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5 things to know about SARS-CoV-2 (COVID-19) antibody testing with Quest

   We’re now offering an IgG antibody test that helps to identify people who may have been previously exposed to SARS-CoV-2 and may have developed an adaptive immune response to the virus. At this time, it is unknown for how long antibodies persist following infection and if the presence of antibodies confers protective immunity. Immunoglobulin (IgG) testing provides insight into an individual’s prior exposure to SARS-CoV-2, which may help to identify people who may be able to resume work and other daily activities in society. While the role of antibodies in preventing COVID-19 disease has yet to be established, antibody testing for other respiratory illnesses (SARS, flu) provides insight into immunity to future diseases.

   Quest has performed and reported results of approximately 975,000 COVID-19 antibody tests. We are now able to perform approximately 200,000 antibody tests a day, or 1.4 million a week. Our test capacity outpaces demand and we have not experienced a test backlog to date. We perform antibody testing in more than 20 Quest Diagnostics labs around the country.

  We are reporting antibody test results within 1–2 days from specimen collection, depending on demand. Quest continues to scale up testing capacity on the serology platform by expanding testing across its network of laboratories and adding other testing platforms.

  Test Code 39504 SARS-CoV-2 Serology (COVID-19) Antibody (IgG), Immunoassay: The SARS-CoV-2 (COVID-19) antibodies, Immunoassay test is a qualitative immunoglobulin (IgG) test to detect antibodies to the SARS-CoV-2 virus in the blood. The test code 39504 includes testing for the IgG antibody only.

   Quest will also be collecting serology specimens by appointment at Patient Service Centers (PSCs) across the country, outside of the first hour of the day designated for the Peace of Mind of those patients at greatest risk for COVID-19. Appointments can be scheduled online or by calling 1.866.MYQUEST (1.866.697.8378).

   The test is intended for use as an aid in identifying individuals with an adaptive immune response to SARS-CoV-2, indicating recent or prior infection. Results are for the detection of SARS-CoV-2 antibodies. IgG antibodies to SARS-CoV-2 are generally detectable in blood several days after initial infection, although the duration of time antibodies are present post-infection is not well characterized. At this time, it is unknown for how long antibodies persist following infection and if the presence of antibodies confers protective immunity. Individuals may have detectable virus present for several weeks following seroconversion. Negative results do not preclude acute SARS-CoV-2 infection. If acute infection is suspected, molecular testing for SARS-CoV-2 is necessary. The test should not be used to diagnose acute SARS-CoV-2 infection. False positive results for the test may occur due to cross-reactivity from pre-existing antibodies or other possible causes.

  • 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 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.