Antibody to Epstein-Barr Virus (EBV) Nuclear Antigen (IgG) - Serum

What Does This Test Measure?

The test detects IgG antibodies specific to the EBV nuclear antigen (EBNA), a protein found in the nucleus of infected cells. IgG antibodies are part of your immune system’s memory response and remain in your blood for years after infection. This test is used to identify whether you’ve had EBV at any point in your life.

Why Might You Need This Test?

Your healthcare provider may order this test if you have symptoms of EBV infection (e.g., fatigue, swollen lymph nodes, fever) or if you’re being evaluated for conditions linked to EBV, such as chronic fatigue syndrome, certain cancers (e.g., Burkitt lymphoma, nasopharyngeal carcinoma), or autoimmune diseases. It can also help monitor long-term immunity in individuals at higher risk.

How Is the Test Performed?

A blood sample is drawn from a vein in your arm. The serum portion of the blood is then tested in a laboratory using an immunoassay method to detect EBV-specific IgG antibodies. Results are reported as positive or negative, indicating the presence or absence of these antibodies.

What Do the Results Mean?

A positive result means you have IgG antibodies to EBV, suggesting past infection. A negative result indicates no detectable antibodies, which may mean you’ve never been exposed or the test was taken too early after infection. False negatives can occur if testing is done too soon after exposure.