Reduction in MRSA environmental contamination with a portable HEPA-filtration unit

Area of Science:

• Infection Control and Hospital Epidemiology
• Environmental Microbiology
• Public Health

Background:

• The hospital environment is a significant factor in the transmission of nosocomial pathogens like methicillin-resistant Staphylococcus aureus (MRSA).
• Effective strategies are needed to reduce environmental contamination and prevent cross-infection in clinical settings.

Purpose of the Study:

• To evaluate the efficacy of a portable high-efficiency particulate air (HEPA) filtration unit in reducing MRSA surface contamination.
• To assess the impact of different air filtration rates on MRSA reduction in patient isolation rooms.

Main Methods:

• Agar settle plates were used to measure MRSA contamination rates on horizontal surfaces in rooms of MRSA-dispersing patients.
• Contamination levels were compared between periods with and without HEPA filtration.
• Poisson regression analysis was employed to compare contamination rates at varying filtration levels (60-235 m³/h).

Main Results:

• Without filtration, 80-100% of settle plates were positive for MRSA, with mean colony-forming units (cfu) ranging from 4.1 to 27.7 per plate.
• HEPA filtration at 140 m³/h and 235 m³/h significantly decreased MRSA contamination rates (adjusted rate ratios 0.037, 0.099, 0.248; P < 0.001).
• A strong association was observed between higher air filtration rates and reduced MRSA cfu counts (P for trend < 0.001).

Conclusions:

• Portable HEPA filtration units are effective in significantly reducing MRSA environmental contamination in patient isolation rooms.
• This technology can be a valuable adjunct to current MRSA infection control measures.
• Implementing HEPA filtration may help mitigate the spread of MRSA within healthcare facilities.