The following methods are used in the diagnosis of COVID-19
The COVID-19 PCR test detects the presence of viral RNA in the test sample and is used to diagnose the actual current viral infection. This test is the most sensitive method currently in use, but it takes longer than other tests and is expensive.
The COVID-19 antigen test (also known as “rapid test”) is an immunological test detecting viral protein(s) and is used to diagnose the actual current viral infection. The test is less sensitive than the PCR test and often provides a false-negative result when the viral load is low. The advantages of this test are its speed and low price.
COVID-19 Antibody/Serology test detects virus-specific antibodies in the blood and is used to assess prior COVID-19 infection or the efficiency of vaccination. This test is rapid and inexpensive. However, it cannot be used to diagnose current actual COVID-19 infection as antibodies appear within 1-3 weeks after infection or vaccination.