MOLECULAR FINGERPRINTING OF MULTIDRUG-RESISTANT SALMONELLA-ENTERICA SEROTYPE TYPHI

For epidemiologic investigations, the primary subdivision of Salmonell a Typhi is viphage typing; 106 Vi-phage types are defined. For multidr ug-resistant strains the most common types have been M1 (Pakistan) and El (India, Pakistan, Bangladesh, and the Arabian Gulf); a strain unty pable with the Vi phages has been responsible for a major epidemic in Tajikistan. Most often, isolates from the Indian subcontinent have bee n resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides , tetracyclines, and trimethoprim; but in the 1997 Tajikistan outbreak , the epidemic strain was also resistant to ciprofloxacin. For multidr ug-resistant strains, subdivision within phage type can be achieved by plasmid profile typing and pulsed-field gel electrophoresis.