Submitted to: Foodborne Disease Handbook
Publication Type: Book / Chapter
Publication Acceptance Date: January 9, 1999
Publication Date: N/A
Technical Abstract: Salmonella are gram-negative bacteria belonging to the family Enterobacteriaceae. These bacteria are widely distributed throughout various ecological habitats, having been isolated from soil, water, foods and the intestinal tracts of man and animals. The propensity of all Salmonella to cause systemic or enteric infections in man and animals make them important pathogens and despite many hygienic improvements in food production, these remain among the most important causative agents of foodborne disease. Manifestation of disease can be varied depending on the serotype and host. Techniques, including nucleic acid and immunological based methods, have been developed to detect and (or) isolate Salmonella from various specimens but bacteriological cultivation remains most used. Serotype, biotype, and phage type are all determinants of host-range and virulence. Individual isolates vary in virulence, biochemistry, susceptibility to bacteriophage, and in plasmid content. As alluded to previously, acquisition of additional genetic elements such as lysogenic phage (temperate phage or prophage) and extrachromosomal elements (plasmids) by a particular bacterium can bring about changes in phage type, serotype, and virulence.