What it measures
Antibodies to the surface protein of the hepatitis B virus (anti-HBs). The body makes them after hepatitis B vaccination or after clearing an infection. The result is given as a level.
Why people test it
- Checking the response to hepatitis B vaccination, for example for healthcare or lab work.
- Checking immunity before travel or a job with contact with blood.
- Read with the core antibody test to tell vaccination apart from a past infection.
Typical range
Results are given as a number. North West London Pathology notes that 10 mIU/mL (the same as 10 IU/L) or more is generally accepted as protective. Cut-offs and methods vary by lab, and your report shows how the lab reads its result. Source: North West London Pathology: Hepatitis B surface antibodies.
Finger-prick or vein?
A finger-prick sample is usually fine for an antibody test like this, and some providers offer a home kit. Others take blood from a vein, at a clinic or with a visiting nurse.