Rapid antigen nasal swab test: why don’t most people with COVID need to test for another 30 days One study suggests the virus takes an average of 36 days to clear from the body after symptoms first appear.

Throat swab is the most important sampling method for diagnosing COVID-19 infection. Correct sampling is the key to improve the accuracy of pharyngeal swab nucleic acid detection.Pharyngeal division includes nasopharynx, oropharynx and laryngopharynx.