This is still a hot topic and the center of many social media debates as to where to actually get testing, what test you should ask for, and the accuracy of the test.
While many people have their opinions, it’s always best to look at the evidence and science first prior to making a decision yourself.
Keep reading to take a deeper dive into the different types of testing currently available for COVID-19, today, and which tests give specific infection information and data.
What Types of Testing Are Available For COVID-19?
There are two main categories of tests for assessing the presence or history of COVID-19:
Diagnostic Testing: To test whether you actually have the virus
Antibody Testing: To test whether you could have come in contact with the virus or have been infected in the past from the virus.
There has been a lot of news surrounding the use of antibody tests for COVID-19 as well as confusion about what the tests do.
Most people want to know which test they should ask for upon arriving at the clinic (with symptoms or not) and what the accuracy of the testing actually is.
In the most basic terms, antibody tests are used to determine if you have had a past COVID-19 infection, while PCR (or molecular based) tests are used to determine if you are currently infected.
There are several variations for each of these types of testing that we will dive into a bit further below.
1. Diagnostic Testing
There are a few different types of viral diagnostic testing available to the public currently.
Molecular PCR Testing
Molecular testing informs patients, physicians, or researchers of the presence of the pathogen, either by identifying its genetic material or identifying unique markers of the pathogen itself.
The test uses the exact viral ribonucleic acid (RNA) for SARS-CoV-2 (COVID-19) which remains in the body only while the virus is still replicating.
This type of testing usually requires samples from the patient that are likely to contain virus, such as nasopharyngeal swabs or sputum samples.
For diseases specific to the respiratory tract, such as COVID-19, nasopharyngeal swabs have been considered to be the most reliable, as they sample an area of the respiratory tract where the virus appears to first infect an individual.
For more in-depth knowledge around how molecular testing works, click HERE to learn and see many of the pro’s and con’s of different methods.
Antigen tests are another type of diagnostic test (to test if you have the active virus).
While antigen tests are newer to the market and can provide faster results, antigen tests have a higher chance of missing an active infection.
For example, if an antigen test shows a negative result (indicating that you do not have an active coronavirus infection) your health care provider may order a molecular test to confirm the result.
This is similar to how a pregnancy test works. If you see the positive result on the at home test, usually follow up blood work is warranted to confirm the results.
What is the main difference between Antigen testing and PCR testing for active infection of COVID-19?
The main difference that most consumers are worried about is ease of testing and accuracy.
While PCR tests can be incredibly accurate, obtaining the samples and analyzing the results can take time.
On the flip side, one of the main advantages of an antigen test is the speed of the test, which can provide results in minutes.
But (and this is the most important factor), antigen tests may not detect all active infections, as they do not work the same way as a PCR test.
Even though antigen tests are very specific for the SARS-COV-2 virus, they are not as sensitive as molecular PCR tests.
2. Antibody Tests
Antibody testing is not supposed to be used to "diagnose" an active infection from the virus, but can be extremely useful to see if you have been in contact with or have been infected from the virus in the past.
How Do Antibody Tests Work?
Whenever the immune system is confronted with a disease-causing organism like a virus, it produces defensive proteins called antibodies.
These antibodies are then stored for future use in the case that the organism comes back in contact with that exact virus.
The antibodies are matched specifically to that organism so that they can prevent a future infection down the road and are the main mechanism behind how vaccines work for specific diseases.
COVID-19 antibody tests are looking for the antibodies made in response to exposure to the SARS-CoV-2 virus.
There are two main types of antibodies, which are also called immunoglobulin (Ig), that the body can produce in response to a COVID-19 infection:
- Immunoglobulin M (IgM): The first antibody the immune system produces when confronted with a virus or other disease-causing pathogens.
It accounts for roughly 10% of all antibodies that the body produces and usually comes before the IgG antibodies within 5 days - several weeks after initial infection.
- Immunoglobulin G (IgG): These take longer to produce than IgM, but they are the predominant antibody found in blood and other body fluids.
These immunoglobulins play a key role in creating "memory" cells (B lymphocytes) that remain on guard after the infection has cleared, ready to attack in the event the invader returns.
Antibody tests may provide quick results, but should not be used to diagnose an active infection. That is what the diagnostic/molecular based testing is for.
Antibody tests only detect antibodies the immune system develops in response to the virus, not the virus itself.
The key to remember is that it can take days to several weeks to develop enough antibodies to be detected on a test.
There are two main tests available for testing for COVID-19 antibodies:
- Finger Prick Testing
- Serum/Venous Blood Draw Testing
Why blood draw over quick finger prick for antibody testing?
Most people would prefer to pay less money and have quicker results for their testing.
And who could blame them?
But the issue is that per the research and current results, serum testing is much more reliable and accurate when it comes to testing for antibodies.
Similar to the at-home pregnancy test analogy above, drawing blood to test for antibodies requires a full sample to be taken from the patient, then the sample if spun down and placed on specific lab instrumentation in order to detect antibodies.
Just like the PCR testing is more accurate than the antigen testing for the actual viral infection, drawing a sample of blood is much more accurate than simply using a finger prick to detect antibodies for COVID-19.
Why To Measure Your Own Antibody Levels For COVID-19?
While it is always great to know if you have had the virus or if you potentially have immunity to it, another great reason to test for Antibodies is that the U.S. Food and Drug Administration (FDA), in partnership with the American Red Cross, is encouraging people 17 and over who weigh more than 110 pounds to donate blood if they have a positive COVID-19 antibody test results.
Although more research is needed, they believe the transfusion of defensive antibodies may help severely ill people better fight and recover from a COVID-19 infection.
Want to learn more?
Click below to contact us and ask how we can help!
We are a leader in the delivery of intravenous micro-nutrient therapies.