Polymerase chain reaction (PCR) and rapid (antigen) tests for COVID-19 both involve taking a swab. Results for a PCR test take longer, as it needs to go to a laboratory. It is more costly but tends to ...

A polymerase chain reaction (PCR) test detects genetic material from a pathogen or abnormal cell sample. Ways of collecting samples include a nasal swab, a saliva swab, or taking a sample of blood.

If you had COVID-19 symptoms in 2020, you probably would have masked up and braved a visit to a laboratory, doctor’s office, or clinic to get a polymerase chain reaction (PCR) test. A health care ...

Passengers arriving in the UK from another country must take a PCR test by day two after their arrival and must also isolate until the results, Boris Johnson has said. PCR tests must be ordered from a ...

COVID-19 tests are in greater demand than ever, and new data about the Omicron variant can make picking and using different types of tests confusing. Molecular tests for COVID-19, like the "RT-PCR" ...

Scientists consider polymerase chain reaction, or PCR, tests a highly reliable tool for diagnosing COVID-19. But social media posts are misrepresenting a recent Centers for Disease Control and ...