Seroconversion after recombinant hepatitis B vaccination

Background: hepatitis b virus infection is an important public health problem with significant morbidity and mortality. recombinant hepatitis b vaccine for the prevention of hepatitis b virus infection is in practice in different parts of the world since its availability in 1986. government of bangladesh has also included hepatitis b vaccine in epi schedule since 2005. materials and methods: this study was carried out to assess the seroconversion status among hepatitis b vaccinated individuals. a total of 190 individuals including 150 vaccinated persons and 40 non-vaccinated apparently healthy individuals were included as study population. sources of vaccinated persons were from both epi and non-epi schedule of vaccination. age and sex matched non-vaccinated individuals served as controls for the study. all individuals constituting the study population were screened for hbsag by immunochromatographic strip test and only hbsag-negative persons were included for estimation of their anti-hbs titer. results: out of 150 vaccinated individuals,133(88.67%) were found to have anti-hbs titer in the protective level (>10 iu/l),while 17(11.33%) individuals had anti-hbs titer below the protective level (<10 iu/l). all non-vaccinated controls had anti-hbs titers below the protective level. regarding immune response developed among vaccinated individuals,67.78%,23.33% and 8.89% were good-responders,hypo-responders and non-responders respectively. mean titer of anti-hbs was found significantly higher among recipients who received booster dose than those who received 3 doses schedule (863.39 iu/l vs. 262.40 iu/l),indicating high antibody titer develops after booster dose. vaccinated group included 85 (56.67%) men and 65 (43.33%) women with protective level of anti-hbs titer found in 85.88% male and 92.31% female individuals. there was no significant difference of anti-hbs titer between male and female (p>0.05). vaccinated individuals from lower socioeconomic condition have had comparatively low rate of protective antibody than people from middle and upper classes. conclusion: recombinant hb vaccine induces good level of protective immunity among vaccinated persons.