MULTIDRUG-RESISTANT SALMONELLA-TYPHI - A WORLDWIDE EPIDEMIC

Since 1989, strains of Salmonella typhi resistant to chloramphenicol, ampicillin, and trimethoprim (i.e., multidrug-resistant [MDR] strains) have been responsible for numerous outbreaks in countries in the Indi an subcontinent, Southeast Asia, and Africa. MDR strains have also bee n isolated with increasing frequency from immigrant workers in countri es in the Arabian Gulf, as well as in developed countries from returni ng travelers. In all MDR strains so far examined, multiple resistance has been encoded by plasmids of the Il, incompatibility group. As a re sult of the widespread dissemination of such strains, chloramphenicol can no longer be regarded as the first-line drug for typhoid fever. Be cause strains are also resistant to ampicillin and trimethoprim, the e fficacy of these antibiotics has also been impaired, and ciprofloxacin is now the drug of choice for typhoid fever. Chromosomally encoded re sistance to ciprofloxacin has now been observed in a small number of s trains isolated in the United Kingdom from patients returning from the Indian subcontinent, and in at least one case the patient did not res pond to treatment with this antibiotic. It is regrettable that resista nce to ciprofloxacin has now emerged in MDR S. typhi, and it is of par amount importance to limit the unnecessary use of this vital drug so t hat its efficacy should not be further jeopardized.