Think you have COVID-19? Here’s when to test, how to isolate and what you should know

Health experts talk PCR, rapid and at-home testing, how vaccine comes into play

Phlebotomists Meghan O'Rorke takes information from a patron prior to collecting a sample during free drive-thru COVID-19 testing at Sycamore High School Tuesday afternoon. The testing at this site by HR Support is offered through a partnership with the Illinois Department of Public Health, the DeKalb County Health Department and Sycamore School District 427.

For a non-exhaustive list of testing sites, go to

With the highly contagious omicron variant of COVID-19 surging across the state, many in northern Illinois are wondering when to get a test.

While existing COVID-19 vaccinations remain the best way to prevent severe infection and hospitalization, the omicron variant is likely to occur in many, despite inoculation.

Here is what experts say about best practices for testing and isolation, and what should you do if you test positive:

What symptoms should I look for?

Unlike previous strains of COVID-19, the omicron variant might not present with a loss of taste or smell. Instead, many are reporting feeling cold or flu-like symptoms, according to the U.S. Centers for Disease Control & Prevention.

That doesn’t mean other strains like delta aren’t still out there, or that those symptoms won’t be present.

In general, watch for: fever or chills, cough, shortness of breath or difficulty breathing, fatigue, muscle or body aches, headache, new loss of taste or smell, sore throat, congestion or runny nose, nausea or vomiting or diarrhea.

People with compromised immune systems or other health issues, such as older adults with heart or lung disease or diabetes, are at higher risk for more severe COVID-19 complications.

What should I do if I believe I’ve been exposed to the virus?

Monitor your symptoms, and wait at least five days before taking a test to ensure that, if you are positive, it will show up in a test result, said Lisa Gonzalez, public health administrator with the DeKalb County Health Department.

“If your grandma just tested positive, you should really wait a full five days before getting tested because your viral load probably won’t be high enough to detect, but in the meantime you should be quarantining,” Gonzalez said.

If I’m vaccinated and boosted, do I still need to get a test?

“Yes, we believe that you do,” Gonzalez said. “There could be breakthrough cases and could mean that you spread [COVID-19] to others and not even know you have it.”

If you know or suspect you’ve been exposed to COVID-19, health officials recommend waiting between five to seven days until testing, to ensure the virus has developed to be detected by tests.

Why should I get vaccinated if vaccinated people can still contract COVID-19?

Vaccination remains the strongest form of protection against the virus, experts said.

There are a myriad of factors that could contribute to a person who’s vaccinated contracting the virus (a breakthrough case). But those factors – the prevalence of the virus in a community, a person’s social behaviors or ability to social distance or mask in the workplace or at school, the arrival of highly contagious omicron and delta strains – also impact the unvaccinated, who have less immune protection against severe illness.

That’s why mask-wearing and testing is an important step for everyone, experts said.

According to data reported by the CDC collected from case studies in South Africa and the United Kingdom when omicron was first detected, two doses of an mRNA vaccine (Pfizer and Moderna) offered about 35% chance of protection against omicron. Two doses plus a booster increased that infection protection to 75%.

“So we know they work, we know the booster provides additional protection,” Gonzalez said.

When is the best time to test after possible exposure? Or if I start feeling ill?

Don’t test immediately after exposure.

“One of the testing challenges we’re experiencing is that people need to understand if they are a close contact to a positive case, they should not test right away,” Gonzalez said. “They should quarantine and wait five days to get the test done.”

It’s important to remember to isolate yourself from others if you start to feel ill or if you’re waiting on a test result, even if you don’t know yet whether it’s COVID-19.

What if I test positive and live with other people?

The CDC recommends isolating in a separate room if you can, and using a separate bathroom. Quarantine for at least 5 days and then if you have to be around people, wear a mask that fits around your face and nose well.

Close contacts include people within 6 feet of you for a cumulative 15-minute period over 24 hours.

Are rapid tests reliable? When should I seek a PCR test instead?

It depends on when you test, and how long it’s been since you were exposed, experts say.

At-home tests also are rapid, and a negative result does not necessarily rule out infection, according to the CDC. PCR molecular tests are sent to the lab and detect whether genetic material from COVID-19 is present in the sample, according to the Mayo Clinic. A rapid antigen test looks for the existence of certain virus proteins in the sample.

“If they get a rapid test too early, it may not show positive,” Gonzalez said. “Rapid antigen tests work best when it’s a symptomatic person. So if you’re not symptomatic and you’re using an antigen test too early, it could be problematic.”

If you are experiencing cold or flu-like symptoms or have a known exposure to the virus and you get a negative rapid antigen test result, health officials recommend you continue to isolate and seek a PCR test.

It’s known as the gold standard for a reason, Gonzalez said.

What about masking?

According to federal health experts, it’s important to practice proper masking when in crowds, especially when you don’t know who is vaccinated and can’t maintain social distance.

Unlike the early days of the pandemic, higher quality masks are available to the general public, though at a steeper cost than a cloth one. Doubling up a cloth mask atop a surgical mask is a good idea as omicron spreads, Gonzalez said. There also are KN95 and N95 masks, five-layered protections which filter out a higher percentage of germs than a cloth mask alone.

At the very least, you should be covering your face when you go out and are around people. In Illinois, an indoor mask mandate remains in place.

“Wear a mask and wearing it correctly and consistently is really important,” Gonzalez said.

There’s so many tests out there. How do I know which one is the best for me?

PCR tests, taken by a nasal swab and sent to a laboratory with results expected in a day or two “continues to be the gold standard” for accuracy, Gonzalez said.

Because of the onslaught of virus cases and post-holiday tests, however, significant delays are being reported for lab test results.

Local pharmacies, pop-up testing sites in DeKalb and others at clinics in Sycamore offer such tests. Some also offer rapid testing, usually done by a BinaxNOW test, another nasal swab that tests for antigens, with results in about 15 minutes. Locations such as Hy-Vee pharmacies or Physicians Immediate Care in Sycamore could require a cost associated with rapid tests, or if a doctor’s visit is included.

Rapid antigen tests work best when symptoms are present, Gonzalez said.

Some places offer walk-in tests, some accept by-appointment only, with availability varying by location and by time of day.

For at-home test swabbing, both experts recommend following the instructions on the box.

What if I test positive using an at-home COVID-19 test?

If you test positive with any COVID-19 test, you should continue to isolate, monitor your symptoms and let those around you know that you have the virus so they can take appropriate action. Think about where you’ve been in the past 48 hours, experts say.

“Keep in mind when an at-home test is administered, the health department doesn’t know about it,” Gonzalez said.

That’s why it’s important to educate yourself on what to do if you test positive, since you won’t be receiving a text from the state health department with guidance on next steps.

“If you’re symptomatic and at home and you can’t get access to other testing, that’s a great time to use [at home] tests,” Gonzalez said.

The CDC recommends staying home or isolating for five to 10 days after a positive test result, wearing a mask when you have contact with others and talking to your healthcare provider.

What if I can’t find a test? Or what if my result is delayed?

“Sit tight is the key,” said Dr. Michael Kulisz, chief medical officer at Northwestern Medicine Kishwaukee and Valley West hospitals. “There is a delay in testing just because of the sheer volume.”

Stay at home, monitor your symptoms, and limit exposure to others, he said.

What’s the best at-home test to use?

Places such as Walmart and Amazon offer BinaxNOW kits online for people to administer to themselves at home. The Walmart in DeKalb sells such kits for $14, which includes two tests per kit, though stock remains low or out.

Is an at-home test kit accurate, can the results be trusted?

Yes, to some degree, Gonzalez said.

“At-home test kits definitely serve a purpose,” she said. “The BinaxNOW tests are generally less reliable than the PCR, but they still have a relatively high accuracy and allow for fast results. That’s why people like to use them.”

What happens after I test positive with a lab test result?

The Illinois Department of Public Health recently announced that the state model of contact tracing would be evolving into an automated system: Those who receive a positive result from a COVID-19 test will receive an automated text alerting them to next steps for notifying close contacts.

It’s part of a plan, according to the IDPH, to centralize contact tracing and case investigation across the state. Local health department staff won’t be tasked with tracing exposure points for every single case as they did before.

That means it’s up to the person who’s contracted the virus to let others around them know they might’ve been exposed, Gonzalez said.

When someone tests positive – using a lab test not an at-home test – they’ll receive the following text from the State Surge Center: “IDPH COVID: There is important info for you. Call 312-777-1999 or click:

“The link will take you to a website full of information on case investigation and contact tracing, isolation and quarantine,” Gonzalez said. “It will also instruct you that you should be looking back 48 hours to determine who might be close contacts. So it’s really putting it on the individual for and providing information for what they need to take appropriate steps.”

When should I seek emergency medical care if I’m COVID positive?

The CDC recommends seeking emergency medical care if you are having trouble breathing, persistent pain or pressure in your chest, new confusion, the inability to wake or stay awake, or pale, grey or blue-colored skin, lips or nail beds depending on skin tone. If you have other serious medical conditions and contract COVID-19, you should consult a doctor.

If you call 911, the CDC asks that you notify the operator that you have COVID-19 so first responders can treat you accordingly.

Emergency departments across northern Illinois are feeling the strain of a winter illness season compounded by another surge of COVID-19, Kulisz said.

“As volumes do go up, there may be longer waits for the patients,” Kulisz said. “And if they could just bear with us, we’re all in this together. Our goal is to give them the highest quality of care at the most appropriate time and as quickly as possible.”

While Northwestern Medicine and other health systems are asking people to not come to the ER for a COVID-19 test and limit visits unless it’s an emergency, you should know when to go to the doctor if you’re having a severe case of COVID-19.

“If you were just exposed to somebody with [COVID-19], to come in that day or the day after really doesn’t make a difference,” Kulisz said.

When is it safe to stop isolating after I’ve been ill with confirmed or probable COVID-19?

The new CDC guidance on isolation and quarantine does not apply to healthcare personnel, and people should continue to look first to local and state guidance, according to the CDC’s website.

On Dec. 27, the CDC issued new guidance related to isolation protocols amid viral exposure and infection: Namely that if someone tested positive for the coronavirus and was asymptomatic, or didn’t experience any symptoms, they could shorten their time in quarantine from 10 to five days. The CDC asks that for the remaining five days, those who tested positive without symptoms be vigilant about proper mask-wearing while out and about.

“Based on information they’ve released so far, the CDC is looking at the science behind when individuals are most infectious,” Gonzalez said. “So they’re saying that 48 hours before symptom onset and then for those few days after symptom onset. I believe in the science that’s out there. I believe in the scientists who are working to try to evolve with this pandemic.”

It seems like COVID-19 is everywhere. What are ways I can lower my risk of exposure?

Gonzalez said the difference of risk is a matter of environment and vaccination status.

“We’ve been saying the same message forever, get vaccinated, get boosted if you haven’t already,” Gonzalez said. “Find that booster shot this week, you could probably still do that. If you’re unvaccinated, avoid those family members and friends who may be most at risk. If you’re not vaccinated, the risk is just pretty high based on the community spread, so consider that when you’re planning to go to those gatherings.”

If a person, regardless of vaccination status, has known exposure to someone who contracts the virus, or if they’re putting themselves in high-risk situations such as where they can’t socially distance or wear a mask, then the chances of infection rise.

If you are in public places without a mask, attending an event for a long period of time, especially if you can’t socially distance, your chances for contracting the virus increase.

It’s important to remember that, despite the prevalence of the virus, there are still steps we can all take to limit exposure and lower community spread.

“The important thing people have to understand, even if they are vaccinated and test negative and still go ahead and socialize, is to just use common sense,” Kulisz said. “Continue appropriate masking, wash your hands, and vaccines decrease the severity of the disease.”

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