As cases skyrocket, you should know the different types of tests out there. Which is confusing.
There are 2 types of diagnostic tests. Diagnostic tests tell you if you CURRENTLY have COVID19. If these come back positive, you NEED to quarantine or isolate yourself from others.
1. Molecular test. (Also called RT-PCR, viral test, molecular test, NAAT, LAMP test). This detects the genetic material of a virus. This test can be a nasopharyngeal (part of the throat behind the nose), nasal or throat swab or saliva test. You should get results the same day in some locations or up to a week at other locations. It is highly accurate (almost 100% in detecting infected people) and highly sensitive (so it will detect minuscule amounts of virus).
2. Antigen test. This detects specific parts of the virus (called proteins). It is a nasal or nasopharyngeal swab. You will get results very quickly (within 15 minutes). Positive results are usually highly accurate, but false positive can happen. Antigen tests are more likely to miss an active COVID19 infection because you need more of the virus particles present for detection (compared to PCRs). Negative results may need to be confirmed with a PCR test if you have symptoms (check with your doctor).
The other type of test is an antibody test. (also known as serological test, serology, blood test). This test detects whether you were ever infected with COVID19 in the PAST. This will not tell you if you are currently infected. This is a finger stick or blood draw. You should know results 1-3 days after. Sometimes you need a second antibody test for accurate results. It sometimes takes weeks after infection to develop enough antibodies to be detected in a test. You do not need to quarantine if this test is positive.
Check out the figure for the most ideal time for each test.
The best way to get a COVID19 test is to contact your doctor. Your state and local health departments also typically have testing information on their website.
Data Sources: Nature article: https://www.nature.com/articles/d41586-020-02661-2… ; https://www.fda.gov/…/coronavirus-disease-2019-testing…