Ty21a is licensed for use from age six years and older. Boosters are recommended every 5 years. The Vi capsular polysaccharide vaccine is licensed for use from age two years and older, and boosters are required every three years.
Almroth Edward Wright developed an effective inactivated whole-cell typhoid vaccine that was introduced in 1896. Due to side-effects its usage was eventually discontinued.
^ abAnwar, E; Goldberg, E; Fraser, A; Acosta, CJ; Paul, M; Leibovici, L (2 January 2014). "Vaccines for preventing typhoid fever.". The Cochrane database of systematic reviews1: CD001261. PMID24385413.