COMPUTERIZED IMAGE-ANALYSIS OF FULL-HAND TOUCH PLATES - A METHOD FOR QUANTIFICATION OF SURFACE BACTERIA ON HANDS AND THE EFFECT OF ANTIMICROBIAL AGENTS

A method is described for quantification of the bacterial flora on the hand surface. Computer-assisted image analysis of bacterial growth of large full-hand touch plates provides a quantifiable measure of the bacterial flora on the hand surface. Image analysis pixel intensity values showed a significant correlation (P < 0·0001) with colony forming unit values determined by the glove juice method. Image analysis of impressions from hands treated with various antimicrobial agents in detergent bases showed that 4% chlorhexidine gluconate produces a 96% reduction after a 30 s washing and 98% reduction after a 3 min washing while 7·5% povidone-iodine and 1% triclosan produce a 77% and 70% reduction after 3 min respectively, and 70% isopropanol produces a 98% reduction after a 30 s wash. © 1991.