Considerations regarding mass vaccination against typhoid fever as an adjunct to sanitation and public health measures: Potential use in an epidemic in Tajikistan

We report on the ongoing epidemic of typhoid fever in Tajikistan that start ed in 1996. It has involved more than 24,000 cases to date, and is characte rized by multiple point sources, overflow of sewage, contaminated municipal water, and person-to-person spread. Of the Salmonella typhi isolates avail able for testing in western laboratories, more than 90% are multidrug-resis tant (MDR). Most recently, 28 (82%) of 34 isolates are resistant to ciprofl oxacin, representing the first reported epidemic of quinolone-resistant typ hoid fever. In the past, mass immunization during typhoid fever epidemics h as been discouraged. A review of this policy is recommended in light of the alarming emergence of quinolone-resistant strains of S. typhi, the availab ility of improved vaccines, and the ongoing epidemic in Tajikistan. Mass im munization may be a useful measure for the control of prolonged MDR typhoid fever epidemics, as an adjunct to correction of municipal infrastructure a nd public health intervention.