Comparative in vitro and in vivo study of nine alcohol-based handrubs

Hygienic hand disinfection using alcohol-based handrubs (AHRs) is an alternative method to conventional handwashing in hospital wards. Because a documented choice of such products would consider data from in-care evaluation, we designed a comparative study of 9 AHRs both in vitro and in vivo in actual care conditions.

The bactericidal activity of AHRs was first measured in vitro against 4 hospital strains exhibiting multiple antibiotic resistance: Acinetobacter baumannii, Staphylococcus aureus, Pseudomonas aeruginosa, and Enterobacter aerogenes. In a second time, AHRs were tested in an intensive care unit for antibacterial activity against the cutaneous flora of personnel hands and for acceptance by the care personnel.

The 9 AHRs could be classified in 3 groups on the basis of their in vitro activity: products of the first group showed a bactericidal activity higher than 4 log(10) against the 4 strains. Only 1 of these products presented simultaneously an effective antibacterial activity against the cutaneous flora of care personnel hands and a good acceptance by the care personnel.

The in vitro study allowed the differentiation of the AHRs tested on the basis of bactericidal activity, but evaluation in an in-care situation allowed further discrimination through both antibacterial activity and acceptance. Thus, the combination of in vitro and in vivo evaluations should provide helpful arguments in the choice of AHRs.