I was doing a talk on canine and feline infectious diseases in shelter environment yesterday evening, and as usual, I like to ask questions to the audience (good way to see if they can stand my Franglish right?). This is one of my favourite: do you know what is the difference between cleaning and disinfecting? Interesting to see the look in the eyes of people at this very moment: you can see them wondering why I am asking what they usually consider as “such a basic question”. Never got anything else than a big YES as an answer… But then I followed up and asked my second question (because it’s all part of a plan, right?): what are you using as a cleaner ?
First answer: bleach. Perfect counter-example, my demonstration was made!!! Bleach is indeed an excellent disinfectant, but when it comes to pure cleaning, its something you should definitely avoid doing…
Getting lost? Ok, let’s start again from the beginning!
Cleaning: making something free of dirt, which means removing the organic matter (feces for instance). When you clean, your target is physical cleanliness.
Disinfecting: destroy or prevent the growth of disease-carrying microorganisms. You’re now targeting the germs remaining in the environment; your goal is to obtain bacteriological cleanliness.
Why is it so important? Because you cannot clean AND disinfect at the same time, this always needs to be a two-step process! Bleach for instance is a very good disinfectant, but if you use it to clean, it will be inactivated in the presence of organic matter. So again if you are using bleach as a cleaner, which is an improper use of the product, plenty of germs are still in the environment when you think you’re done. You feel like you’re protected, while in fact, this is absolutely not the case… Look at the following figure, here are the different mandatory steps of the process!
And what about those products that claim to “clean and disinfect”? Well, some of them indeed do have some detergent activity (this is the case for quaternary ammoniums or accelerated hydrogen peroxide) but again, if you read carefully the labels, it is clearly written: this two-step procedure is always needed (even if you use the same product, first you clean, then you rinse, then you disinfect).
So it’s important to make this clear with your staff: they must not cut corners in the cleaning and disinfecting protocol. It is important to clearly follow the rules to make the process fully efficient: respecting the adequate concentrations (for instance bleach will destroy parvovirus when diluted at 1:32 while to inactivate ringworm, you’ll need to do it a 1:10!) and the contact length (most of the disinfectant will need to remain 10 minutes on the surfaces to be fully efficient, new disinfectants need 1-5 minutes and no further rinsing is needed, but there are more expensive then!).