The Difference between PCR, Antigen, and Antibody Tests

Table header 0PCR TestAntigen Test
ConceptSARS-CoV-2 has genetic material in the form of RNA. Presence of COVID-19 specific viral RNA from patient samples indicate that the patient is SARS-CoV-2 infected.
Antigens are present on the surface of the virus. Presence of COVID-19-specific antigen in patient samples indicate that the patient is SARS-CoV-2 infected.
Testing PrinciplePCR tests amplify and detect targeted region of SARS-CoV-2 genetic material.Antigen tests detect SARS-CoV-2 antigen in patient samples.
Sample TypeNasal, nasopharyngeal swab, oropharyngeal swab, deep throat salivaNasal, nasopharyngeal swab, oropharyngeal swab
BiomarkerSARS-CoV-2 virusSARS-CoV-2 antigen
Suitable period for useFrom onset of infectionFrom 2 days after infection

Operation

Time
4-6 hoursAround 20 minutes
Operation RequirementsProfessional medical operator and lab equipmentNo professional operator or equipment required