An antigen test diagnoses active coronavirus infection from a nasal or throat swab.

Antigen test results are ready in one hour or less.

Antigen tests detect specific proteins on the surface of the virus, while molecular tests, such as RT-PCR tests, detect the virus’ genetic material.

Antibody tests (i.e. finger stick, ELISA, ECLIA) should not be used to diagnose an active coronavirus infection because antibodies can take several days or weeks to develop after you have an infection.

Source: US FDA

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