There are three commercially available vaccines against typhoid fever: parenteral inactivated whole cell vaccine, oral live attenuated (strain ty21a), parenteral polysaccharide vaccine (capsular antigen-Vi). Their protective efficacy is 50 to 88% (inactivated vaccine), 50 to 96% (live attenuated vaccine) and 75 to 80% (polysaccharide vaccine). The frequency of notable adverse reactions with the inactivated vaccine justifies the use of the new vaccines.