CDC hepatitis B serology: understanding the blood tests

Serology commonly includes hepatitis B surface antigen, surface antibody, and core antibody. The pattern can suggest current infection, previous infection with immunity, immunity from vaccination, or no recognised immunity. One marker alone rarely gives the whole answer, and the timing of exposure or vaccination can change interpretation. A clinician may also check liver enzymes and other tests to understand whether the liver is inflamed and whether infection is recent or longstanding.

Take the complete report to a clinician rather than interpreting a single positive or negative line in isolation. Ask whether repeat testing, additional hepatitis B tests, vaccination, or a liver function test is appropriate. If infection is confirmed, avoid sharing razors or toothbrushes and discuss testing or vaccination for household and sexual contacts. The Hepatitis B Vaccination page explains prevention, while the Hepatitis B page covers the condition.

Arrange medical review promptly for a result suggesting current infection, a recent exposure, or symptoms such as fatigue or dark urine. Seek urgent help for confusion, severe vomiting, fainting, or yellow skin or eyes. A result that shows immunity is reassuring, but it does not replace assessment when symptoms or a new exposure are present.

Ask which markers were tested, whether the pattern indicates vaccination or infection, whether liver tests are needed, and how to protect people close to you.