Immunogenicity and reactogenicity of a booster dose of a novel combined Haemophilus influenzae type b-Neisseria meningitidis serogroup C-tetanus toxoid conjugate vaccine given to toddlers of 13-14 months of age with antibody persistence up to 31 months of age.

Primary immunization with 3 doses of Hib-MenC-TT coadministered with DTPa-HBV-IPV induced antibodies that persisted up to the second year of life. The Hib-MenC-TT booster administered to primed toddlers induced robust and persistent antibody responses to both the Hib and MenC components and had an acceptable safety profile.