With the large number of COVID-19 tests available to the public, it’s easy to get lost in the different testing options. Here’s a quick summary of the different COVID-19 tests and which ones may be right for you.

COVID-19 / PCR diagnostic tests

A COVID-19 diagnostic test determines if you are currently infected with COVID-19. Also known as the COVID-19 PCR test, this test confirms whether you are actively infected with the virus. The term polymerase chain reaction (PCR) refers to the laboratory technique used.

What happens during this test

There are several ways to perform a COVID-19 PCR test. The test method used will depend on the site / location where you are having the test performed.

  • Nasopharyngeal swab – A long nasal swab is inserted into your nostril and a small sample is taken from the back of your nose.
  • Oropharyngeal swab – A long swab is inserted at the back of the throat.
  • Saliva test – You can spit into a tube to produce a saliva sample.

When to get tested

A COVID-19 diagnostic test is recommended if you have symptoms or have had close contact with someone who tests positive for the COVID-19 virus or who is suspected of having the virus. Houston COVID-19 PCR test available at both LifeSavers ER sites.

What do the test results mean

A positive COVID-19 diagnostic test means you have an active COVID-19 infection. As per CDC guidelines, you must self-quarantine for 10 days.

A negative COVID-19 test means that at that time you have tested negative for the virus. If you are showing symptoms of COVID-19 but tested negative, it is possible that you were tested too early or received a false negative result. In this case, continue to quarantine yourself and talk to your doctor about the possibility of getting tested again in a few days.

How accurate is the test

PCR tests are very accurate when performed correctly by a healthcare professional.

COVID-19 antigen testing

The COVID-19 antigen test detects certain fragments of proteins (antigens) of the COVID virus. Antigen test reveals whether a person is currently infected with COVID-19. These tests are useful for identifying people whose infection with the COVID-19 virus is at or near their highest. Antigen tests are cheaper and generally faster than COVID-19 PCR tests. The downside is that they can be less accurate than COVID-19 PCR tests.

What happens during this test

A nasal or throat swab is used to obtain a sample.

When to get tested

Antigen tests can be used in place of COVID-19 PCR diagnostic tests. However, they are less accurate than PCR tests.

The Centers for Disease Control and Prevention (CDC) has advised people who show symptoms of COVID-19 but test negative with this rapid antigen test to obtain a COVID-19 PCR test to confirm the results. Houston COVID-19 antigen testing available at both LifeSavers ER locations.

What do the test results mean

A positive antigen test is confirmation of an active infection with COVID-19. However, these tests have a significantly higher false negative rate (the test returns negative for the virus but the individual is in fact infected with the virus). A COVID-19 PCR diagnostic test is the most accurate way to confirm whether you are actively infected with COVID-19 or not.

How accurate is this test

There is an increased risk of false negative results, which means it is possible to be infected with the virus but have a negative result. Confirmation of true infection status can be obtained with a COVID-19 PCR test.

COVID-19 antibody test

This test determines if you have ever had COVID-19 and if you now have antibodies to the virus. The antibody test is usually done after complete recovery from COVID-19.

An antibody test is NOT a substitute for a COVID-19 PCR diagnostic test and cannot be used to diagnose a person with an active infection.

What happens during this test

A healthcare professional takes a sample of blood, usually with a finger prick or by drawing blood from a vein in the arm. The blood sample is sent to the laboratory for processing.

When to get tested

Antibody tests are not recommended until at least 14 days after the onset of symptoms. If done too early, the results may give a false negative result. Antibody test results should NOT be used to diagnose a person with an active infection. Houston COVID-19 antibody tests available at both LifeSavers ER sites.

What do the test results mean

A positive COVID-19 antibody test means that you have likely been infected with COVID-19 at some point in the past. It can also mean that you have some immunity. However, there is a lack of scientific evidence on the duration of immunity to COVID-19 and the effectiveness of that immunity. Therefore, continue to follow all precautions regarding mask wearing and social distancing


Understanding Antibody and PCR Testing