Elizabeth De Nardo 1, Christine Claighen 1, Christopher Beausoleil 1, Terri Eastman 1
1 Gojo Australasia, Macquarie Park, NSW, Australia
Background: Multidrug-Resistant Organisms (MRO) are often passed from person to person by the hands of caregivers. Cleaning hands with soap and water or use alcohol-based hand rubs (ABHR) are the main recommendation by The World Health Organization (WHO)for preventing the spread of MRO. However, the efficacy of hand hygiene products against MRO is not well documented.
Experimental Methods: Two commercial ABHR (gel and foam) and one antimicrobial foaming hand wash with 0.3% triclosan (TCS) available in Australia were evaluated using a 15 second in vitro Time-Kill (ASTM E 2315) against up to 15 different strain of antibiotic susceptible and resistant bacteria. Additionally, ABHR with 62% ethanol, antimicrobial hand wash with 4% chlorhexidine gluconate (CHG), and antimicrobial foaming hand wash with 0.3% triclosan were evaluated by an in vivo hand wash method (ASTM E 2755-10) against MRSA (strain ATCC #33591).
Results: By in vitro testing, ABHR gel or foam 70% reduced all bacteria strains tested by ≥6 log10 (≥ 99.9999%) in 15 seconds. By in vivo testing, the 62% ethanol ABHR and TCS hand wash produced LRs of 2.05 and 1.93, respectively and were statistically equivalent. The CHG hand wash produced a 1.53 LR and was statistically inferior to the alcohol sanitizer and TCS hand wash.
Conclusions: No differences in susceptibility to ABHR 70% alcohol was shown by antibiotic resistant bacteria when compared to the sensitive strains. Hand washes should be chosen carefully due to the variable susceptibility showed by MRSA strains tested, and the formulation specific performance of these biocides.