Viral Test for COVID-19

Viral Test for COVID-19

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Viral Test for COVID-19


A COVID-19 viral test is a way to find out if you have COVID-19. The test looks for the genetic material of the virus in cells from your breathing passages or lungs (respiratory system). This may also be called a nucleic acid or antigen test.

This test is used to diagnose a current infection with SARS-CoV-2, the virus that causes COVID-19. Knowing that you have the virus means that you can take steps to protect others from getting infected. This can help limit the spread of the virus.

Knowing who has COVID-19 is also important for experts who track the virus. It can help them learn more about how the virus spreads.

The test is most often done on a sample from your nose, throat, or lungs. It's sometimes done on a sample of saliva. One way a sample is collected is by putting a long swab into the back of your nose.

The result is either positive or negative.

A positive result means that the genetic material of the virus was found in your sample. You have COVID-19 now.

A negative result means that the genetic material was not found. This may mean that you don't have COVID-19. But it's possible to get a "false-negative" result. This means that the test shows that you don't have COVID-19 when in fact you do. This may happen because you were tested too soon after you were infected, before the virus started to spread in your nose and throat. Or it could happen because the swab missed the infection.

Related Information


Current as of: September 15, 2020

Author: Healthwise Staff

Medical Review:

Heather Quinn MD - Family Medicine

Lesley Ryan MD - Family Medicine