Evaluation of the long term effects of treatment with peginterferon alfa-2a plus ribavirin for patients with chronic hepatitis C/ hepatitis B co-Infection and chronic hepatitis C in the original study ML17862 is important. This present protocol is thus to assess whether the HCV SVR is sustained and to assess the durability of the HBV virologic and serologic responses or any incremental response during a 5-year follow-up period, including six months after end of the therapy in the original study and an additional 4 and half years in this project (5 years overall follow-up after the end of treatment). Specifically, we wish to assess the (1) sustained virologic response (SVR) of HCV in both populations, (2) incidence of HBsAg loss and HBsAg seroconversion (HBsAg loss and appearance of anti-HBs) in dually infected population, (3) ALT normalization or flare off-treatment during both populations, (4) reductions of HCV RNA from the original baseline levels in the two patient populations, and (5) reduction of serum HBV DNA off-treatment in the dually infected population.