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You shouldn’t always trust a negative COVID test, doctors say

Here’s why you should trust your symptoms and a doctor’s advice over a test result

SHARE You shouldn’t always trust a negative COVID test, doctors say
An illustration of the omicron COVID-19 variant.

Illustration by Alex Cochran, Deseret News

Have you ever experienced COVID-19 symptoms, but after several tests, the results keep coming back negative? This isn’t uncommon.

False negatives: Doctors are finding that a negative COVID-19 test can’t always be trusted.

  • “With any variant, someone could show up with a negative test for the first two days of symptoms, potentially, and then turn positive maybe on the third or fourth day,” said Dr. Emily Volk, president of the College of American Pathologists, according to the American Medical Association.
  • Volk’s advice is to wait at least five days after exposure to do a rapid test. If you have recently been in a large group of people, and are beginning to feel unwell, she suggests a PCR test for more accurate results.
  • McGill University in Canada states that rapid tests are more likely to miss the omicron variant, compared with any other variant.

Why do false negatives happen? A researcher at Rutgers University says that “after the first week of infection, there is a decline in virus shedding in the respiratory tract, where tests can become falsely negative.”

  • In other words, the Centers for Disease Control and Prevention say that a negative COVID-19 test doesn’t always mean the virus isn’t there — it just means the test hasn’t detected it.
  • Rutgers also says to trust a doctor’s advice over the results of a rapid test.

What about false positives? McGill University says that these are very rare, only happening 0.05% of the time.