We blogged last time on the first in a series of articles in the Journal of Infection Prevention about disinfection in healthcare. The first part in the series argues for routine disinfection of the healthcare environment. This second instalment describes the importance of standardised testing of disinfectants for hospitals.
The authors describe the bewildering choice of disinfectant chemistries and formulations that are now available for disinfecting healthcare surfaces. Infection Prevention and Control experts have a key role to play in ensuring that the most appropriate range of disinfectants are available to hospital cleaning teams. The key property of a disinfectant is its ability to kill microorganisms. Therefore, a crucial step in the process of selecting an appropriate disinfectant is ensuring that it has the required level and range of biocidal activity through standardised laboratory testing.
The article describes the family of European testing standards (EN standards) that are currently available, including both suspension testing methods, which test the ability of a disinfectant to kill microorganisms in a liquid suspension, and surface/carrier testing methods, which test the ability of a disinfectant to kill micro-organisms dried onto a surface. Key considerations when considering testing standard include:
On a more practical level, it is vital to perform disinfectant testing in accredited laboratories who are experienced at performing this sort of testing. Otherwise, common pitfalls can occur and efficacy can be over-estimated. Commonly, disinfectant neutralisation is not performed adequately, meaning that the actual contact time is longer than the intended contact time and the efficacy of the disinfectant is over-estimated. For example, many ‘sporicidal’ disinfectants that are on the market do not exhibit meaningful sporicial activity when tested using appropriate laboratory methods. Therefore, when reviewing a disinfectant for use in a hospital, it is wise to ask the following questions:
Biocidal activity is a vital factor in selecting an appropriate disinfectant. However, other factors are also crucial when selecting the right disinfectant, including the mode of application, environmental impact, potential occupational exposure issues, and formulation. These factors must be considered together when selecting the most appropriate hospital disinfectant.
A new review in the Journal of Infection Prevention by Dr Evonne Curran and colleagues sets out the arguments for and against the routine use of disinfectants in the healthcare environment. The review dispels some of the common arguments used against the routine use of disinfectants in the healthcare environment, and presents a novel risk-based scheme for deciding when to use detergent only for cleaning surface in the healthcare environment (which is not very often!).
Historically, the use of detergent cleaning only without the use of a chemical disinfectant has been the favoured model for cleaning the healthcare environment in the UK (whilst other countries have historically taken a more disinfectant-centric approach). However, we now know that detergent cleaning only does not reliably eliminate pathogenic micro-organisms from surfaces, and can inadvertently spread pathogens between surfaces. Therefore, routine use of disinfectants in the healthcare environment is becoming more common.
This review article examines the common arguments against the routine use of disinfectants in the healthcare environment:
The article also makes a case that the traditional approach to risk assessment for when to use a disinfectant and when to use a detergent needs to be re-evaluated in light of modern healthcare, restricting the use of detergent-only cleaning to settings outside of the patient zone when no medical equipment is around.
In summary, the use of disinfectants for cleaning and disinfecting the healthcare environment is evidence based, maximises patient safety, and is likely to be at least cost-neutral if not cost-saving.