Testing for COVID19 is extremely important for fighting the spread of the virus. Whereas we typically attribute fighting COVID with vaccines, much of the work globally is done at the testing level: who is infected, how is the virus spreading, and what we learn when the virus grows or diminishes in a given area. All of these questions are answered through testing.
So how is this testing being conducted? You’ve likely heard about or experienced various types of COVID tests—nasal swabs or saliva tests, minute-clinic testing or laboratory testing—but how much do you know? Why are some tests used instead of others? What, exactly, are they testing? Which is most accurate? We’ll take a look at the FDA approved COVID test list to learn more about testing practices.
When doctors and scientists test for viruses, they look for evidence in a variety of different forms. For example, you’ve heard of antibody tests for COVID-19: this is a form of testing that looks for the antibodies produced when fighting a specific virus. Each of the types of COVID tests look to identify different pieces of evidence.
Antigen tests look for evidence of COVID-19 in the form of proteins on the surface of the virus. When these are detected, it’s a positive indication the patient is currently infected. A nasal swab is used to collect a sample from the patient, most accurately when the patient is showing symptoms, and this is tested for the protein. Because of the antigen test’s reduced accuracy, doctors recommend symptomatic people who test negative repeat the process with a more accurate PCR test.
You’ve likely heard about at-home tests or rapid testing: these are quick, cheap, helpful ways to detect the virus. Most of these are classified as antigen tests. These tests are so helpful because of their accessibility: more people are able and willing to produce these results to scientists and doctors. The risk is the accuracy. Antigen tests produce more false positives and false negatives due to when and what it’s measuring.
The most common type of molecular COVID test is the PCR test. Molecular tests differ from antigen tests. Rather than looking for proteins related to infection, PCR looks for genetic material that indicates infection. And that means the samples have to be tested in a laboratory, with proper personnel and equipment. While these tests take far longer to complete, they reduce the possibility of false negative/positive results.
Anytime your body tries to fight a virus, it produces antibodies that are still present in the body after the infection. Antibody tests—also called serology tests—are helpful for fighting COVID because it allows scientists and doctors to make all sorts of observations about the virus. How many people were previously infected, what percentage were asymptomatic (not showing symptoms), possible spread based on the patient’s contact with others—even though the patient no longer is at immediate risk, there’s plenty of value with these tests.
Samples from patients are required for any form of COVID-19 testing, and the two best samples come from saliva or nasal swab. While there’s still some conflicting opinions, it’s generally believed that saliva testing is somewhat less sensitive than nasal swabs. Nasal swabs have been considered the gold standard, but they require more supplies, and they put healthcare workers in close proximity with potentially infected patients. With either test, the real issue is viral load, and how much evidence can be detected within a given patient. Not to mention the lungs can show evidence of the virus longer than the mouth. So there are more factors involved than just coronavirus test procedure and methodology.
Testing for COVID continues to evolve as doctors and scientists learn more. Take the fact, for example, that at-home rapid testing wasn’t available less than a year ago! And more testing needs to be done to learn more about the virus and more about testing techniques. Testing remains one of the most critical tools for continuing to fight COVID.
That’s why BioCollections Worldwide continues to be instrumental in COVID testing and researching. In fact, we were already developing COVID tests prior to the pandemic, understanding its potential, and we continue to provide accurate testing and analysis moving into the future of fighting COVID.
With over twenty years’ experience, over six locations in the US and more affiliates and subsidiaries internationally, we look to provide exceptional testing wherever needed. When you’re looking for high quality and trusted COVID-19 testing, BioCollections Worldwide is the source.