Certification Board of Infection Control and Epidemiology (CBIC) Practice Exam 2025 – The All-in-One Guide for Exam Success

The presence of hepatitis B surface antibodies, indicated by the positive result for HbsAB, is a definitive marker of immunity following hepatitis B vaccination. When a person is vaccinated against hepatitis B, the immune system responds by producing these antibodies, which serve as a protective mechanism against the virus. The presence of HbsAB in the blood signifies that the individual has effectively developed an immune response, indicating both protection from infection and the success of the vaccination.

Other markers listed do not indicate immunity from hepatitis B vaccination. For example, HbsAG refers to the hepatitis B surface antigen, which indicates active infection rather than immunity. Similarly, HbeAG is a marker of viral replication and infectivity, while HbcAB indicates previous or ongoing infection rather than a response to vaccination. Understanding these markers is crucial in assessing an individual’s immunity and managing potential health risks associated with hepatitis B.