This is a multicenter, prospective, real-world study. The study plans to include a total of 2000 patients who meet the inclusion and exclusion criteria, consisting of 1600 treatment-naive patients and 400 treatment-experienced patients. The effectiveness and safety of different treatment strategies will be evaluated in children aged 1-12 years with treatment-naive and treatment-experienced chronic hepatitis B (CHB) and chronic HBV infection.

Inclusion Criteria:

• Initial Treatment Group:

  1. The guardian understands and signs the informed consent form (both parents must sign), and adheres to the relevant requirements of this study. If the participant is 8 years old or older, they must also sign the informed consent form. For participants under 8 years old who can express consent, their consent must be clearly documented.
  2. Age: ≥1 year and <13 years, either sex;
  3. Positive for HBsAg and/or HBV DNA for more than 6 months;
  4. No prior antiviral treatment.

• Treated Group:

  1. The guardian understands and signs the informed consent form (both parents must sign), and adheres to the relevant requirements of this study. If the participant is 8 years old or older, they must also sign the informed consent form. For participants under 8 years old who can express consent, their consent must be clearly documented.
  2. Age: ≥3 years and <13 years, either sex;
  3. Previously diagnosed with chronic hepatitis B and received antiviral treatment with NAs for more than 1 year and currently on treatment;
  4. No history of IFNα use in the past 6 months;
  5. Negative for HBV DNA;
  6. HBsAg quantification <10,000 IU/ml (HBsAg can be negative in the drug discontinuation observation group);
  7. The drug discontinuation observation group must also achieve negative HBV DNA and HBeAg seroconversion for at least 1 year (based on continuous results from three consecutive reviews), and HBsAg <10,000 IU/ml; NAs will be discontinued after enrollment.

Exclusion Criteria:

• 1.In the interferon group, blood white blood cell count <3.5×10^9/L, or platelet count <80×10^9/L, or prothrombin activity <60%, or total bilirubin >34μmol/L, or serum albumin <35g/L, or serum creatinine >133μmol/L; 2.Coexistence of other active infections; 3. Coexistence of other chronic liver diseases or active liver diseases, such as autoimmune liver disease, drug-induced liver injury, Wilson's disease, decompensated cirrhosis, liver cancer; 4. Coexistence of other severe systemic diseases or malignant tumors, etc.; 5. History of allergy to nucleoside analogues or interferon; 6. Subjects whom the investigator deems to have poor compliance, unable or unwilling to provide informed consent, or unable to adhere to the study requirements, or other conditions not suitable for participation in this study.

The patients provided by hospitals from various centers across the country are standardized in English translation.