Antigen swab and PCR are currently widely used as a screening measure for COVID-19. Both types of tests are considered to be able to diagnose someone infected with the corona virus or not. But, there are some difference such as the method and also the level of accuracy.
PCR or polymerase chain reaction is a method of examining the Covid-19 virus by detecting viral DNA. But in fact, at this time PCR can not be the determinant of a person has recovered from Covid-19 or not. Self-isolation for 10-14 days and free of symptoms is the standard.