Immunity to Hepatitis B Vaccine in Thalassaemic Patients based on the Time Passed from Vaccination

Hepatitis B virus is one of the causes of acute and chronic hepatitis. Due to multiple hospitalization and blood transfusion, thalassaemic patients are at higher risk of this infection. Duration of the immunity after vaccination in this high-risk group and the need for booster vaccination is uncertain. The aim of this study was to find antibody titration and immunity to Hepatitis B vaccine in thalassaemic patients at different time intervals after vaccination. A total of 454 thalassaemic patients in Kerman were evaluated in this study. All patients had been vaccinated with recombinant hepatitis B vaccine according to the national vaccination program. On the base of the time interval after vaccination, patients were divided into the 6 groups of 1 year, 1-2, 2-3, 3-4, 4-5 and ≥5 years. According to their anti-HBs antibody titer, patients were classified as non-immune (<10 IU/L), semi-immune (10-100 IU/L) and complete-immune (>100 IU/L). The rates of non-immune cases in the 6 considered groups were respectively 3.28%, 3.3%, 5.7%, 19%, 33.3% and 58.2%. Three years after Hepatitis B vaccination in thalassaemic patients anti-HBs antibody levels decreases significantly. Therefore, evaluation of hepatitis B immunity level and performing booster vaccination after this period should be considered.