BACKGROUND: @entity1 6 through 35 months of age are recommended to receive half the dose of @entity683 vaccine compared with older @entity1 and adults. METHODS: This was a 6-site, randomized 2:1, double-blind study comparing full-dose (0.5 mL) trivalent inactivated @entity683 vaccine (TIV) with half-dose (0.25 mL) TIV in @entity1 6 through 35 months of age. @entity1 previously immunized with @entity683 vaccine (primed cohort) received 1 dose, and those with no previous @entity683 immunizations (naive cohort) received 2 doses of TIV. Local and systemic adverse events were recorded. Sera were collected before immunization and 1 month after last dose of TIV. Hemagglutination inhibition antibody testing was performed. RESULTS: Of the 243 subjects enrolled (32 primed, 211 naive), data for 232 were available for complete analysis. No significant differences in local or systemic reactions were observed. Few significant differences in immunogenicity to the 3 vaccine antigens were noted. The immune response to H1N1 was significantly higher in the full-dose group among primed subjects. In the naive cohort, the geometric mean titer for @entity5953 antigens after 2 doses of TIV were significantly higher in the 12 through 35 months compared with the 6 through 11 months age group. CONCLUSIONS: Our study confirms the safety of full-dose TIV given to @entity1 6 through 35 months of age. An increase in antibody responses after full- versus half-dose TIV was not observed, except for H1N1 in the primed group. Larger studies are needed to clarify the potential for improved immunogenicity with higher vaccine doses. Recommending the same dose could simplify the production, storage, and administration of @entity683 vaccines.

Safety and Immunogenicity of Full-Dose Trivalent Inactivated Influenza Vaccine (TIV) Compared With Half-Dose TIV Administered to XXXX 6 Through 35 Months of Age.

@entity1 :: ('9606', 'Species') :: ['children', 'Children'] @entity683 :: ('MESH:D007251', 'Disease') :: ['influenza'] @entity5953 :: ('5079', 'Gene') :: ['all 3']
@entity1 :: (9606,Species) :: ['Children']
