Emerg Infect DiseidEmerging Infectious Diseases1080-60401080-6059Centers for Disease Control96212062640144Research ArticleMolecular fingerprinting of multidrug-resistant Salmonella enterica serotype Typhi.HamptonM. D.WardL. R.RoweB.ThrelfallE. J.Central Public Health Laboratory, London, United Kingdom.Apr-Jun199842317320

For epidemiologic investigations, the primary subdivision of Salmonella Typhi is vi-phage typing; 106 Vi-phage types are defined. For multidrug-resistant strains the most common types have been M1 (Pakistan) and E1 (India, Pakistan, Bangladesh, and the Arabian Gulf); a strain untypable with the Vi phages has been responsible for a major epidemic in Tajikistan. Most often, isolates from the Indian subcontinent have been resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides, tetracyclines, and trimethoprim; but in the 1997 Tajikistan outbreak, the epidemic strain was also resistant to ciprofloxacin. For multidrug-resistant strains, subdivision within phage type can be achieved by plasmid profile typing and pulsed-field gel electrophoresis.