Types of COVID-19 tests and how they work
COVID-19 tests can determine if you are currently infected with SARS-CoV-2, the virus responsible for COVID-19. These tests typically use samples from your nose or mouth and fall into two main categories: molecular or PCR tests, and antigen tests. Some COVID tests can be self-administered at home, eliminating the need to visit a healthcare facility. Most at-home COVID tests are antigen tests. When testing yourself at home, it’s important to follow the instructions provided with the covid test kit to ensure an accurate result. By understanding the differences and appropriate use of each test type, you can make informed decisions about coronavirus testing based on your specific needs and circumstances.
Polymerase chain reaction (PCR) tests detect the virus’s genetic material or ribonucleic acid (RNA). These tests are highly sensitive and more reliable than antigen tests, especially for detecting the virus in people who suspect they have COVID but show no symptoms. Samples for PCR tests are usually collected by healthcare providers and sent to a lab for analysis, with results typically available within three days.
Antigen tests, commonly referred to as rapid tests, detect specific proteins from the virus. These tests provide results quickly, usually within 15 to 30 minutes. While rapid tests are reliable for confirming positive cases, they are less sensitive than PCR tests. They may not detect the virus in asymptomatic patients or people who were recently infected. The Food and Drug Administration (FDA) recommends repeat testing if an antigen test is negative. A PCR test can confirm the results of an antigen test if needed.