RESUMO
Thalassemia patients, comparing to normal population are more susceptible to hepatitis, because of frequent blood transfusions. To determine the immune response of children with major beta-thalassemia, by measuring anti-hepatitis B surface antibody [anti-HBs Ab] following the last HBV vaccine injection. This study carried out on 215 thalassemic children who received three st and ard intramuscular recombinant HBV vaccines. Children age range was between 1- 4.5 with a mean age of 3.37 years. Based on the time lapsed since last vaccine injection, the subjects were divided into three groups; 0-15 months, 15-30 months and 30-45 months, respectively. Based on the serum levels of anti-HBs antibody, subjects were categorized as: good responders [anti-HBs >100 IU/Lit], low responders [anti-HBs 10-100 IU/Lit] and non responders [anti-HBs <10 IU/Lit]. The mean range of anti-HBs level in the above mentioned groups were 205.34, 128.8 and 54.25 IU/lit, respectively [P<0.0001]. In girls, the mean antibody level was 104.2 and in boys it was 95.8 IU/Lit [P>0.05]. Out of 215 selected individuals 75 [35%] were good responders, 65[30%] low responders and 75 [35%] non-responders. St and ard HBV vaccination in thalassemic children results in an immune response in more than 65% of the subjects. Therefore, assessment of anti-HBs antibody level, 45 months after the last vaccination is recommended