Disinfection of medical devices with a steam machine that operates at atmospheric pressure and is suitable for home usage.

Medical devices that come in direct contact with human skin or the oral cavity will inevitably be contaminated with microorganisms, including potential pathogens. Ensuring the microbiological safety of such devices is therefore crucial to prevent infections. Healthcare institutions usually have the facilities needed for effective sterilization of reusable medical devices. However, effective sterilization or disinfection of medical devices for usage at home has remained challenging both in terms of pathogen elimination and user safety. Preferably, this involves easy-to-operate equipment that works at relatively low temperatures and atmospheric pressure. In principle this need can be met by disinfection with steam. Therefore, the objective of the present study was to examine the efficacy of a simple electronic steam machine designed for home usage. Our results show that exposure to steam at 100 °C for 60 s resulted in complete eradication (100% reduction) of bacterial contaminants, including Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA). Significant bacterial reductions (ranging from ~ 90-100%) were also observed within shorter exposure times (10-30 s), depending on the strain. Importantly, the applied steam disinfection approach is effective even against biofilm-embedded bacteria, or bacteria applied to a medical device for home usage, as exemplified with a nebulizer that is used by patients with asthma or chronic obstructive pulmonary disease (COPD). In conclusion, our results provide quantitative proof-of-concept evidence that portable steam-generating devices that operate at atmospheric pressure can be used for effective disinfection of reusable medical devices in home settings.