A helpful overview about disinfection, what it really means, and some considerations for pest managers thinking about branching out into offering professional cleaning services.
With the COVID-19 pandemic in full swing and a recession looming, pest managers are looking at alternative revenue streams and disinfection services are an obvious opportunity. Indeed many of the global pest control companies already provide hygiene services. So what are the basics?
Firstly it is important to understand the difference between cleaning, sanitisation, disinfection and sterilisation. Using the definitions provided by the Centre of Disease Control and Prevention in the US:
- Cleaning is the removal of visible dirt (organic and inorganic materials) from objects and surfaces. This needs to occur before any disinfection or sterilisation treatment
- Sanitisation is often used interchangeably with ‘cleaning’ but actually takes cleaning to the next level and provides some degree of disinfection
- Disinfection describes a process that eliminates many or all pathogenic organisms, except bacterial spores
- Sterilisation is a process by which all forms of microbial life are destroyed as would be required for equipment used in medical procedures.
Any pest manager looking to offer professional hygiene services will most likely be offering cleaning/sanitisation, and possibly disinfection services too (but not sterilisation).
The aim of disinfection is to eliminate microbes that can contaminate food and cause illness. Microbes by definition cannot generally be seen with the naked eye, although well-developed fungal colonies will be visible.
As such, when disinfecting premises, generally the treatment is targeting bacteria, fungi and viruses. These are very different organisms. From a classification point of view, fungi and bacteria are classed into their own kingdoms. Viruses however are not classified in the same way as they are not actually independent living organisms. They are parasites that cannot reproduce by themselves. They need to invade the cells of living organisms to hijack the cell machinery for replication.
Whilst a number of products will have various fungicidal, bactericidal and virucidal properties, as with pest control products you need to look at the label to confirm which microbes are targeted by the product in question. In addition, especially for high-level disinfection, it is important to know whether the disinfectant kills the bacterial and fungal spores as well as the bacteria and fungi themselves.
Disinfection is primarily about treating surfaces. In order to disinfect a surface for a particular microbe, it is necessary to choose a product that is active against the particular microbe, and one that is suitable for use on the surface in question. The product is then applied and left on the surface for the required amount of time to eliminate the microbes. It is important to mention that disinfectants do not have any residual properties, which is why surfaces in critical areas need to be disinfected on a regular basis.
As with insecticides, there are a range of active ingredients for disinfection, each with different modes of action and spectrums of control. Alcohol- based disinfectants are good general disinfectants and are known to be active against the influenza virus. However, in order to achieve a good level of control, the alcohol content has to be above 60%. Their assumed mode of action is one of protein denaturation. However, alcohols are not recommended for high-level disinfection and sterilisation as they lack sporicidal action and cannot penetrate protein-rich materials.
Two groups of disinfectants worth mentioning are the hypochlorites and quaternary ammonium compounds. Hypochlorites are the basis for household bleach formulations and provide strong, effective disinfection against a wide range of microbes, including viruses. They are a low-cost option and are widely used for surface disinfection in healthcare facilities. However, they are readily inactivated by organic material (so surfaces need to be clean) and users need to be careful during application not only from a personal safety point of view but also considering potential damage to surfaces due to corrosion or discolouration.
Quaternary ammonium compounds are widely used in a number of household and commercial disinfectants. However, they are generally only used for disinfection of non-critical surfaces as they are not sporicidal. Independent testing on bacteria has shown variable results and they do not work on hydrophilic (non-enveloped) viruses. However, they are active against lipophilic (enveloped) viruses such as corona viruses.
Currently the Australian Department of Health is specifying the use of freshly diluted bleach solution with a contact time of at least ten minutes as the main option for disinfection with regards to COVID-19. However, other products may be suitable depending on the circumstances, use situation and claimed virucidal performance. For example, a number of well-known household disinfectants containing quaternary ammonium compounds have therapeutic-approved claims specifying performance on corona viruses.
However, suppliers of products and services that make claims regarding disinfection need to comply with the Therapeutic Goods Act 1989. In particular any product or service making specific claims other than “disinfection” will need to comply with the act. For products it means they need supporting data and the product needs to be included in the Australian Register of Therapeutic Goods. For pest managers, this means any claims they make should match the claims made on the products being used and should not be embellished.
For example, the previously mentioned household products making corona virus claims would not have been tested on SARS- CoV-2, but were likely tested on other corona viruses such as the original SARS virus and MERS. This allows them to make a general corona virus claim; it does not allow them to make the specific claim that it kills SARS-CoV-2. It is doubtful any product can yet make this claim as the virus is so new and no testing will have been carried out. Consequently, no one offering professional disinfection services can claim to make a premises ‘free of COVID-19’.
In addition to suitable training, it is also worth noting that offering disinfection services requires appropriate insurance and it is unlikely to be part of the pest- control-specific policies. So speak to your insurance provider if you are intending to branch out into cleaning and disinfection services to ensure you are fully covered.