Microbiological Sampling Techniques

Abstract

The purpose of microbiological sampling is to allow statements of density, types and locations of microorganism which reside on the skin. The problem is that different answers are given by different sampling techniques. In laboratory experiments microorganisms are grown in ideal homogeneous culture conditions and a single sample of the culture will reflect the entire culture. The human skin is a heterogeneous environment composed of many small homogeneous environments, often distributed in patterns which differ with site and individual. Since environment determines the microbial inhabitants (bacteria, fungi, viruses, protozoa and mites) their distribution on human skin varies from site to site and from person to person. In practice the investigator makes many compromises: simple techniques produce data of limited value whilst the complex techniques are restricted by the type of site that can be sampled and the number of samples that can be taken.