- Positive serology for Hepatitis B (HB) defined as a positive test for HBsAg (the surface antigen of the Hepatitis-B-Virus). In addition, if negative for HBsAg but HBcAb (Hepatitis B core Antibody) positive (regardless of HBsAb status), a HB DNA test will be performed and if positive the subject will be excluded. Consent will be sought prior to any test being performed.