In-vitro and in-use efficacy of a rapid, targeted UVC decontamination system

Area of Science:

• Microbiology
• Infection Control
• Environmental Hygiene

Background:

• Ultraviolet C (UVC) decontamination systems supplement manual cleaning in healthcare settings.
• Current systems often use fixed, vertical bulbs for whole-room decontamination.

Purpose of the Study:

• Evaluate the in-vitro and in-use efficacy of a novel UVC device with articulating arms.
• Assess its capability for rapid, targeted decontamination in hospital rooms.

Main Methods:

• Inoculated stainless steel biological indicators with meticillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae, and Clostridioides difficile spores under varying soiling conditions.
• Measured bacterial recovery post-UVC decontamination.
• Assessed in-use efficacy by sampling aerobic colony counts (ACC) and C. difficile on surfaces before and after manual cleaning and UVC decontamination.

Main Results:

• Demonstrated significant log reductions for MRSA and K. pneumoniae across different soiling levels.
• Limited efficacy against C. difficile spores, particularly with high soiling.
• Manual cleaning left bacteria on 50% of surfaces; UVC decontamination reduced this to 30%, with C. difficile persisting on one surface.

Conclusions:

• The novel UVC system is effective for targeted disinfection of high-touch surfaces and equipment.
• Short cycle times enable use in time-sensitive areas like operating theatres.