either the “gold standard” culture as described above, or total ATP counts. Total ATP is of absolutely no use, as even a zero count can be wrong and at best misleading (read my joint paper with Professor Mathew Diggle “How do we clean up this mess? – A review of testing methodologies”).
There is a saying in management circles - “If you can measure it, you can improve it”. This is also true for cleaning and disinfection practice. Another way of looking at this is - if you can’t test it, or don’t test it, it is impossible to know how effective you have been or if you have improved.
It is clear to those who look at this subject that, we need to produce better tests that accurately show contamination levels and species in real time, so that can these can be used to test the efficacy of chemical disinfectants (the tests methodologies our regulators use now are also worse than useless). In order to fully understand the true levels of bioburden and disinfectant resistant bacteria, amongst the many things we need to do, is to routinely test immediate efficacy as well as the efficacy of disinfectants over longer time periods. This will help us to see the true picture of the surface and skin bioburden levels in our hospitals. Only then will we be able to determine the true gravity of our situation. If we can measure it accurately, we will be able to improve it.
There are testing technologies in many University laboratories that can test bioburden accurately, and in fact the recent introduction to civil use of a military test for biological weapons, shows us that it is possible to develop tests that are accurate and fast enough to be of use, however, none of these technologies are readily available in our healthcare facilities yet.
We used the biological weapons test to look at the use of microfibre mops and cloths and presented the results at a British Institute of Cleaning Science awards meeting.
Standard mop head – changed 2 x per day, industrial wash 80 C (water and Sodium hypochlorite 5000 ppm?)
CFU count per cm2 start of the day: 17
CFU count after 1 hour: 217
CFU count after 2 hours: 212
CFU count when changed: 208
Microfibre mop head – changed 2 x per day, single use (water and detergent only)
CFU count per cm2 start of the day: 11
CFU count 1 hour: 1411
CFU count 2 hours: 3687
CFU count prior to bin: 2875
These results contradict some manufacturers claims that no detergents or disinfectants are necessary when using this type of material in cloths and mop heads. Similar results were found by Professor Maillard at Cardiff University. It is clear then, that detergents and disinfectants are still required to significantly reduce bioburden even when using microfibre mops and cloths.
This type of surface and skin test is very accurate and fast, however, although it shows a total live bacteria count, it does not show the bacterial species. More work needs to be done on this type of technology to improve the tests, so that they show not just total counts, but can identify species from the same sample and in the same time frame. In my first paper looking at the use of alcohol gels for hand sanitation, I showed that after 1 hour an alcohol gel increases bacterial counts on skin by 2 1⁄2 times more than soap and water alone (see my paper “Alcohol gels – more harm than good?). Unfortunately, I didn’t think to look at the species type, simply the numbers, as I had assumed that the species would remain the same. It took a TV show “The Twinstitute”, to show us all that in factthere was a species change from Staphylococcus Epidermidis, a normal skin commensal, which is not thought to be particularly pathogenic (harmful), to a highly pathogenic Bacillus that has been known to grow in alcohol, and that has killed an unknown number of patients.
Once new, reliable and rapid tests are available, perhaps the results will stimulate the chemical industry to produce new disinfectants that meet the needs of healthcare. For the moment, we must stop accepting poor results from our disinfectants, and start insisting on excellent results. If we do not do this now, we may end up losing both the “cure” and the “prevention” battles to the microbes. The microbes we are trying to kill, are adapting and becoming resistant all the time, they are therefore clearly far smarter than some of the people responsible for infection prevention around the world.
In my next article I will look at the industrial marketing of cleaning chemistries and at how our regulatory bodies are letting us down.
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