The REACH-B study establishes an observational cohort study of people living with chronic hepatitis B from a national network, including a diverse range of services, to characterise and monitor hepatitis B linkage to care and treatment requirements amongst this population.

Participants presenting to participating clinics for HBV care within the previous 12 months will be identified and enrolment data will be collected including demographics, laboratory parameters, liver disease assessment, treatment history and clinical management. Follow-up data on HBV treatment and clinical management, liver disease stage and laboratory parameters will be collected at each subsequent visit or at minimum every 12 months.

Inclusion Criteria:

1. All individuals diagnosed with chronic hepatitis B in the participating study sites are eligible to be included (both newly diagnosed cases and those diagnosed in the past).
2. 16 years of age or older.
3. Attended the health service for HBV care within the prior 12 months from study commencement (retrospective recruitment) OR Attending the health service for HBV care from study commencement (prospective recruitment)

Exclusion Criteria:

1. Nil

Adults diagnosed with chronic HBV as defined by a positive HBsAg result at participating sites will be enrolled in the cohort. Participants can be newly diagnosed or existing patients of the service. Data on HBV disease status, liver disease status, HBV monitoring and treatment will be collected six monthly from enrolment.