Rapid antigen tests are the fastest way of diagnosing SARS-CoV-2, the virus that causes COVID-19. You can get the results of your rapid test within 15 minutes, but these tests are not shown to be as accurate as the PCR tests that were the only option in the early stages of the pandemic. This is because rapid tests require more of the virus to be present in your body in order to diagnose you with the virus, meaning there is a higher chance of receiving a false negative than there is with a PCR test. If you are experiencing symptoms of COVID-19 and your rapid test continues to produce negative results, it is still advised to isolate until you no longer have symptoms.