Pneumococcal Vaccination for Splenectomised Thalassemia Major Patients in Indonesia

This study is a single blinded randomised-control trial. Splenectomized thalassemia major patient samples were provided with PCV pneumococcal vaccine (Prevenar 13®) at the start of the trial, following which they were randomly assigned to 2 groups (zinc and placebo group). After 8 weeks, the subjects received PPV pneumococcal vaccine (Pneumovax®). Zinc syrup was provided to the zinc group at a dose of 1.5 mg/kg/day (maximum of 50 mg/day). Placebo containing sucrose syrup of the same form, taste, consistency and color was given to the other group. Everyone except the primary researcher are blinded to which of the treatment is placebo and which is actual zinc syrup. Pneumococcal IgG examinations were conducted at the start of the trial and after 12 weeks.

Sample size was measured using:

n1=n2=n= {((Zα+Zβ) Sd)/d}^2 where N = number of subject Za = degree of significance (5%), a = 5% Zb = strength of study (80%). b = 20% Sd = standard deviation d = meaningful difference between the two groups The measured sample size is 816, but due to limited patient total population sampling was used instead.