Escherichia,Shigella, andSalmonella

This chapter provides information on taxonomy, epidemiology, transmission, and clinical significance of genus Escherichia, Shigella, and Salmonella. It covers two well-recognized pathogenic groups or pathotypes, namely uropathogenic E. coli and meningitis/sepsis-associated E. coli and five categories of recognized diarrheagenic E. coli: Shiga toxin-producing E. coli, enterotoxigenic E. coli, enteropathogenic E. coli, enteroaggregative E. coli, and enteroinvasive E. coli. Describing process steps in collection, transport, and storage of specimens, the chapter discusses the process involved in direct examination, isolation, identification, genotyping, serologic testing, and antimicrobial susceptibility testing of these species, along with evaluation, interpretation, and reporting of results.