TESTING AND IMMUNITY
Many people who have had COVID-19 are eager to know whether they can get the disease again, or if they are immune. Previous studies conducted in the `70s and `80s concluded that reinfections are possible with coronaviruses. However, of the millions of patients who have recovered from COVID-19, which is caused by a coronavirus, only a handful have been confirmed as having gotten the disease again. Based on the reported recurrence rate from the early stages of ongoing research, the chances of becoming reinfected appear to be very small.
The human body produces proteins called antibodies to fight infections. An antibody test is a blood test that finds these proteins, and there is such a test that can detect COVID-19 antibodies. This test is used to determine whether patients have had COVID-19 but is typically not used to diagnose the disease. If a test finds that you have antibodies to COVID-19 in your body, you are likely immune from getting the disease again for a certain period. In fact, that is how vaccines work.
If you have tested positive for COVID-19 antibodies, you can help speed the development of a COVID-19 vaccine by donating blood for a vaccine research clinical study.
People who have recovered from COVID-19 and are not showing new symptoms are advised not to get a test for the disease in the 3 months immediately after their first positive test because they will continue to carry low levels of the virus that can trigger a positive result, even if they no longer have COVID-19. Those who experience new symptoms should be retested for the disease right away.