Occurrence of Gram-positive Organisms Possessing Characteristics Similar to Those of Salmonella and the Practical Problem of Rapid and Definitive Salmonella Identification.

The occurrence and incidence of gram-positive organisms which possess some biochemical and serological characteristics in common with salmonellae are described. These organisms were encountered as contaminants in various food products as well as in feces. Their growth in various Salmonella enrichment media, typical Salmonella-like growth on differential selective media, biochemical similarities to Salmonella, and agglutination in Salmonella polyvalent O antiserum serve as a source of possible confusion in analyses for Salmonella. Although a definitive identification was not performed, preliminary results indicate that these bacteria closely resemble members of the genus Brevibacterium. No sanitary significance could be associated with these bacteria, because they were never found to coexist with Salmonella. The occurrence of these bacteria illustrates the pitfalls of a cursory examination for Salmonella. On the premise that ultimate identification of Salmonella rests upon serological procedures, a rapid and definitive identification of suspect Salmonella isolates is proposed, based upon reactions with polyvalent group O, group O, and Spicer-Edwards H antisera.