Antibody Test for COVID-19


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.

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.

Antibody testing is important because:

  • It could show who has already had COVID-19. These people might be safe to go back to work or school or to travel.
  • It could show who hasn't had the infection. These people are still at risk. They need to keep taking steps to avoid the virus.
  • It helps experts who are tracking COVID-19 learn more about the virus and how it spreads.

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.

Related Information


Current as of: December 18, 2020

Author: Healthwise Staff
Medical Review:
Heather Quinn MD - Family Medicine
Lesley Ryan MD - Family Medicine

Antibody Test for COVID-19