When you hear the word “COVID -19 testing” what comes to mind? I have this vivid image of a cotton swab being pushed up my nose. But what exactly is testing? Why is it so important? And what are the types of testing available for our use?
We’ve all heard that testing is important but why? To summarize a supplementary article, COVID testing “leads to quick identification of cases, quick treatment for those people and immediate isolation to prevent spread” (Dr. Eduardo Sanchez). When discovered at an early stage, COVID will be less a threat to a person because doctors can plan accordingly while COVID is still less severe. Even when a person discovers they have COVID not as early as hoped, testing helps to identify anyone who came into contact with infected people so they too can be quickly treated. Contact tracing would not be possible without testing because a person would never know if they are spreading the virus. The only way to be better safe than sorry is to get tested. Someone may show symptoms that are COVID-like but there is still a chance that it could be a common cold, or allergies. It is important to confirm COVID suspicion.
Now that we know why testing is important, what kind of testing is out there? What I found in this FDA article is what I like to call a family of tests; there are numerous different tests to take.
To start things off, let’s talk about Diagnostic testing. Diagnostic testing shows if you have an active coronavirus infection. As of right now, there are two types of diagnostic tests: molecular and antigen tests. Molecular tests detect the virus’ genetic material in a sample from the patient’s nose or throat. This is where test results will take longer because they are sent to labs. From there, the lab essentially converts the virus’s RNA into DNA, and then make millions of copies of the DNA to be processed in a machine. The test is “positive” for infection with SARS-CoV-2, the virus that causes COVID-19. Examples of molecular diagnostic tests include nucleic acid amplification test (NAAT), RT-PCR test, and the LAMP test. Next, there is Antigen diagnostic testing. Antigen tests provide results from an active coronavirus infection faster than molecular tests. The downside to these tests are that they have a higher chance of missing an active infection. Sometimes an antigen test may come back negative, but a doctor might still order a molecular test to confirm.
Different from Diagnostic Tests, there are Antibody (different from Antigen) tests. These tests looks for antibodies that are made by your immune system in response to a threat, such as a specific virus. As we learned in biology class, antibodies can help fight infections. These tests are taken by finger stick or blood draw, and the results are quick. The antibody test only shows if you’ve been infected by coronavirus in the past. But do antibodies help diagnose COVID-19? As we learned in class about the Immune System, our body can fight pathogens, bacteria, and viruses that we have been previously exposed to. While this was a popular belief earlier on in the year, sadly, researchers do not know if the presence of antibodies means that you are immune to COVID-19 in the future. It is possible to contract COVID-19 for a second time, therefore adaptive immunity does not apply.
The most common testing that I knew of before researching was rapid testing. Rapid testing can be both a molecular or antigen diagnostic; a doctor uses a mucus sample from the nose or throat. The test can also be taken at home only by prescription of a doctor. The results are available in minutes. There is also saliva testing where a person can spit into a tube; this also keeps the doctor or worker safer from the potentially infected person.
Testing is the best way to keep yourself and those around you safe. While testing is still not 100% accurate, there is currently no better way to confirm if someone has COVID-19 unless he/she get tested. With this pandemic, we can never be too safe!