In vitro-in vivo sequence studies as a method of selecting the most efficacious alcohol-based solution for hygienic hand disinfection

Clin Microbiol Infect. 2010 May;16(5):518-23. doi: 10.1111/j.1198-743X.2009.02827.x.

Abstract

The use of alcohol-based hand rubs serves to reduce hospital-acquired infections. Many products of this type are now on offer and it is essential to know how to rank their efficacy. A sequence of tests is proposed here to compare any given new alcohol-based solution against the reference solution (60% 2-isopropyl-alcohol) with 30 s of contact time: (i) in vitro (with pig skin as carrier) testing of >30 species of microorganism; (ii) in vitro assessment of residual efficacy (after 30 min of drying); (iii) in vivo study of transient microbiota (modification of the EN 1500 standard procedure) using four ATCC strains; (iv) in vivo study of resident hand microbiota. After performing the in vitro evaluation of seven alcohol-based hand rubs, the two most efficacious (chlorhexidine-quac-alcohol and mecetronium- alcohol) were chosen and studied, comparatively with the reference solution (60% isopropyl alcohol), in vitro (for chemical sustainability on the skin) and in vivo (against transient and resident microbiota). Chlorhexidine-quac-alcohol proved to be significantly superior to mecetronium-alcohol or the reference solution in all tests, except against resident microbiota for which the improvement was not statistically significant.

MeSH terms

  • 2-Propanol / administration & dosage*
  • Alcohols
  • Analysis of Variance
  • Animals
  • Anti-Infective Agents, Local / administration & dosage*
  • Bacteria / drug effects*
  • Chlorhexidine / administration & dosage
  • Hand Disinfection / methods*
  • Humans
  • Quaternary Ammonium Compounds / administration & dosage
  • Skin / microbiology
  • Solutions
  • Swine

Substances

  • Alcohols
  • Anti-Infective Agents, Local
  • Quaternary Ammonium Compounds
  • Solutions
  • ethylhexadecyldimethylammonium
  • 2-Propanol
  • Chlorhexidine