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A Method to Test the Efficacy of Handwashing for the Removal of Emerging Infectious Pathogens
Published on: June 7, 2017
Lasting hand self-disinfection: A backup for hospital hand hygiene?
Rafael Herruzo1, Rubén Yela1, Maria Jose Vizcaino1
1Department of Preventive Medicine, Public Health, and Microbiology, Faculty of Medicine, Autonomous University of Madrid, Madrid, Spain.
Background:
Hand disinfection should be performed on the occasion of 5 separate moments during patient care, but some occasions are skipped. Can using hand antiseptics with residual effect reduce the problem of infection spread? We evaluated a 30-minute residual effect by different antiseptic products on endogenous and acquired microbiota.
Methods:
The products tested were 2% and 5% chlorhexidine, 1% and 10% iodine povidone, 60° n-propanol, 0.2% mecetronium + isopropanol, and 0.6% chlorhexidine + isopropanol + 0.1% benzalconium chloride. The microorganisms identified were 3 ATCC and 9 multiresistant strains isolated from intensive care unit patients (used as acquired microbiota). Logarithmic (log10) reductions of the colony forming units obtained with each antiseptic product and for each microorganism were calculated via in vivo (6 volunteers) and in vitro tests.
Results:
The better in vivo and in vitro products with a residual effect > 2 log10 after 30 minutes on hands were 2%-5% chlorhexidine and 0.6% chlorhexidine + isopropanol + 0.1% benzalconium chloride. This reduction was significantly different (P < .01) from the other 4 antiseptics. This residual effect (> 2 log10) can be considered a self-disinfecting hand status in daily practice.
Conclusions:
Hand antiseptics used in hospitals must pass tests of residual efficacy (after 30 minutes on acquired microbiota) showing a reduction > 2 log10 in vivo and in vitro. A good product can be the mixture of chlorhexidine + alcohol + benzalconium chloride.
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