Covid-19 Antibody Testing (SARS-COV-2)
Our partner laboratories currently offer Covid-19 antibody testing. There are two antibody tests offered by the lab completed together:
- Nucleocapsid Qualitative Test
- Spike Qualitative Test
The Total Nucleocapsid antibody test can determine if an individual has had exposure to covid protein through vaccination or by acquiring the disease. The Total Spike Qualitative test does not differentiate between exposure through vaccination or through infection.
The current guidance is to not currently test for covid 19 antibodies. There are a number of variables that can affect whether the antibody test produces a reliable result, including the test assay used by the laboratory.
- Testing for anti-bodies less than 3 weeks after exposure or symptom onset.
- Antibody levels can wane long after an individual has had Covid-19 or vaccination against Covid-19, even if they have been vaccinated or have had Covid-19.
- You are experiencing symptoms of an active infection.
- To guide a decision to get vaccinated.
- To determine the need to quarantine after exposure to Covid-19
- There is a risk of a false-positive result with the test assay used by the laboratory (i.e. individuals with rheumatoid arthritis and heterophile antibodies AKA mononucleosis). This means the test may show you have had exposure to the virus, when in fact you have not.
- The antibody test cannot tell whether you are actively shedding the virus.
- A positive result does not mean you have protection or immunity from re-infection.
A general rule of thumb is to wait 3-4 weeks after symptom onset or exposure, and 3 weeks after your last vaccine.
The following table provides the interpretation of the test results. If you have questions about covid-19, you can book an appointment with one of our physicians to discuss your results.
Vaccination Status | Nucleocapsid Antibody | Spike Qualitative Antibody | Interpretation |
Vaccinated | + | + | Vaccinated and previously infected |
Vaccinated | - | - | Vaccinated and not previously infected |
Unvaccinated | + | + | Unvaccinated and previously infected |
Unvaccinated | - | - | Unvaccinated and not previously infected |
Last modified 1mo ago