Making Sense of Your COVID Test Results
Written by Leslie K. Hughes
Medically reviewed by Dr. Ariella Morrow
With more people getting tested for COVID-19 now than ever, it is more important than ever to understand what your test results mean (and don’t mean) so that you can be more confident in what is safe for you and others.
And we understand it can be quite confusing with things constantly changing. Thankfully, COVID testing is our specialty, so we are here to clarify any questions you may have about your COVID test results.
First, let’s talk about the different types of COVID tests.
Types of COVID Tests
Diagnostic
Diagnostic tests are the most common types of COVID tests. There are 3 main types. Chances are good that if you’ve visited a Sameday Health location to get tested for COVID, you’ve had at least one of these:
1. RT-PCR
This test is the gold standard in diagnosing COVID infection. It is a nose swab that gets sent to a certified lab for highly complex analysis. RT-PCR stands for Reverse Transcription-Polymerase Chain Reaction – and to break it down into basics, this test is like a tiny molecular copy machine that looks for actual genes of the COVID virus present in your nose.
Studies have shown that an RT-PCR test is approximately 95% accurate. Downside? Results take several hours to days.
2. Rapid Antigen
Like the RT-PCR, this type of COVID test is also a nasal swab used to find out if you currently are infected with the virus.
As the name says, you get results quickly, in about 15-30 minutes. You do lose a bit of accuracy with this kind of test, and studies show that a rapid test is about 72% accurate, sometimes better.
Why is this test less accurate? Well, instead of looking for virus genes like the RT-PCR does, the antigen test looks for proteins of the COVID virus. The test is generally only strong enough to turn positive when your nose is pumping out virus like a fire hose. If you have just a small amount of virus in your nose, this test is more likely to miss it.
Still, speed makes this test a great option for those who are in a pinch and need results ASAP.
3. Rapid PCR
This fast, high-accuracy test serves up the best of both worlds. Most clock in at 90%+ accuracy and churn out results in 30-60 minutes. However, these tests may not be readily available for everyone. Prices for Rapid PCR tests are higher than others because the technology and materials are expensive. Also, insurance companies might not cover this type of test, and some testing centers don’t have them at all. In the future, these tests are likely to dominate.
Antibody Testing
This test is not used to find out if you actively have the virus. It is a blood test that looks for antibodies your body has made whether from having COVID in the past, getting vaccinated, or both. Just because your body has antibodies, though, it doesn’t mean you’re totally immune – remember, “Antibody detection doesn’t equal antibody protection.” Especially with the Omicron variant, people with antibodies are still catching COVID but they aren’t as sick overall.
When to Take Your COVID Test
Timing is everything when it comes to getting accurate results from your COVID-19 test. The CDC advises that you get tested 3-5 days following potential exposure or when you start experiencing symptoms if that happens sooner. Updates to this timing might be around the corner, so keep up with changes in new variants as they crop up.
If you get tested the day that you potentially became infected with COVID or the next day, your test will likely show up negative. The virus needs time to “cook up,” what we call incubate (able to be detected). It can help to think of the virus infecting our cells like trying to get a factory up and running. Before your factory can make anything, it needs supplies and assembly time, etc. The same is true for COVID – the virus takes time to set up shop before showing up in your nostrils where our tests can find it.
Understanding Your COVID Test Results
It is really important to understand that test results are one snapshot in time. Our swab only grabs germs you have coming out of your nose at the very moment we are swabbing you.
So, if you test too early before your “virus factory” is in full production, there won’t be any virus bits floating around in your nose for our test to find. Even the best tests we have today wouldn’t be able to detect a COVID infection before its presence debuts in your nose.
If your COVID-19 test results come back negative, it means that the test didn’t find any virus in your nasal secretions (a.k.a. the swab sample they collected from inside your nose) at that moment in time.
So, if you have symptoms or were exposed to COVID, your body might need more time to turn out positive results and you should repeat the test in a couple of days. Even if your test came back negative, you must continue to wear a mask in public and follow the guidelines for social distancing.
If your COVID-19 test comes back positive, that means that the test did find the virus present in your nose. A positive result means that you are currently infected with COVID-19 and you need to isolate. False-positive results are relatively rare – especially during a surge.
Whatever your test results are, you should almost always talk to a COVID expert about your situation to figure out your next steps.
Isolating for Positive COVID Test Results
Isolation protocols were updated in Jan 2022. The bad news? It’s still a 10-day protocol. Good news: some people are allowed to ease up on restrictions partway through.
According to the CDC, you need to strictly isolate yourself from other people for at least 5 full days (day 0 is the first day of symptoms or, for people with no symptoms, use the date you got swabbed that came back positive).
This is true for everyone.
Then on days 6-10, some people may be able to “step down” into a less restrictive phase for the rest of the days: if you don’t have symptoms (never had them or they are better), then you are free to be around others but you need to wear a mask, whether at home or in public through day 10. That means you get back to your usual life on day 11. Need more clarification? Consult a COVID expert.
Some places, like California, add an additional safety precaution. California requires a negative test before you can get to that second, less restrictive phase of isolation. Not sure if that applies to you? Again, consult the experts.
The CDC also states that if you can’t wear a mask when around others, you should isolate yourself for a full 10 days until you are no longer contagious.
Some people may opt to test towards the end of their isolation period if it is required for travel or work.
Positive and Contagious Are Not Always the Same
Studies since early in the pandemic have shown that “people who have tested positive for COVID-19 are very likely to continue to test positive after 10 days [on PCR]. But they are not contagious.” In fact, some people can test positive with a PCR test for up to three months following their initial positive results. A better test to check contagiousness is actually the rapid antigen test.
Why can you still test positive months later? Because the PCR test is very powerful to pick up even tiny bits of virus genes leftover. And “even after your immune system neutralizes a virus, bits and pieces of the virus’s genetic material remain in your body – like DNA evidence left at a crime scene.” It is important to note that these remnants cannot infect someone, but they can cause you to test positive.
Sound strange? Probably to you and many people. But this phenomenon happens with all sorts of other virus infections all the time – such as the flu virus. We just don’t usually go around testing people for the flu virus after they have recovered.
Ever hear of a pop-up positive a few weeks after testing negative? Check with your doctor if you have symptoms but otherwise it’s nothing to worry about.
What’s Ahead for Testing in 2022
Look for updates to testing and quarantine protocols. That way, we keep up with changes in the virus variants and can curb the spread. Omicron so far appears to be a great masquerader, with slightly different symptoms. It also appears to need repeat testing to be sure you’re negative.
The virus is showing up in our nose at less predictable days after exposure – the variants are getting more wiley and our bodies also handle the virus differently after vaccination. We will continue to share more on these developments in future posts.
To help you keep yourself and others safe and minimize the spread of COVID-19 as much as possible, always do the following things:
Watch for symptoms of COVID-19 – even mild congestion, runny nose, sore throat, headaches, back pain as well as fever, cough, shortness of breath, and more
Err on the side of safety and stay home if you are sick
Repeat your test in a couple of days if at first, your results are negative
Wash your hands regularly
Wear a mask in public – reach for medical masks, rather than cloth, when you’re indoors
Practice social distancing (at least 6 feet)
Get a booster shot when you're eligible
