Post-marketing Surveillance of Children With Chronic Hepatitis C Treated With Intron A (Vial or Pen) and Rebetol (Study P04397)(TERMINATED)

Inclusion Criteria: * Patients with chronic hepatitis C (serum HCV-RNA-positive) * Age 3 to 17 years * Treatment-naïve * Platelets \>= 100,000/mm\^3 * Neutrophil counts \>= 1,500/ mm\^3 * TSH must be within normal limits * Hemoglobin \>=12 g/dL (females); \>=13 g/dL (males) * Women of childbearing potential must have a routine pregnancy test performed monthly during treatment and for 7 months thereafter. Sexually active female subjects of childbearing potential must be practicing adequate contraception (intrauterine device, oral contraceptives, implanted contraceptives, surgical sterilization, barrier method, or monogamous relationship with a male partner who has had a vasectomy or is using a condom (+ spermicide) during the treatment period and for 7 months after stopping treatment. * Sexually active male subjects must be practicing acceptable methods of contraception (vasectomy, use of condom + spermicide, monogamous relationship with a female partner who practices an acceptable method of contraception) during the treatment period and for 7 months after stopping treatment. Exclusion Criteria: * Contraindications according to the SPC and European approval * Pretreatment of chronic hepatitis C * Liver decompensation * Hypersensitivity to the active substance or to any interferons or to any of the excipients * Pregnant woman * Woman who are breast feeding * Existence of or history of psychiatric condition, in particular depression, suicidal ideation or suicide attempt * A history of severe pre-existing cardiac disease, including unstable or uncontrolled cardiac disease in the previous six months * Severe debilitating medical conditions, including patients with chronic renal failure or creatinine clearance \< 50 mlLmin * Autoimmune hepatitis or history of autoimmune disease * Severe hepatic dysfunction or decompensated cirrhosis of the liver * Pre- existing thyroid disease unless it can be controlled with conventional therapy * Epilepsy and/or compromised central nervous system function * Individual decision of physician if patient suitable for treatment (e.g., disturbance of growth)