COVID Testing


Antibody Testing

What is antibody testing?

  • Antibody testing is a blood test that detects evidence of a past infection with COVID-19. It can not be used to detect a current infection. Antibodies may be detected around 3 weeks after an infection.

What does it mean if I test positive?

  • A positive test may indicate a history of previous infection with COVID-19. It does NOT mean you are immune to the virus and it should not be used to discontinue social distancing and other safety measures.

  • In areas of low-prevalence or in persons with a low pre-test probability of having the disease (aka someone who had no symptoms, had no known exposures, and lives in a low prevalence place), the likelihood of a positive test being a false positive is higher.

What does it mean if I test negative?

  • A negative test may indicate that you have not been infected with COVID-19. However, people who have a history of infection may still test negative for two reasons. 1) The test was performed too soon and the antibody response is not yet high enough to be detected. 2) The antibodies in the blood have already waned or were never high and are not currently detectable. Therefore, even people with a known and confirmed history of COVID-19 infection may still have a negative test.