The surivival of Staphylococcus aureus on human skin. An investigation using mixed cultures.

In a study of the survival of on human skin, the application of mixed cultures of organisms was used to minimize variations due to host and environmental factors. The numbers of staphylococci recoverable from the skin fell rapidly during the 5 hr after inoculation. The rates of disappearance were similar on skin and on glass, and partly depended on the relative humidity of the atmosphere. Thus, desiccation appeared to be the main agent of removal of staphylococci from the exposed skin under the condition of the experiments. The production of lipase by the organism was not significantly correlated with its survival. In contrast to previous experiments in which the inoculated skin was occluded, elimination of staphylococci by skin lipid could not be demonstrated. Some strains of consistently survived longer than others on skin, and as a group, strains obtained from furunculosis survived better than strains from other sources. The ability to survive on the skin may be a factor that determines the predominance of some strains in cutaneous lesions. Strains of phage-group III survived less well on skin and on glass than other strains. This may be why multi-resistant Group III strains have not become more widespread in the community outside hospitals.