typhoid conjugate vaccine

Typhoid conjugate vaccine (TCV) is a vaccine used to prevent typhoid fever, caused by the bacterium *Salmonella enterica* serovar Typhi. TCVs are composed of the Vi capsular polysaccharide antigen of *S. Typhi* chemically linked (conjugated) to a carrier protein, such as tetanus toxoid (TT), diphtheria toxoid (DT), or CRM197. This conjugation process enhances the immunogenicity of the polysaccharide by recruiting T-cell help, which leads to a more robust immune response, higher antibody titers, and the induction of immunological memory. Unlike the older Vi polysaccharide vaccines, TCVs are effective in infants and young children (from 6 months of age) and provide longer-lasting protection. Several TCVs have been developed through collaborations between the International Vaccine Institute (IVI) and various manufacturers, with Bharat Biotech's Typbar-TCV being the first to receive WHO prequalification in 2017.

Brand names

Typbar-TCVTYPHIBEVZyVac TCV

Other names

TCVTyphoid Vi-conjugate vaccineVi-conjugate vaccine