Source: US Gov Centers for Disease Control and Prevention
Types of Tests
Viral tests look for a current infection with SARS-CoV-2, the virus that causes COVID-19, by testing specimens from your nose or mouth.
There are two main types of viral tests:
- Polymerase chain reaction (PCR) tests
- Antigen tests
PCR Tests
PCR tests are the “gold standard” for COVID-19 tests. They are a type of nucleic acid amplification test (NAAT), which are more likely to detect the virus than antigen tests. Your sample will usually be taken by a healthcare provider and transported to a laboratory for testing. It may take up to 3 days to receive results.
Antigen Tests
Antigen tests* are rapid tests that usually produce results in 15-30 minutes. Positive results are accurate and reliable. However, in general, antigen tests are less likely to detect the virus than PCR tests, especially when symptoms are not present. Therefore, a single negative antigen test cannot rule out infection. To be confident you do not have COVID-19, FDA recommends 2 negative antigen tests for individuals with symptoms or 3 antigen tests for those without symptoms, performed 48 hours apart. A single PCR test can be used to confirm an antigen test result.
*Self-tests, or at-home tests, are antigen tests that can be taken anywhere without having to go to a specific testing site. Read self-test package inserts thoroughly and follow the instructions closely when performing the test.