What are my options?
I’ve recently been thinking about the challenges of understanding what options are available for COVID-19 testing.
“My sister got her test results back in 30 minutes but I heard most take around 6-8 hours to hear back.”
To be honest, as an individual working on COVID-19 research – I haven’t put much thought into how the testing options have continued to evolve and what it all means. So this is my attempt to provide a little bit of info regarding COVID-19 testing.
One of my first recommendations for anything/everything COVID-19 related is to check the CDC page. Although the info they provide may not answer all your questions, it’s probably the best way to start.
Here’s the sitch:
According to the CDC there are two main types of tests….
- Viral test
- Antibody test
What does that mean?
Well, in a hospital setting, a viral test is used to confirm current infections. Now the question may arise, what type of viral test? I’ll get to that in a second but let’s move on to the next logical thought – what happens in a non-hospital setting? It’s also quite possible/likely that you are also getting a viral test done. The important distinction to make is between the viral tests (that test for current infection) are not equated to antibody tests (that test for previous infection).
A little bio 101 if I may – when the human body is exposed to foreign material (virus, bacteria, etc) the “normal” response is to activate/trigger the immune system – i.e. get rid of it. Hope to do a more detailed post about the biology/physiology of the immune response.
Now let’s get back to COVID-19 testing…
Antibody testing – not all that useful for determining current infections as I’m not sure if there is any research/information regarding if the immune system develops antibodies (at a detectable level) while an individual is still in the “infectious” stage of COVID-19. To clarify, the “infectious” stage is at which point an individual infected with the SARS-COV-2 virus is still “shedding” virus that could potentially transfer to another individual. Long story short – suspect you have COVID-19? Don’t get an antibody test.
How do you know which is which? My recommendation is to do a little bit of research on the options you have available in your area and honestly, if you ask the company or individual that is providing the test – they should be able to tell you.
But let’s take a stab at some ways I can help make the research a little bit faster/easier.
- Take a look at any resources/info your state department of health provides
Let’s walk through the state of Hawaii.
After clicking on “COVID-19 State of Hawai’i Portal”
Let’s check out CVS/Longs drugs because it seems to be the most widespread option that many individuals may have access to.
It looks like CVS provides two testing options
- Molecular lab test (PCR/NAAT) – this is a viral test (the type of test most often used in hospital setting)
- Rapid-result test
Ohhhhh, interesting. This provides a great opportunity to showcase a somewhat misleading webpage that I’m almost certain is quite common. What do they mean by rapid-result test? Certainly a “rapid-result” is much better than waiting the 1-2 days mentioned for the molecular lab test. Well the question you should ask is “what type of test is giving you this rapid result?”
If you scroll down a little further CVS provides an FAQ page. After sifting through the questions you’ll see the question “What type of test is performed?” As you continue to read the answer you’ll see
“Most rapid-result testing locations perform antigen testing. Limited rapid-result locations and all drive-thru lab testing locations perform PCR/NAAT testing.”
Wait a minute, what is antigen testing? So far, we have only discussed “viral” testing and “antibody” testing.
Simply put, the “Molecular lab test (PCR)” is testing for genetic material from the virus and seems to be the preferred method of testing in hospitals – likely due to reliability and repeatability. The antigen test “looks for molecules on the surface of the virus.” MIT Medical does a great summary.
Now it seems reasonable, a faster test means there is an increased probability that the result may not be as reliable. The FDA has a great comparison of these differences, take a look.
So, should you not get an antigen test? The choice is really up to you, my personal opinion is to approach COVID-19 testing with a balance perspective.
Would the “best” option be to get a PCR test? Well, if you’re going to CVS and it’s not a problem to wait 1-2 days then yeah maybe.
If you are concerned that you have been exposed and are in a pinch to get tested quick – well a Rapid antigen test might be the way to go because “less” reliability does not mean unreliable. I should also note I’ve been tossing the term reliability around but a more detailed discussion would be key to really understanding what’s meant. For now, I’d say antigen tests are “reliable” just probably not quite as “good” as the PCR testing.
To wrap this up, viral testing (both PCR/NAAT and antigen) is a great option for those wanting to confirm current infections. I’d be curious to explore if there are currently saliva based viral tests because the question would be are those as accurate as the swabs – but who knows if that question has been answered yet.
Antibody test – not ideal for looking for current infections as I’m sure you knew prior to reading this but might be a good way to confirm what type of response you have had if you received the COVID-19 vaccine. Here’s a looonnngggg and exhaustive list of current COVID-19 tests if you’re curious to take a DEEP dive.