Why are people testing negative for COVID, and then testing positive days later?
Odds are, you know someone around Kansas City who has tested positive for COVID-19 in the past couple weeks. With local medical officials saying COVID-19 patients are overwhelming their hospitals and record-breaking daily new case numbers, the virus is here in full force.
So many people are trying to get tested, and one question we’ve heard from readers and wanted to learn more about is why so many people seem to be testing negative at first, to only then test positive days later.
We reached out to Dr. Ginny Boos, director of infection prevention at Saint Luke’s Health System, who provided insight into why this may be the case with this new wave.
Test negative, then positive? How? Why? Me? No way!
Boos said there could be a couple of reasons, but the most common reason is that people may be testing too soon.
She said that she’s heard of a lot of people who have felt anxious when they found out they were exposed to someone else who tested positive, especially if that person was already vaccinated.
Boos said people in this situation often rush out to take a rapid antigen test before they have any symptoms. She pointed out that these rapid tests are really time-sensitive, and someone could’ve simply tested too soon before the test could detect any of the virus.
Symptoms related to omicron can also be flu-related, so when someone takes an at-home COVID-19 test, the chances of having a false negative are pretty high. If you test positive, we created a helpful guide on what to do.
When is the best time to get tested?
If you already feel sick: If you’re having symptoms and you can get scheduled for a test, or if you can secure an at-home test, testing as soon as you can would be ideal.
If you’re not showing symptoms: Wait three to five days, but closer to five days is a good marker for taking a test to allow the virus to fully “incubate.”
What test is the right test?
We asked Dr. Boos for recommendations on what test to take in a given situation. This is what she said.
You’re going to a large gathering:
If it’s to gain admission, an at-home COVID-19 test is your best test. The results are back in 15 minutes, and while there’s the risk of a false negative, you should use it when it’s available for this kind of situation.
Now, let’s say that you go to this large gathering, and then you find out later that someone you did karaoke with tested positive. Boos said the best test now is the PCR test, but that you should wait until day five after the day you were exposed to that person to take it.
You can use the same process with an at-home test, but as she mentioned before, there is a risk of the rapid results showing a false negative. While the results of a PCR test will take longer to get, Boos called it the gold standard because it’ll pick up what a rapid antigen test misses.
You were exposed to someone who tested positive, and now you aren’t feeling well:
If you develop symptoms, go ahead and get tested. If you take an at-home test and it comes back negative, you need to follow that up with a PCR test, or you can just take the PCR test first to guarantee more accurate results, Boos said.
If you believe you had minimal contact with the person who tested positive, and you aren’t showing any symptoms, you should still take a PCR test, as these tests can pick up parts of the virus that a rapid antigen test might’ve missed.
Symptoms help determine if you have COVID-19 or not, but it can be tricky with flu season. A lack of taste or smell is a significant symptom in figuring out if you’re battling the common cold or the coronavirus.
You can’t find a test, but you’re not feeling well:
Tests aren’t guaranteed to be available absolute with the increase in demand for them. Boos said it’s safer to assume you’re positive and isolate yourself if you’re not feeling well.
“I want to emphasize the health system across the metro and really across the country, are really experiencing some pretty intense patient loads,” Boos said. “If you’re unable to get a test and you are symptomatic, whether you’ve been exposed or not, just assume that you have the virus, and quarantine for the next five days.”
Testing at day five is a good marker, but unless you’re experiencing severe symptoms such as shortness of breath, confusion, high fevers or any life-threatening symptoms, you can stay home and not expose anyone by self-quarantining for the next five days. If you are experiencing these kinds of severe symptoms, you should go to the hospital or seek immediate medical care.
Vaccines are still the most important protective measure
Both Boos and Lindsey Stitch, the director of media relations with Saint Luke’s Health System, emphasized the importance of getting fully vaccinated and receiving a booster shot when you’re eligible. The majority of people that end up hospitalized are unvaccinated.
With omicron providing so many breakthrough infections, Boos said symptoms are mild in vaccinated people compared to the unvaccinated.
“It behooves us to encourage people to get vaccinated, get boosted, use the best tool, the gold standard tool out there to protect yourself,” Boos said.
Here’s our guide to where you can find a vaccine around Kansas City.
Do you have other questions about testing and COVID-19? Ask us at kcq@kcstar.com or with the form below.
This story was originally published January 6, 2022 at 3:26 PM.
