The many COVID-19 tests can be broadly grouped into diagnostic (viral) tests and antibody (serology) tests.
Diagnostic (viral) tests can indicate whether a person has an active COVID-19 infection and needs to take steps to quarantine or isolate. Molecular and antigen tests are two types of diagnostic (viral) tests that can detect active COVID-19 infection. Typically, diagnostic tests are performed on samples collected with a nasal or throat swab or saliva collected in a tube.
Antibody (serology) tests detect antibodies in the immune system produced in response to COVID-19 infection. Antibody tests are not used to diagnose an active COVID-19 infection. Antibodies typically take several days or weeks to develop after a COVID-19 infection and may remain in the blood for several weeks or more after recovery. Blood samples are typically used for antibody tests.
