Positive test results
If you have a positive test result (antibodies are detected), you may have been infected with COVID-19 at some point in the past. There is still a chance that the antibodies indicate past infection due to other coronaviruses. These other coronaviruses cause the common cold. There is also a small chance that a positive result is incorrect (false positive).
- If IgM early-stage antibodies (with or without IgG) are detected, it indicates that an infection has occurred within the last few weeks. It also suggests that you could still be infectious. It is strongly recommended to have a PCR test to confirm.
- If IgG antibodies, without IgM, are detected, it suggests that the infection has happened weeks to months in the past. It also may indicate that you may no longer be infectious. IgG indicates that you may have some immunity to the virus, though you may not.
Negative test results
A negative test result means that the antibodies to COVID-19 were not detected in your sample. However, it is possible for this test to give a negative result that is incorrect (false negative) in some people.
A negative result may occur if you are tested early in your illness and your body hasn’t had time to produce antibodies to the infection. This means that you could possibly still have COVID-19 even though the test is negative.