SARS-CoV-2 can be diagnosed using a PCR RNA test that detects viral genetic material in a nasal swab sample. Saliva tests are also available. Viral antigen tests that detect fragments of viral proteins are simpler to perform but less accurate. Testing positive indicates current active infection.

Another type of test detects antibodies to the coronavirus in the blood, which reveal whether someone was infected in the past. These antibodies offer protection against future infection, but it is not yet known how long this immunity will last.

If you think you may have been exposed to the coronavirus, contact a health care provider if you develop a fever, cough, difficulty breathing or other symptoms. Before you go to a clinic or hospital, call ahead so the staff can give you instructions and take appropriate precautions.

Last Reviewed: April 29, 2021