Antibody Test for COVID-19

Overview

An antibody test looks for antibodies in the blood. These are proteins that your immune system makes, usually after you're exposed to germs like viruses or bacteria or after you get a vaccine. Antibodies work to fight illness.

A COVID-19 antibody test looks for antibodies to SARS-CoV-2, the virus that causes COVID-19. If you test positive for these antibodies, it could mean that you already had COVID-19 or that you've been vaccinated for COVID-19.

This test can be used to diagnose a past infection with the virus that causes COVID-19. Many people who get COVID-19 never have symptoms or have only mild ones. Without antibody testing, these people might never know that they already had the virus. Even if the test shows that you may have had COVID-19, you need to keep taking steps to protect yourself and others from the virus. Having COVID-19 in the past may not prevent you from getting it again.

Antibody testing is important because:

• It could show who has already had COVID-19.
• It could show who hasn't had the infection.
• It helps experts who are tracking COVID-19 learn more about the virus and how it spreads.

Talk to your doctor about what the test results mean for you.

This is a blood test. A health professional may prick your finger or use a needle to take a sample of blood from your arm.