Objective      To explore the long-term trends of hepatitis B in China and evaluate the current control measures implemented by the Chinese government.       Methods      A dynamic model was first proposed

and the reported data by the National Health and Family Planning Commission of the People’s Republic of China is fitted to obtain the estimations of model parameters and corresponding basic reproduction number. Then the sensitivity analysis was performed by Latin hypercube sampling and the partial rank correlation coefficient.       Results      The basic reproduction number was estimated as 0.671 2 (95% CI： 0.659 1-0.6

71 8)

which indicated that the epidemics of HBV was under control by the existing prevention and control measures. The sensitivity analysis results showed that there were 6 significant parameters with significant impact on the basic reproduction number

and according to the intensity from top to bottom

they were the transmission coefficient of acute infectious(β)

rate of waning vaccine-induced immunity (ψ)

vaccination rate (γ

3

)

reduced transmission rate of carriers (ε)

average probability that an acute infection fails to clear and become a carrier (q)

and rate moving from carriers to immune crowds (γ

2

).       Conclusion      The current prevention and control measures have played an active role in controlling the prevalence of HBV infection

and the effect of the carriers is larger than that of acute infection patients. Strengthening the health education to reduce the risk of infection and implementing strict policies of HBV vaccination are the focus to further reduce hepatitis B epidemics in China.