There are multiple types of tests for COVID-19 that can be used to detect active infection or to detect past infection or immunization.
COVID-19 testing can be used for diagnosis, screening, or monitoring:
- Diagnosis is testing for COVID-19 in people who have shown symptoms of the disease.
- Screening is testing in people who have not shown symptoms. For COVID-19, screening is often done for people who have been in close contact with someone who has tested positive.
- Monitoring is a method of follow-up to determine if a person who was previously diagnosed with COVID-19 continues to test positive.
Another role of testing is looking for indications of a prior infection with SARS-CoV-2 or prior immunization. This is known as serological or antibody testing.