COVID-19 IgG antibody testing


BFAC team during COVID-19 war. Taken 4/23/2020 From left to right: Erin, Barbara, Cat, Dr. Leung, Robert, Sarah.


What does the test tell you?

According to the U.S. Food and Drug Administration, COVID-19 antibody testing may indicate that "the person has been exposed to the virus and developed antibodies against it, which may mean that person has at least some immunity to the coronavirus." We are using Quest Diagnostics platform, and you can find more information from their website. Product insert can found here.

How can I schedule?

Call (617)804-6767.

How soon can I schedule the test?

Same day or next day, by appointment only.

How and where is the test being done?

The test requires a blood draw which is done in a private patient room located in our infusion center. Our infusion center is physically separated from our patient area. An experienced phlebotomist, specialized in both adult and pediatric blood draws, with full personal protective equipment (mask, gloves, gown and face shield) will draw your blood. Blood samples are then transferred and analyzed at Quest Diagnostics Laboratory.

When will I receive my test results?

Results are usually available in 1-2 days. Dr Leung will discuss the results with you over the phone once the results are back.

I am not currently a patient of Dr. Leung. Can I still get the testing done in his office?

YES. However, you will need to establish care with Dr. Leung (done on the same visit as the blood draw), so he can understand your medical history and interpret the result for you in the right context. The visit takes 15-20 minutes and can usually be done virtually prior to visit.

Does insurance cover the visit and COVID-19 antibody testing?

You will need to call your insurance company to confirm coverage. Below is the information patients often need:
  • Physician name: Dr. John Leung
  • Practice Name: Boston Food Allergy Center
  • Clinic address: 65 Harrison Ave, Suite 201, Boston, MA 02111
  • For patients in NEQCA network, use both NPI: 144-732-8711 and TIN: 81-07-64-208 to identify Dr. John Leung
  • For patients in Stewards network, use NPI = 102-356-1966
  • Name of the antibody test: “SARA-CoV-2-SEROLOGY (COVID-19) ANTIBODY (IgG), IMMUNOASSAY” and it is offered byQuest Diagnostics
  • For more insurance-related information, click here

Can you share some of the scientific facts of this antibody test?

  • This COVID-19 IgG test is designed to indicate recovery from recent infection.
  • COVID-19 IgG test isNOT designed to detect ongoing ACTIVE INFECTION.
  • There are no current guidelines/recommendations from any professional group pertaining the utility of this test.
  • Some studies have found that up to 15% of the people will not form detectable antibodies after infection.
  • A positive IgG test does not guarantee you cannot be re-infected again, as cases of re-infection have been reported.
  • Some data suggests that viral shedding may still occur in patients with positive IgG antibody.
  • Sensitivity of this test: 90% - 100% (assessed as the percent agreement of serology results on known COVID-19 PCR positive cases).
  • Specificity of this test: 99% - 100%. This was assessed by performing cross-reactivity studies utilizing serum samples positive for antibodies to other respiratory viruses, as well as panels of samples from pre-COVID times (2010, 2017, and 2019).
  • A false negative IgG result may occur if sample is drawn earlier than 10 days post onset of symptoms or due to immunosuppressant.
  • Sensitivity of SARS-CoV-2 IgG increases further around day 15 post onset of symptoms.
  • With such high specificity, false positive rates are minimal. (full Package Insert is also attached)
  • This test does not currently have an Emergency Use Authorization (EUA), just like many of the other antibody tests on the market currently. However, it does have an EUN (Emergency Use Notification) and is applying for EUA. See here for more information.

What is the advantage of doing it at Dr. Leung’s office?

  • Dr. Leung is a board certified immunologist who can interpret the antibody result for you within the appropriate context
  • Blood draw/appointment occurs in a private room that is disinfected after each use.
  • Our social distancing and disinfection protocols are consistent with, if not in most cases exceed, the standards recommended by CDC
  • Phlebotomist/personnel will be donned in full PPE equipment, including N-95 masks, face shield, and gown to minimize any risk of transmission at our site.
  • Click here to find out more about our strategies to keep you safe.