Antibody

Quest Diagnostics

Print

COVID-19

Quest Diagnostics

Antibody blood test for COVID-19

Antibody testing detects if you have antibodies from a prior or recent COVID-19 infection. Positive results may occur after COVID-19 vaccination, but the clinical significance of antibody results for individuals that have received a COVID-19 vaccine is not yet known.*

Key Feature

Know your antibody status

Typical Results Turnaround

from sample pickup

1-2 days

Test Method

Blood test collected at a Quest location

*It is not yet known how effective this test is at detecting antibodies in those that have been vaccinated. Additionally, how long antibodies remain detectable after infection or vaccination and how long protection, if any, may last is also not known. The results of this test should not be interpreted as an indication of degree of immunity or protection.

How to get the test

Start by either purchasing a test through QuestDirect, or by asking your healthcare provider to order a test for you. Once you have your test order, make an appointment to have your sample collected at a Quest Patient Service Center.

KNOW your antibody status

Understanding your antibody status gives you powerful insight into your health.

Waiting for the vaccine

Find out if you had a prior or recent COVID-19 infection and already have some level of antibodies.

Already have antibodies

Track evidence of your antibodies over time. You can do this by getting the same antibody test at regular intervals from the same lab provider.


Discuss any test results with your doctor. It is also still important to follow the latest guidance from your community and the CDC.

Test tube illustration

Who can get antibody testing

Antibody testing is available only to those who are not currently experiencing COVID-19 symptoms and have not experienced symptoms for at least 10 days.

Common COVID-19 symptoms include fever, cough, and shortness of breath.

See FAQs

Continue to protect yourself

It is not yet known how effective this test is at detecting antibodies in those who have been vaccinated. Additionally, it is also not known how long antibodies remain detectable after infection or vaccination and how long protection, if any, may last. The results of this test should not be interpreted as an indication of degree of immunity or protection.

COVID-19 is highly contagious, and you should continue to practice preventive measures to protect yourself and others, regardless of your antibody level.

Get your results

When your sample is collected at a Quest Patient Service Center, your test results can be sent to you automatically through the secure MyQuest app. This is usually the quickest way to get results.

Don’t have MyQuest?
Sign up now to get your test results online.

launch myquest

Test tube illustration

Important information about COVID-19 antibody testing

This COVID-19 Antibody Test can detect antibodies from a prior or recent infection, regardless of whether symptoms were present. Positive results may also occur after a COVID-19 vaccination, but the clinical significance is not yet known, nor is it known how good this test is at detecting antibodies in those who have been vaccinated. Alternatively, a nucleocapsid test can only detect antibodies from a prior or recent infection.

After a natural infection, current research shows that it may be best to get antibody testing 3 to 4 weeks after symptom onset or known exposure to COVID-19 to increase the opportunity to detect an immune response.

After vaccination, it is not yet known how long it takes to develop antibodies. Antibody testing for the purposes of vaccine decision-making is not currently recommended by the CDC.

If you test too soon, your body may not have produced enough antibodies to be detected by the test, which can lead to a false negative result. This test can sometimes detect antibodies from other related coronaviruses you may have been exposed to, such as a virus that causes the common cold. This can cause a false positive result.

This test should not be used to diagnose an active COVID-19 infection. If an active infection is suspected, molecular or antigen testing is recommended. Learn more about our QuestDirect COVID-19 Active Infection Test.

A negative antibody test result means that antibodies were not detected in your blood sample. This can have several possible meanings. It could mean that:

  • You have not been infected with SARS-CoV-2, or
  • You have been infected with SARS-CoV-2, but your antibodies have not reached a sufficient level for the test to be able to detect them, or
  • You have been infected with SARS-CoV-2, but there has not been enough time for antibodies to develop (it can take up to 1 to 3 weeks to develop antibodies after someone is infected, sometimes longer).

A positive antibody test result means that antibodies were detected in your blood sample.

This can have a couple of possible meanings. It could mean that:

  • You have been infected with SARS-CoV-2 at some point in the past, or
  • Uncommonly, you may have developed antibodies from an earlier infection with a different virus related to SARS-CoV-2 and the laboratory test cannot distinguish between these other virus antibodies and those antibodies generated in response to SARS-CoV-2.

Learn more about the CDC’s antibody testing guidelines.

COVID-19 testing statements

  • The antibody tests have not been FDA cleared or approved;
  • The antibody tests have been authorized by FDA under an EUA for use by authorized laboratories;
  • The antibody tests have been authorized only for the detection of IgG antibodies against SARS-CoV-2, not for any other viruses or pathogens; and,
  • The antibody tests are only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostics for detection and/or diagnosis of COVID-19 under Section 564(b)(1) of the Act, 21 U.S.C. § 360bbb-3(b)(1), unless the authorization is terminated or revoked sooner.

About the FDA Emergency Use Authorization (EUA) Status

This test has been authorized by the FDA under an Emergency Use Authorization (EUA). This means that while Quest Diagnostics has validated the test and has the data to believe the test and the collection kit are accurate, this test has not been FDA-cleared or -approved; This test has been authorized by FDA under an EUA for use by authorized laboratories; this test has been authorized only for the detection of IgG Antibodies against SARS-CoV-2, not for any other viruses or pathogens; and, this test is only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use on in vitro diagnostics for detection and/or diagnosis of COVID-19 under Section 564(B)(1) of the Act, 21 U.S.C. § 360BBB-3(B)(1), unless the authorization is terminated or revoked sooner. Additional studies need to be conducted for this test and others like it to be FDA cleared or approved.

Other COVID-19 test options