Efficacy of Hydrogen Peroxide Vaporizing Against Methicillin-Resistant Staphylococcus aureus, Extended-Spectrum β-Lactamase-Producing Bacteria, and Clostridioides difficile.

Background: Environmental contamination with drug-resistant bacteria and spore-forming organisms such as Clostridioides difficile poses a significant risk of healthcare-associated infections (HAIs). While manual disinfection using disinfectant-impregnated cloths is standard practice, it is susceptible to human error and may leave residual contamination by pathogens.

Methods: We evaluated the bactericidal efficacy of hydrogen peroxide vaporizing using a compact device (NOCOSPRAY2) in a simulated hospital room (28.8 m³). Surfaces were inoculated with methicillin-resistant Staphylococcus aureus (MRSA, ATCC43300), ESBL-producing Escherichia coli (NCTC13353), or C. difficile (ATCC9689), followed by drying. Vaporizing was performed at three different settings: 2-minute spray + 60-minute contact (1×), 6-minute spray + 90-minute contact (3×), and 9-minute spray + 90-minute contact (5×). Viable bacterial counts were determined post-vaporizing to calculate log reduction values.

Results: For MRSA, a significant bactericidal effect of ≥5 logs was observed after 6 minutes of vaporization. For ESBL-producing E. coli, a significant bactericidal effect of ≥5 logs was observed after 2 minutes of vaporization. For C. difficile, a significant sporicidal effect of ≥3 logs was observed after 2 minutes of vaporization. Hydrogen peroxide concentrations outside the room remained below safety thresholds throughout all tests.

Conclusion: Hydrogen peroxide vaporizing demonstrated broad-spectrum efficacy against drug-resistant and spore-forming organisms, including C. difficile, including high-touch surfaces commonly found in hospital settings. This no-touch disinfection method may serve as a valuable adjunct or alternative to manual cleaning for environmental decontamination in healthcare settings.