Attempts to establish phage typing as an epidemiological marker for Salmonella enteritidis.

The notable increase in the number of Salmonella enteritidis strains seen in Spain in recent years (from 27.10% in 1980 to 66.36% in 1985) makes it necessary to find an additional epidemiological marker for this serotype. Phage typing was considered because of its discriminatory capacity toward other Salmonella serotypes. Wild and lysogenic bacteriophages were sought for a set of autochthonous bacteriophages. Our set consisted of 6 bacteriophages, 5 wild and 1 lysogenic. When tested on 1,500 selected strains, they produced 9 different phage types. The most abundant phage types were A (74.66%) and B (19.73%). The percentage of non-typable strains was low: only 1.4% from a total of 1,500 strains failed to produce lysis with our set. This reflects the high typability of the bacteriophage set proposed.