COVID-19 virus test
COVID 19 - Nasopharyngeal swab; SARS CoV-2 testTesting for the virus that causes COVID-19 involves taking a mucus sample from your upper respiratory tract. This test is used to diagnose COVID-19.
The COVID-19 virus test is not used to test your immunity to COVID-19. To test if you have antibodies against the SARS-CoV-2 virus, you need a COVID-19 antibody test.
COVID-19 antibody test
This blood test shows if you have antibodies against the virus that causes COVID-19. Antibodies are proteins produced by the body in response to ha...
Read Article Now Book Mark ArticleHow the Test is Performed
Testing is usually done in one of two ways. For a nasopharyngeal test, you will be asked to cough before the test begins and then tilt your head back slightly. A sterile, cotton-tipped swab is gently passed through a nostril and into the nasopharynx. This is the uppermost part of the throat, behind the nose. The swab is left in place for several seconds, rotated, and removed. This same procedure may be done on your other nostril.
For an anterior nasal test, the swab will be inserted into your nostril no more than 3/4 of an inch (2 centimeters). The swab will be rotated 4 times while pressing against the inside of your nostril. The same swab will be used to collect samples from both nostrils.
Tests may be done by a health care provider at an office, drive-through, or walk-up location. Check with your local health department to find out where testing is available in your area.
At-home testing kits are also available that collect a sample using either a nasal swab or a sample of saliva. The sample is then either sent to a lab for testing, or with some kits, you can get results at home. Contact your provider to see if home collection and testing is appropriate for you.
At-home testing
Self-testing for COVID-19 can be done using an over-the-counter (OTC) rapid antigen test to find out if you have COVID-19 infection. An OTC test for...
Read Article Now Book Mark ArticleThere are two types of virus tests available that can diagnose COVID-19:
- Polymerase chain reaction (PCR) tests (also called Nucleic Acid Amplification Tests) detect the genetic material of the virus that causes COVID-19. The samples are usually sent to a laboratory for testing, and results are usually available in 1 to 3 days. There are also rapid PCR diagnostic tests that are run on specialized equipment on-site, for which the results are available in several minutes.
- Antigen tests detect specific proteins on the virus that causes COVID-19. Antigen tests are rapid diagnostic tests, which means the samples are tested on-site, and results are available in several minutes.
- Rapid diagnostic tests of any kind are less accurate than the regular PCR test. If you get a negative result on a rapid test, but have symptoms of COVID-19, your provider may do a non-rapid PCR test.
If you have a cough that produces phlegm, the provider may also collect a sputum sample. Sometimes, secretions from your lower respiratory tract can also be used to test for the virus that causes COVID-19.
How to Prepare for the Test
No special preparation is needed.
How the Test will Feel
Depending on the type of test, you may have slight or moderate discomfort, your eyes may water, and you may gag.
Why the Test is Performed
The test identifies the SARS-CoV-2 virus (severe acute respiratory syndrome coronavirus 2), which causes COVID-19.
COVID-19
Coronavirus disease 2019 (COVID-19) is mainly a respiratory illness that causes fever, coughing, and shortness of breath, but many other symptoms can...
Normal Results
The test is considered normal when it is negative. A negative test means that at the time you were tested, you probably didn't have the virus that causes COVID-19 in your respiratory tract. But you can test negative if you were tested too early after infection for COVID-19 to be detected. And you can have a positive test later if you are exposed to the virus after you were tested. Also, rapid diagnostic tests of any kind are less accurate than the regular PCR test.
For this reason, if you have symptoms of COVID-19 or you are at risk for contracting COVID-19 and your test result was negative, your provider may recommend being retested at a later time.
What Abnormal Results Mean
A positive test means that you are infected with SARS-CoV-2. You may or may not have symptoms of COVID-19, the illness caused by the virus. Whether you have symptoms or not, you can still spread the illness to others. You should isolate yourself in your home and learn how to protect others from developing COVID-19. You should do this immediately while waiting for more information or guidance. You should stay at home and away from others until you meet the guidelines for ending home isolation.
Symptoms of COVID-19
COVID-19 is a highly infectious respiratory illness caused by a new, or novel, virus called SARS-CoV-2. COVID-19 is spreading quickly throughout the...
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Ending home isolation
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Read Article Now Book Mark ArticleReferences
Centers for Disease Control and Prevention website. COVID-19: Self-testing at home or anywhere. www.cdc.gov/coronavirus/2019-ncov/testing/self-testing.html. Updated March 9, 2022. Accessed March 15, 2022.
Centers for Disease Control and Prevention website. COVID-19: Interim guidelines for collecting, handling, and testing clinical specimens for COVID-19. www.cdc.gov/coronavirus/2019-ncov/lab/guidelines-clinical-specimens.html. Updated October 25, 2021. Accessed March 15, 2022.
Centers for Disease Control and Prevention website. COVID-19: Overview of testing for SARS-CoV-2 (COVID-19). www.cdc.gov/coronavirus/2019-ncov/hcp/testing-overview.html. Updated February 11 2022. Accessed March 15, 2022.
Centers for Disease Control and Prevention website. COVID-19: Test for current infection. www.cdc.gov/coronavirus/2019-ncov/testing/diagnostic-testing.html. Updated February 22, 2022. Accessed March 15, 2022.
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COVID-19 - illustration
Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, a respiratory illness that ranges from mild symptoms to pneumonia or even death. Symptoms occur within 2 to 14 days from exposure to the virus and may include fever, cough, shortness of breath, chills, muscle pain, headache, sore throat, and new loss of sense of taste or smell. COVID-19 may be more severe in people who are older or who have chronic health conditions, such as heart disease or diabetes.
COVID-19
illustration
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Respiratory system - illustration
Air is breathed in through the nasal passageways, travels through the trachea and bronchi to the lungs.
Respiratory system
illustration
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Upper respiratory tract - illustration
The major passages and structures of the upper respiratory tract include the nose or nostrils, nasal cavity, mouth, throat (pharynx), and voice box (larynx). The respiratory system is lined with a mucous membrane that secretes mucus. The mucus traps smaller particles like pollen or smoke. Hairlike structures called cilia line the mucous membrane and move the particles trapped in the mucus out of the nose. Inhaled air is moistened, warmed, and cleansed by the tissue that lines the nasal cavity.
Upper respiratory tract
illustration
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COVID-19 - illustration
Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, a respiratory illness that ranges from mild symptoms to pneumonia or even death. Symptoms occur within 2 to 14 days from exposure to the virus and may include fever, cough, shortness of breath, chills, muscle pain, headache, sore throat, and new loss of sense of taste or smell. COVID-19 may be more severe in people who are older or who have chronic health conditions, such as heart disease or diabetes.
COVID-19
illustration
-
Respiratory system - illustration
Air is breathed in through the nasal passageways, travels through the trachea and bronchi to the lungs.
Respiratory system
illustration
-
Upper respiratory tract - illustration
The major passages and structures of the upper respiratory tract include the nose or nostrils, nasal cavity, mouth, throat (pharynx), and voice box (larynx). The respiratory system is lined with a mucous membrane that secretes mucus. The mucus traps smaller particles like pollen or smoke. Hairlike structures called cilia line the mucous membrane and move the particles trapped in the mucus out of the nose. Inhaled air is moistened, warmed, and cleansed by the tissue that lines the nasal cavity.
Upper respiratory tract
illustration
Review Date: 3/15/2022
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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