What is COVID Antibody Testing, Anyway?

A COVID-19 serology (or antibody) test is a blood test that shows if you have recently been infected with SARS-CoV-2 (the virus that causes COVID-19) – even if you never had any symptoms. Currently offered by LifeLabs, the test does not diagnose active COVID-19 infection, but rather suggests whether you have previously been infected by detecting antibodies in your blood that are reactive to SARS-CoV-2 viral proteins.

Who is antibody testing for?

Getting a COVID-19 antibody test can be an effective tool to help you make better decisions about your health. Antibody testing may be helpful if you:

• Were previously exposed to or infected with SARS-CoV-2, even if you were asymptomatic,
• Have signs or symptoms of COVID-19, but have repeatedly tested negative for SARS-CoV-2 by the molecular test, or
• Display long-term symptoms of COVID-19 but have never been diagnosed by a molecular test.

Antibody response varies from person-to-person and can take up to 3-4 weeks after you’ve first experienced symptoms or after you’ve first been exposed to be reliably detectable by antibody tests.

What do my results mean?

A ‘Reactive’ (positive) SARS-CoV-2 antibody result means you have antibodies that are reactive to the SARS-CoV-2 virus, which typically means that you very likely had a COVID-19 infection in the recent past. It is important to note that having a positive result does NOT infer immunity or protection from re-infection. Physical distancing and proper personal protective equipment are still required.

A Non-reactive (negative) COVID-19 antibody test result means that antibodies to SARS-CoV-2 were not detected in your blood sample. This could occur if:

• You have not been infected with SARS-CoV-2, or
• You were infected with SARS-CoV-2 in the past but your antibody levels were too low for the test to detect, or
• You have been infected with SARS-CoV-2, but there has not been enough time for antibodies to develop.

Please note: The COVID-19 antibody test currently offered by LifeLabs cannot be used to detect anti-viral antibodies following vaccination. The test detects antibodies against the nucleocapsid (N) protein of the SARS-CoV-2 virus, while vaccines illicit antibodies to the spike (S) protein of the virus particle. Detection of antibodies in response to vaccination requires a test directed towards the SARS-CoV-2 viral spike protein.

How to order:

The antibody test can be ordered online at LifeLabs.com for only $75. Alternatively, if your physician signs an OHIP requisition, it must contain “SARS-CoV-2 Total Antibody” in the Other Tests section and you will pay the $75 fee during your LifeLabs visit. You can also access our online virtual care partners on the LifeLabs’ my results™ portal. Be sure to follow up with your physician afterwards to discuss your results

To learn more about whether antibody testing is right for you, visit LifeLabs.com/covid19

Each year LifeLabs performs over 112 million laboratory tests to help diagnose, treat, monitor and prevent diseases for millions of Canadians.