Effect of high hepatitis B vaccine coverage on the incidence among inoculated populations

Objective To evaluate immunogenecity of high hepatitis B vaccine coverage. Methods We analyzed incidence and inoculation data of each year and detected the sero-prevalence by the method of ELISA for HBsAg, Anti-HBs, and Anti-HBc. Serologic results before and after the inoculation were compared to evaluate the effects of vaccine coverage. Results Since twenty years after hepatitis B vaccination (1992-2011), the incidence among children under 15 years old decreased by 86.84%. The peak of incidence among children of 5-14 years old was flattened. Carrier rate of HBsAg decreased from 13.59% in 1990 to 4.61% in 2006. It has fallen from a high popular area to a moderately popular area. Carrier rate of HBsAg among children under 15 years old decreased from 12.67% to 0.82% (decreased by 93.53%). Conclusions There is prominent immune protective effect of hepatitis B vaccine with high coverage, which should be maintained. Key words: Hepatitis B vaccine; Children under 15 years old; Immunogenecity