Chapter 27 : Antibiotic Resistance in Salmonella and Shigella

Abstract:

Resistance to antimicrobial drugs, and particularly multidrug resistance, is a major problem in Enterobacteriaceae in both developing and developed countries throughout the world, affecting a wide range of genera, including Salmonella enterica, Shigella species and Escherichia coli. This chapter concentrates specifically on S. enterica and Shigella species. The most important serovars in the United Kingdom and Europe are Enteritidis and Typhimurium and in the United States are Typhimurium, Enteritidis, and more recently, Newport. In the United Kingdom for the last four decades, the history of multiple resistance in S. enterica has been dominated by three major clones of serovar Typhimurium, namely definitive phage types (DTs) 29, 204/204c/193, and 104. Whatever the outcome, the increased occurrence of strains of enterica with resistance to fluoroquinolones and/or third-generation cephalosporins in many different countries is an alarming development, which has already had fatal consequences. The main method of transmission is by person-to-person spread either in hospitals or in the community. The first major outbreak was that which occurred in Central America from 1969 to 1972, and the strain was resistant to chloramphenicol, streptomycin, sulphonamides, and tetracyclines (R-type CSSuT). The second major international outbreak occurred in Central Africa from 1979 to 1982. Multiple drug resistance is now common in pathogenic gut bacteria in both developing and developed countries throughout the world. The rapid emergence of resistance to the drugs of choice for diseases such as typhoid fever and bacillary dysentery is of particular concern.