[Long term effectiveness of vaccination of Hepatitis A]

To develop a dynamic model of Hepatitis A transmission in order to predict the long-term effectiveness of Hepatitis A vaccination on 18 months old infants and 2 to 18 years old children.

A dynamic model of HA (S-E-I-R-V) was developed using the software Berkeley-Madonna. The parameters required for the model derived from literature. A sensitivity analysis was performed to assess the stability of the model through changing parameters.

During the period of 2010 to 2030, the cumulative cases of Hepatitis A would reach 7.8 million with an incidence of 38.8 per 100,000 without vaccination. With 38% to 57% coverage of vaccination in children of 1.5-18 years old, the cumulative cases would decrease to 4.36-4.75 million with an incidence of 17.5-19.4 per 100,000. The vaccination was predicted to reduce 3.06-3.45 million Hepatitis A cases with an incidence reduction of 19.4-21.3 per 100,000. This suggests that Hepatitis A vaccination would achieve a 54% decrease in incidence of Hepatitis A. The sensitivity analysis showed that the coverage of vaccination had a significant impact on the incidence of Hepatitis A. By 2030, the incidence of Hepatitis A would decrease from 19.4 per 100,000 to 16.0 per 100,000 when the vaccination coverage increases from 38% to 90%.

Hepatitis A vaccination can effectively prevent and control the incidence of Hepatitis A.