This project is based on the potential of conjugated vaccines to induce a long-lasting and effective immune response in infants, which differentiates them from polysaccharide vaccines. The evaluation in animal models of conjugates using the Vi polysaccharide of Salmonella Typhi and the tetanus and diphtheria toxoids as carrier proteins, has shown the induction of a high immune response as well as the production of B and T cells related to immunological memory.