What is the difference between the types of tests available for COVID-19?
Diagnostic vs. Antibody Tests
There are two different types of tests – diagnostic tests and antibody tests. A diagnostic test can show if you have an active coronavirus infection and should take steps to quarantine or isolate yourself from others.
Currently there are two types of diagnostic tests – molecular (RT-PCR) tests that detect the virus's genetic material, and antigen tests that detect specific proteins on the surface of the virus. Samples are typically collected with a nasal or throat swab, or saliva collected by spitting into a tube.
An antibody test looks for antibodies that are made by the immune system in response to a threat, such as a specific virus. Antibodies can help fight infections. Antibodies can take several days or weeks to develop after you have an infection and may stay in your blood for several weeks after recovery.Testing for CoVID-19 falls into two categories: diagnostic tests and antibody tests.
Some of this content first appeared at https://www.fda.gov/emergency-preparedness-and-response/coronavirus-disease-2019-covid-19/covid-19-frequently-asked-questions#:~:text=There%20are%20two%20different%20types,several%20weeks%20after%20recovery and at https://www.fda.gov/consumers/consumer-updates/coronavirus-testing-basics.