Seroepidemiology of hepatitis A among Greek children indicates that the virus is still prevalent: Implications for universal vaccination.

A national cross-sectional seroprevalence survey was conducted in order to evaluate the current seroepidemiology of hepatitis A among 1,383 children, aged 0-14 years, residing in Greece. Stratification of the study population was conducted according to age and area of residence. Sera from study participants were tested for the presence of anti-HAV IgG antibodies. Immigrant children, as well as children residing in rural areas, had lower immunization rates. Among unvaccinated children, the seroprevalence rate of anti-HAV was 17.1%. Nationality was shown to have a marginally significant effect since non-immunized immigrant children had a higher seroprevalence rate (22.4% vs. 15.9%, OR = 1.52, P = 0.064). Significant differences between geographic areas for both vaccination coverage and natural immunity were observed. The study findings indicate that hepatitis A is prevalent in Greece and therefore universal infant hepatitis A immunization should be implemented.

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.