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MoWa: A Disinfectant for Hospital Surfaces Contaminated With Methicillin-Resistant Staphylococcus aureus (MRSA) and
Tyler V Gregory1,2, Karen Ellis3, Renzo Valeriani3
1Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, MS, United States.
Introduction:
Staphylococcus aureus strains, including methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA), are a main cause of nosocomial infection in the world. The majority of nosocomial S. aureus-infection are traced back to a source of contaminated surfaces including surgery tables. We assessed the efficacy of a mixture of levulinic acid (LA) and sodium dodecyl sulfate (SDS), hereafter called MoWa, to eradicate nosocomial pathogens from contaminated surfaces.
Methods And Results:
A dose response study demonstrated that MoWa killed 24 h planktonic cultures of S. aureus strains starting at a concentration of (LA) 8.2/(SDS) 0.3 mM while 24 h preformed biofilms were eradicated with 32/1.3 mM. A time course study further showed that attached MRSA bacteria were eradicated within 4 h of incubation with 65/2 mM MoWa. Staphylococci were killed as confirmed by bacterial counts, and fluorescence micrographs that were stained with the live/dead bacterial assay. We then simulated contamination of hospital surfaces by inoculating bacteria on a surface prone to contamination. Once dried, contaminated surfaces were sprayed with MoWa or mock-treated, and treated contaminated surfaces were swabbed and bacteria counted. While bacteria in the mock-treated samples grew at a density of ~104 cfu/cm2, those treated for ~1 min with MoWa (1.0/0.04 M) had been eradicated below limit of detection. A similar eradication efficacy was obtained when surfaces were contaminated with other nosocomial pathogens, such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, or Staphylococcus epidermidis.
Conclusions:
MoWa kills planktonic and biofilms made by MRSA and MSSA strains and showed great efficacy to disinfect MRSA-, and MSSA-contaminated, surfaces and surfaces contaminated with other important nosocomial pathogens.
Insights
A novel disinfectant mixture of levulinic acid (LA) and sodium dodecyl sulfate (SDS), called MoWa, effectively eradicates Staphylococcus aureus, including MRSA, from contaminated surfaces. This study demonstrates MoWa
Area of Science:
- Microbiology
- Infectious Diseases
- Surface Chemistry
Background:
- Nosocomial infections caused by Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), pose a significant global health threat.
- Contaminated surfaces, such as surgical tables, are a primary source for the transmission of S. aureus in healthcare settings.
- Effective surface disinfection strategies are crucial for preventing the spread of hospital-acquired infections.
Purpose of the Study:
- To evaluate the efficacy of a levulinic acid (LA) and sodium dodecyl sulfate (SDS) mixture (MoWa) in eradicating nosocomial pathogens from contaminated surfaces.
- To assess MoWa's effectiveness against both planktonic and biofilm forms of S. aureus, including MRSA and MSSA strains.
- To determine MoWa's efficacy in disinfecting surfaces contaminated with various common nosocomial pathogens.
Main Methods:
- Dose-response and time-course studies were conducted to determine the optimal concentrations and contact times for MoWa against S. aureus.
- Bacterial eradication was confirmed using bacterial counts and live/dead staining with fluorescence microscopy.
- Simulated hospital surfaces were contaminated with S. aureus and other pathogens, treated with MoWa, and then swabbed for bacterial enumeration.
Main Results:
- MoWa effectively killed planktonic S. aureus at concentrations as low as 8.2/0.3 mM (LA/SDS) and eradicated 24-hour preformed biofilms at 32/1.3 mM.
- Attached MRSA bacteria were eradicated within 4 hours using 65/2 mM MoWa.
- A 1-minute application of MoWa (1.0/0.04 M) eradicated S. aureus from contaminated surfaces to below the limit of detection, a significant improvement over mock-treated samples (~10^4 cfu/cm^2).
- Similar eradication efficacy was observed for other nosocomial pathogens, including Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus epidermidis.
Conclusions:
- The MoWa mixture demonstrates potent antimicrobial activity against planktonic and biofilm forms of S. aureus (MRSA and MSSA).
- MoWa is highly effective in disinfecting surfaces contaminated with S. aureus and other significant nosocomial pathogens.
- This LA/SDS mixture presents a promising solution for surface disinfection in healthcare environments to combat nosocomial infections.
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