C. Djayet , A. Iwanoff , M. Boubaya , P. Moenne-Locoz , E. Carbonnelle , D. Seytre , M. Laleem , A. Izri , J.R. Zahar , A. Jacolot
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引用次数: 0
Abstract
Background
In hospitals, the prevention of healthcare-associated infections requires biocleaning of the patient's immediate environment. Micro-organisms can survive for long periods of time – up to several months – on certain environmental surfaces, resulting in their transmission to the patient through direct contact or via the hands of healthcare workers. Dry heat is a long-recognized antimicrobial process. However, its use as an aerial method of disinfection for hospital surfaces is innovative. An evaluation of bactericidal efficacy is required before any real-world application, to ensure that this method satisfies current standards.
Aim
In this study, we aimed to investigate the effect of dry heat generated at a temperature of 60 °C for 30 min on the bacterial contamination of horizontal surfaces in a room, comparing this method with disinfection by the direct application of a detergent-disinfectant – the current reference method.
Methods
Four supports, made from the materials most commonly found in patient rooms, were inoculated with five different bacterial species representative of hospital ecology and tested. More than 900 bacteriological samples were taken at different times after the disinfection phase.
Findings
The bactericidal activity of the dry heat process was demonstrated by a decrease in bacterial levels of more than 5 log10 cfu/mL in 10 min, regardless of bacterial species or substrate. After 30 min, dry heat was significantly more effective than detergent-disinfectant and mechanical action alone.
Conclusion
Dry heat (60 °C for 30 min) showed bactericidal activity against non-spore-forming vegetative bacteria under the conditions tested in this study. This method can be automated, meets ecological criteria and is not toxic to humans; it may represent a potential alternative for surface disinfection using quaternary ammonium disinfectants against vegetative bacteria, although further investigation is required to confirm efficacy against other clinically relevant pathogens.
期刊介绍:
The Journal of Hospital Infection is the editorially independent scientific publication of the Healthcare Infection Society. The aim of the Journal is to publish high quality research and information relating to infection prevention and control that is relevant to an international audience.
The Journal welcomes submissions that relate to all aspects of infection prevention and control in healthcare settings. This includes submissions that:
provide new insight into the epidemiology, surveillance, or prevention and control of healthcare-associated infections and antimicrobial resistance in healthcare settings;
provide new insight into cleaning, disinfection and decontamination;
provide new insight into the design of healthcare premises;
describe novel aspects of outbreaks of infection;
throw light on techniques for effective antimicrobial stewardship;
describe novel techniques (laboratory-based or point of care) for the detection of infection or antimicrobial resistance in the healthcare setting, particularly if these can be used to facilitate infection prevention and control;
improve understanding of the motivations of safe healthcare behaviour, or describe techniques for achieving behavioural and cultural change;
improve understanding of the use of IT systems in infection surveillance and prevention and control.