Influenza Vaccine Booster Stimulates Antibody Response in Beta Thalassemia Major Patients

The aim of this study was to evaluate antibody response against influenza vaccine in beta thalassemia major patients from Iran. Thirty beta thalassemia major patients were enrolled and divided into three groups: single dose (group 1), double dose (group 2), and control (group 3). Seroconversion, seroprotection, and geometric mean titer (GMT) assays were performed through hemagglutination inhibition (HI) on days 0, 14, and 60. Based on the results, the level of antibody titer was increased in group 2. Two weeks after vaccination, seroconversion rate was about 20% and 30% in groups 1 and 2. Sixty days after vaccination, the seroconversion rate was around 70% and GMT showed a more than 2-fold increase in group 2. Based on the results, the immunogenicity of double dose vaccination against influenza infection appears to be higher than the single dose vaccine in beta thalassemia major patients, and thus it is recommended to use two doses of vaccine, especially in splenectomized patients who are more sensitive than others.