Hand Hygiene: Antimicrobial Activity Comparison of Three Alcoholic Products – Gel and Liquid – in the Hands with Organic Material

BACKGROUND/OBJECTIVES: Alcohol is the preferred agent for hand hygiene (HH) and is indicated to be used when hands are not visibly dirty with proteinaceous material but an inadvertent handʹs contact with blood and organic matter can occur during routine patient care. OBJECTIVE: to compare the antimicrobial activity of three alcoholic products, commonly used in Brazil, in the hands with organic material (OM). METHODS: Fourteen healthy volunteers were randomized in 3 groups, using modified European Standard EN 1500 and cross-over design. The test-products (TP) were ethanol: A – gel 62%, B – gel 70% and C – liquid 70% with glycerol 2% and the reference-product (RP): D – alcohol isopropanolol 60% and they were used on artificially contaminated hands with S.marcescens ATCC 14756 and sheep blood as OM to simulate contamination. For each TP and RP the following sequence was carried through: hands were washed with soft soap, 1,2 ml of sterile sheep blood defibrinated was dispensed by sterile syringe into the hands, air-dried and immersed in the contamination fluid up to the mid-metacarpals. Bacterial samples were recovered for the inicial count by rubbing the fingertips of each hand for 1 min in the Petri dish containing tryptone soya broth (TSB). The hands were rubbed thoroughly over their entire surface (30 to 60 seconds) with 2–3 ml of the test products. The reference product was used twice (total of 6 ml) and rubbed for 60 seconds. Both hands were rinsed in running water and excess water was drained off. Final bacterial count was obtained rubbing the fingertips of each hand for 1 min in the Petri dish containing TSB. For both reference and test products, the mean log10 reduction factors (RF) were calculated (difference between the pre-value and post-value) and for testing the RF of the test products against that of reference product the Wilcoxon teste was used (level of significance was set at P = 0,1, one sided). RESULTS: The mean log10 RF for products A, B and C were: 3.29; 3.36 and 3.56 respectively and for D: 3.66. Wilcoxon test indicated: product A did not meet standard criteria (P = 0,074) and the products B (P = 0,198) and C (P = 0,826) met EN 1500 requirement. CONCLUSIONS: All the TP used in hands with OM, significantly reduced transient flora, more than 3 log10 (99,9% reduction). These results emphasize the advantage of alcohol use in the hand hygiene.