Efficacy of Alcohol-based Hand Rinses Under Frequent-use Conditions

Fifty volunteers randomly assigned to one of five hand washing agents (10 subjects per agent)--a nonantiseptic liquid soap (control), an antiseptic hand rinse containing 60% isopropyl alcohol (IPA) with emollients (Alc A), an antiseptic hand rinse containing 70% IPA and 0.5% chlorhexidine gluconate with emollients (Alc B), an antiseptic containing 4% chlorhexidine gluconate and 4% IPA (CHG), and 70% IPA--washed their hands 15 times per day for 5 days under supervision by using a standardized technique and measured amounts of test agent. Microbiologic samples of hand flora were obtained at base line and after hand washes 1 and 15 on test days 1 and 5. After the initial hand wash there were significant reductions over base line in aerobic and anaerobic log CFU among those using Alc A, CHG, and IPA. By the end of the first day of hand washing (15 washes), there were 2-log or greater reductions in aerobic counts among subjects using all antiseptics, but no significant reductions in controls. By the end of day 5, all agents produced significant reductions in aerobic (P = 0.0002) and anaerobic (P = 0.002) counts over control soap. Subject assessment of effects of hand washing on the skin and overall satisfaction varied significantly by product (P = 0.04 and 0.05, respectively). We conclude that alcohol-based hand rinses are highly efficacious, and such products are recommended as a health care personnel hand wash, particularly when sink and running water are inaccessible.