Seroepidemiology of hepatitis B in Greek children 6 years after the implementation of universal vaccination.

The seroepidemiology of hepatitis B in children living in Greece 6 years post-implementation of universal infant immunization (1998) was studied. We collected 90-100 sera/year of age, stratified by geographic region. The prevalence of HbsAg(+) was 0.6% (95% CI 0.3-1.3) whereas 4.5% (95% CI 3.4-5.9%) of children over 12 months of age had evidence of past HBV infection. A significant decline in the prevalence of past infection between children born before and after 1998 (5.5% vs 2.9%; RR = 1.9, 95% CI 1.03-3.5) was noted. Conversely, the prevalence of past HBV infection did not change significantly among immigrant children. Reinforcement of early vaccination of immigrant population is necessary.