Access HBV Assays - European Union (EU) Clinical Trial Protocol -

Inclusion Criteria: * Subject aged ≥ 18 years, * Subject who has provided consent (oral or written) or sample collected under waiver * With sufficient volume to perform clinical trial testing * And belonging to one of the following enrollment groups: * Unselected blood donors * Hospitalized patients * Presumed HBsAg positive patients by Confirmatory testing of a CE-marked assay * Patients having recovered from natural HBV infection, presumed Anti-HBs positive (i.e. Anti-HBs and Anti-HBc Total positive by CE-marked assays) * Patients having received HBV vaccination, presumed Anti-HBs positive (confirmed by testing at the time of enrollment, i.e. positive for Anti-HBs and negative for Anti-HBc by CE-marked assays). * Presumed Anti-HBc Total positive patients by a CE-marked assay * Presumed Anti-HBc IgM positive patients by a CE-marked assay with acute/recent HBV infection 8 * Presumed HBeAg positive patients by a CE-marked assay * Presumed Anti-HBe positive patients by a CE-marked assay * Patients with chronic HBV infection Exclusion Criteria: * Samples from subjects already included in the study\* (\* Patient can be included only once per HBV marker study, but can potentially be enrolled for several separate HBV marker studies.)