Hepatitis B Core Antibody (IgG) – Serum/Plasma

What Does This Test Measure?

The test measures **IgG antibodies** against the hepatitis B core antigen. These antibodies develop after your immune system has encountered the virus, either from past infection or vaccination. IgG antibodies typically persist long-term, unlike IgM, which appears early in infection and fades over months.

Why Is This Test Done?

Doctors may order this test to evaluate hepatitis B status in people who have had hepatitis B exposure, those with chronic liver disease, or those with unexplained liver issues. It can also be part of screening for hepatitis B in high-risk groups.

When Might You Need This Test?

You might need this test if you’ve been exposed to hepatitis B (e.g., through medical procedures, sexual contact, or sharing needles), if you have chronic liver problems, or if you’re pregnant (to check for hepatitis B transmission risks). Some blood banks also use it to screen donated blood.

What Does a Positive Result Mean?

A positive result means your body has produced IgG antibodies against hepatitis B core antigen, suggesting either past infection (even if symptoms were mild or absent) or successful vaccination. This does not mean you’re currently infected but indicates immunity.