Valutazione della somministrazione di vitamina D sulla immunogenicità del vaccino trivalente inattivato contro influenza in bambini mai vaccinati

Considering that vitamin D (VD) exerts a significant regulatory effect on normal innate and adaptive immunity, in this prospective, randomized, single-blinded, placebo-controlled study the impact of VD administration on immune response to trivalent influenza vaccination (TIV) was measured. A total of 116 children with a history of recurrent acute otitis media (AOM), who were previously unvaccinated against influenza, were enrolled and randomized to receive daily VD 1,000 IU or placebo by mouth for 4 months. All of them received two doses of TIV (Fluarix, GlaxoSmithKline Biologicals, Rixensart, Belgium) one month apart. No difference was found between VD and placebo groups for any of the three influenza vaccine antigens in seroconversion rates as well as in seroprotection rates and antibody titres. Safety profile was also similar between the groups. These data indicate that the daily administration of 1,000 IU of VD for 4 months starting from the moment of the injection of the first dose of TIV does not significantly modify the antibody response evoked by influenza vaccine.