181327 In-vitro susceptibility of hospital-acquired, community-acquired, and laboratory MRSA strains to topical antiseptics

Monday, October 27, 2008: 8:35 AM

Cara A. M. Bondi, MPH , Research & Development, GOJO Industries, Incorporated, Akron, OH
Carrie A. Zapka, MS , Research & Development, GOJO Industries, Incorporated, Akron, OH
Sarah L. Edmonds, MS , Research & Development, GOJO Industries, Incorporated, Akron, OH
Danyelle Wieland, BS , In-Vitro Laboratories, Bioscience Laboratories, Incorporated, Bozeman, MT
David R. Macinga, PhD , Research & Development, GOJO Industries, Incorporated, Akron, OH
James W. Arbogast, PhD , Research & Development, GOJO Industries, Incorporated, Akron, OH
Background: Methicillin-resistant Staphylococcus aureus (MRSA) strains are increasingly problematic hospital-acquired (HA) and community-acquired (CA) pathogens. Hand hygiene is widely recognized as a key component of prevention and control for MRSA, although the efficacy of topical antiseptics has primarily been established based on performance against laboratory MRSA strains. However, the correlation between laboratory and pathogenic clinical strains has not been determined.

Methods: A time-kill procedure with a 15 second exposure was used to assess the susceptibility of Staphylococcus aureus strains to topical antiseptics. A laboratory methicillin-suseptible S. aureus (ATCC 6538), a laboratory MRSA (ATCC 33591), clinical HA-MRSA (USA200, USA 500), and clinical CA-MRSA (USA300, USA400, USA1000, USA1100) were used to challenge 14 antiseptics with different active ingredients (ethanol, triclosan, chloroxylenol, or chlorhexidine gluconate).

Results:

• Products with >62% ethanol achieved a >6 log reduction against all strains

• Products with non-ethanol actives generally had inferior efficacy to ethanol with log reductions ranging from <1 log to >5 log

• Strain susceptibility to topical non-ethanol antiseptics is variable; USA1100 was the most resistant

• Laboratory S. aureus MRSA has intermediate resistance against topical antiseptics and appears to be predictive of clinical strain susceptibility

Conclusions:

• As demonstrated by the results of this study, CDC recommendations for alcohol-based instant hand sanitizer use to control and prevent MRSA are supported

• Hand hygiene products containing non-alcohol active ingredients have variable efficacy

• Efficacy data for non-alcohol hand hygiene products should be evaluated prior to use in areas at risk for HA-MRSA and CA-MRSA transmission

Learning Objectives:
1. Summarize the CDC hand hygiene recommendations for the prevention and control of MRSA. 2. List the four most common antibacterial ingredients used in topical antiseptics. 3. Articulate the reasons that alcohol based instant hand sanitizers are the best hand hygiene option for the control and prevention of MRSA.

Keywords: Disease Prevention, Communicable Disease

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: Work for GOJO Industries
Any relevant financial relationships? Yes

Name of Organization Clinical/Research Area Type of relationship
GOJO Industries, Inc. Infection Control Employment (includes retainer)

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.