How does the PCR test work?
The test consists of inserting a soft cotton swab (swab) into each nostril up to the nasopharynx for a few minutes. This process is unpleasant but not painful. The sample is then analyzed in the laboratory using a method called “polymerase chain reaction” (PCR). This technique makes it possible to detect the RNA of the virus, its genome, which characterizes it in a way. The best time to detect SARS-CoV-2 RNA is 1-7 days after symptom onset. Before or after this period, the PCR test would no longer be optimal. Learn more