Yes, it's possible for someone to be diagnosed with both flu and COVID at the same time, doctors say. Cases of people who have tested positive for both viruses, in what has now been coined "flurona," have been reported recently.
But despite some false portrayals online, the viruses have not merged to create a new illness. They remain separate infections.
"Flurona is a thoughtfully-named experience that can in fact occur. The flu virus and the COVID-19 virus are different enough that they're different variants and they both can occur at the same time," said Dr. Mark Loafman, chair of family and community medicine for Cook County Health.
Here's what we know so far about "flurona" and what to expect.
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Have there been any cases in the Chicago area so far?
Loafman said while he does not know of any cases in the Chicago area so far, he imagines "there are probably cases that have happened that we don't know, haven't tested for."
"It does not seem to be common, but I would expect it would become more common as flu now is starting to emerge," he said in an interview Friday.
Loafman said testing is increasing in the Chicago area "for not just COVID but for the whole respiratory panel," which could lead to reporting of some "flurona" cases. But he noted that testing for such cases is largely done when a patient is sick enough to need medical care.
Will flurona cause more severe illness than COVID?
Experts say the severity of a dual infection could cause more severe illness, but that's not always the case.
“A co-infection of any kind can be severe or worsen your symptoms altogether,” said Kristen Coleman, as assistant research professor at the University of Maryland School of Public Health.
"It certainly can be more severe when you're fighting a double infection, but the symptoms are so similar," he said.
What are the symptoms of flurona?
According to Loafman, there's no clear way to tell the difference between COVID or flu - and no real way to tell if you have both.
"We're making most of those diagnoses clinically," he said.
But while the symptoms are nearly identical, there can be subtle differences.
"One thing is the fever with flu, with influenza, tends to be a little higher, but that's subtle," he said. "So 101, 102 [degree] fever can happen with COVID, the fever can get a little higher with flu but it can also be low-grade. So other than that, you know, coughs, headaches, stuffy nose... congestion, some shortness of breath - those are all very, very common for both flu and COVID and I think for most of us, we wouldn't really be able to tell the difference."
Whether you were exposed or just aren't feeling well, experts say to assume that those who believe they might have a cold could have coronavirus, particularly as cases of omicron surge nationwide, leading to milder breakthrough infections.
"If you think it's a cold, if you think it's the flu, it's probably COVID," Chicago Department of Public Health Commissioner Dr. Allison Arwady said in a press conference late last month. "We need you to stay home if you're not feeling well."
Dr. Katherine Poehling, an infectious disease specialist and member of the Advisory Committee on Immunization Practices, told NBC News last month that a cough, congestion, runny nose and fatigue appear to be prominent symptoms with the omicron variant. But unlike delta, many patients are not losing their taste or smell.
The evidence so far, according to Poehling, is anecdotal and not based on scientific research. She noted also that these symptoms may only reflect certain populations.
Still, CDC data showed the most common symptoms, particularly with omicron so far, are cough, fatigue, congestion and a runny nose.
Overall, the symptoms for COVID reported by the CDC include:
- Fever or chills
- Shortness of breath or difficulty breathing
- Muscle or body aches
- New loss of taste or smell
- Sore throat
- Congestion or runny nose
- Nausea or vomiting
What should you do if you think you have flurona?
Unless you feel sick enough to seek medical help, Loafman said the guidance doesn't change.
"Follow the same guidance that we've been saying all along," Loafman said. "Stay home, stay away from others, and if you're sick enough, if you meet criteria to need help, then, you know, the clinical setting will sort out which testing to do."
It's those who need treatment for the viruses that the diagnosis is most beneficial because the way in which the viruses are treated is different, Loafman said.
How can you know if you need medical help? Loafman said there are some signs to watch for.
"Shortness of breath, a fever that won't go away, unusual chest pain - those are all symptoms that really require help," Loafman said. "Most of the complications are respiratory, so shortness of breath, difficult breathing."
The CDC urges those who have or may have COVID-19 to watch for emergency warning signs and seek medical care immediately if they experience symptoms including:
- Trouble breathing
- Persistent pain or pressure in the chest
- New confusion
- Inability to wake or stay awake
- Pale, gray, or blue-colored skin, lips, or nail beds, depending on skin tone
"This list is not all possible symptoms," the CDC states. "Please call your medical provider for any other symptoms that are severe or concerning to you."
You can also notify the operator that you believe you or someone you are caring for has COVID.
Can you get tested for both COVID and flu?
At-home tests for flu aren't as widely available as those for COVID-19, but some pharmacies offer testing for both viruses at the same time, Coleman said. Loafman argued, however, that such testing is most useful in a clinical setting.
"Don't rush out and try to find flu tests for yourself," he said. "We're not at the point yet where community-based testing is useful. Again, that's really reserved for people sick enough to seek health care and where we need to sort out how best to treat the sick patient. That's where flu testing really comes in."
In hospital setting, testing "for not just COVID but for the whole respiratory panel" are increasing across the Chicago area, Loafman said, which could lead to confirmation of "flurona" cases in Illinois. But he noted that testing for such cases is only done when a patient is sick enough to need medical care.
That is particularly important, Loafman said, as COVID testing shortages continue to be reported across Illinois and as hospitals battle a rising number of patients needing treatment.
Laboratories might also be able to screen samples for various respiratory viruses, including common cold viruses. But most do not have the capacity to routinely do this, especially during a COVID-19 surge, Coleman said.
What about vaccinations for both?
Just like you can get both viruses at the same, you can also get both vaccines at the same time.
The U.S. Centers for Disease Control and Prevention says it is safe to get a flu and COVID-19 shot or booster at the same time.
"It's really great to help people understand the safety of getting both vaccines simultaneously if you're going in," Loafman said. "You know, the immune system is incredibly talented and complicated and able to manage multiple exposures and antigens at the same time. Our bodies do that routinely in nature all the time. So having simultaneous injection of two or more vaccines at the same time, that doesn't affect the efficacy. There are a few certain vaccines where we do stage it but for most of the vaccines, including flu and COVID, take them as soon as you can get them."
Loafman adds that while both vaccines may not prevent infection entirely, they can help prevent serious illness from either virus.
When is the biggest risk period for flurona cases?
Loafman said flu cases are expected to continue rising through winter and early spring, but each year is different.
"Every year is a little different when it ends," he said. "It always burns out at some point in the spring. But we've got three months and maybe longer to go and there will be more cases and the more there is the more they spread and the more illness that we'll see."
Meanwhile, omicron COVID cases continue to surge to record levels in Illinois and across the country. Some experts predict the variant could peak this month.