Microbiological evaluation of two hand hygiene procedures achieved by healthcare workers during routine patient care: a randomized study.

The aim of this study was to evaluate the comparative microbiological efficacy of hand rubbing and handwashing in healthcare workers from different wards, with particular emphasis on transient flora, and to assess predisposing factors for hand contamination after patient care in everyday practice. Over a six-month period, 50 healthcare workers were randomly assigned, using a crossover design, to perform handwashing with unmedicated soap and hand rubbing with an alcoholic solution following a healthcare procedure. Imprints of palms and fingertips were taken separately before and after each hand hygiene procedure. The number of colonies per plate was counted and transient pathogens were identified. Risk factors for hand contamination were determined. Hand rubbing produced a significantly greater reduction in microbiological load than handwashing (P<0.0001 for palms and P=0.0003 for fingertips). In multivariate analysis, working in a medical ward rather than in an intensive care unit was significantly associated with increased hand contamination (P=0.03 for palms and P=0.02 for fingertips). Transient pathogens were found on 15% of healthcare workers' hands before hand hygiene. The only factor associated with hand contamination by transient pathogens was the absence of gloving during the healthcare procedure (odds ratio 4.8; 95% confidence interval 1.2-19; P=0.03). After hand rubbing, no transient pathogens were recovered, while these were found in two cases after handwashing. Hand rubbing is more efficacious than handwashing for the decontamination of healthcare workers' hands following contact with patients and patients' environments. Gloving may reduce microbiological hand contamination by transient pathogens.