The plasmid pattern as an epidemiologic tool for Salmonella typhimurium epidemics: comparison with the lysotype.

In the study of a limited epidemic of Salmonella typhimurium infections, the plasmid content (pattern) of bacteria was used as an epidemiologic tool outside the hospital environment. Comparisons were made with lysotyping, resistance pattern determination (14 antibiotics), and biotyping. Plasmid pattern determination was found to be as useful and accurate as lysotyping, whereas resistance pattern determination was of more limited interest. However, in this report biotyping was of no use.