Typhoid Fever
Typhoid fever, caused by Salmonella enterica serotype Typhi, is an infection of global importance with an estimated 21.5 million infections and 200,000 deaths per year (estimated in the year 2000). S. Typhi is a potential bioterrorist agent that could be disseminated in untreated water supplies and food, resulting in moderate morbidity and low mortality. Resistance to chloramphenicol, ampicillin and trimethoprim/sulfamethoxazole is widespread and resistance to the fluoroquinolones is currently spreading throughout Asia. Typhoid has been a target for vaccine development for decades and whole cell, live oral and subunit vaccines have been developed and proved both safe and efficacious. Two currently licensed vaccines are available but are not commonly used in endemic areas and the need for extensive vaccination programmes are of critical importance.