Legionnaires’ disease continues to present a significant risk in the UK, as latest figures form Public Health England illustrate. Risks are all the more acute in the healthcare setting, where many patients who may be highly susceptible to infection receive care. The problem is exacerbated by the often large and complex nature of water systems in healthcare premises and the potential for changes in use of parts of the system, which can increase risks.
To control risks from Legionnaires’ disease, a range of measures need to be applied and managed effectively. Guidance on how this can be achieved is published by the Health and Safety Executive (HSE) and, for healthcare in particular, the Department of Health (DH). Fundamental to effective control is risk assessment, which identifies those measures that need to be applied and how efficacy is monitored. Keeping water systems clean, maintaining suitable temperature profiles and biocide dosing levels and ensuring good water turnover is essential. Monitoring these control measures can provide assurances that control is being maintained, but both HSE and DH advise that testing for the presence of the bacteria in some healthcare situations is also necessary.
Traditional testing methods for legionellae in water systems involves culturing the bacteria in a laboratory. Depending on the level of testing undertaken, this can represent a significant burden on healthcare budgets, but perhaps the main issue with traditional methods is the time that it takes to receive confirmed test results. Delays of up to two weeks are typical and this can lead to missed opportunities to apply additional measures to control risks identified by the testing.
Significant efforts have been expended to address this matter and this paper examines new developments in the field of rapid testing for legionellae, exploring the advantages and disadvantages of some of the new approaches.