Clinical studies have proven the efficacy and persistence of Hibiclens Antiseptic/Antimicrobial Skin Cleanser. A study demonstrated this by using agar plates inoculated with Staph aureus. Hands were washed daily for five days with Hibiclens, and then pressed onto the inoculated plates # palms down. The plates were then incubated and a whitish Staph aureus lawn grew in areas unaffected by antiseptic activity. Hand prints on plates touched by Hibiclens-washed hands remained clear and unaffected by the whitish Staph aureus lawn, showing immediate kill and a cumulative effect that didn't know when to quit. In fact, this demonstration showed that Hibiclens was still killing on the fifth day of use - 6 hours after the final daily hand wash.