Is it COVID-19, the Flu Or A Cold? How To Tell The Difference

·6 min read

As the annual respiratory virus season kicks off, it can be difficult to distinguish between colds, the flu, allergies and COVID-19 because their symptoms can be so similar. All of them can cause symptoms like fatigue, congestion and sneezing — but without knowing what’s making you sick, it can be hard to take care of yourself.

When it comes to COVID-19, the BA.5 omicron subvariant is still causing the vast majority (more than 83%) of cases in the U.S., according to estimates from the Centers for Disease Control and Prevention. That's why it's important to get the new updated COVID-19 booster, which protects against the BA.4 and BA.5 variants in addition to the original coronavirus strain.

And, after a few years of surprisingly mild flu seasons, early signs suggest that this fall and winter could see the return of influenza cases to more normal numbers. To get the most protection, you should aim to get your flu shot by the end of October, experts say.

If you start to feel like you might be getting sick, you shouldn't hesitate to take an at-home COVID test if you start to feel symptoms, Dr. John Torres, NBC News senior medical correspondent, told TODAY.

"If you start getting sick, essentially you have to assume it's COVID unless proven otherwise," he explained. "And by that I mean make sure you isolate yourself (and) get a test to make sure it's not COVID." If you test negative, at that point you can start to consider the cold or flu, but you should assume it's COVID-19 until then.

"You notice there's a lot of overlap in those symptoms, and that's why it can be so hard to tell the difference between all of them," Torres said. "But there are a few differences."

Related: COVID-19 booster side effects: What to expect and how to manage

Here's what to look out for:

Common cold symptoms

With a cold, symptoms tend to build up over a few days. Torres said to look out for the following:

  • Runny or stuffy nose

  • Sore throat

  • Cough

  • Congestion

Common flu symptoms

Unlike with the common cold or COVID-19, flu symptoms tend to come on suddenly and can feel severe. “The flu hits you right away,” Torres explained. “If you’ve ever had the flu, you know you get to a point where you can’t get out of bed.”

Here is what to look out for:

  • Fever

  • Cough

  • Sore throat

  • Runny or stuffy nose

  • Body aches

  • Headaches

Common COVID-19 symptoms

The signs of omicron and its subvariants tend to be similar to previous COVID-19 strains, and they might include mild cold-like symptoms. But there are some slight differences.

People don't report a loss of taste or smell as much with omicron subvariants as with previous variants, Torres said. “But people are reporting night sweats, which is a very strange symptom that they say they’re having.”

  • Cough

  • Fatigue

  • Headache

  • Sore throat

  • Fever

  • Body aches

  • Runny nose and congestion

  • Night sweats

  • Less likely to have a loss of taste or smell

Common seasonal allergies symptoms

Many people who regularly get seasonal allergies know their usual symptoms and have their own go-to strategies to manage them. But we’re still in a pandemic, so if you start to feel symptoms, it’s worth trying a rapid test for COVID-19 just to be sure, Torres said.

He also noted that, while there is some overlap with COVID-19 symptoms, allergies don’t cause fever. And the fatigue is typically milder with allergies than what comes with a coronavirus infection.

  • Itchy or watery eyes

  • Itchy throat

  • Itchy ear canals

  • Stuffy or runny nose

  • Tiredness or fatigue

When should you get tested?

"One of the biggest things is you want to avoid self-diagnosing. That means if you're displaying any symptoms, you want to go ahead and get tested," Torres said.

When you get tested, depending on your symptoms and what your COVID-19 test results are, you might also get tested for the flu or strep throat.

You can also get more than one illness at a time (like "flurona"), or you can get allergies alongside COVID-19 or another condition. "What I tell people is, 'We're in a pandemic. Test for COVID. Rule it out first and then think about the other things,'" Torres said.

With omicron and its subvariants making up most of cases right now, it's good to know that rapid tests generally still work for omicron, TODAY recently reported. But it's too early to know how well they work against omicron subvariants, Dr. Amy Mathers, associate professor of medicine and pathology and associate director of clinical microbiology at the University of Virginia School of Medicine, previously told TODAY.

That's why, if you get a negative rapid test result, you can't automatically assume you don't have COVID. So, if you're having symptoms that could be due to COVID-19, a cold, allergies or the flu and test negative, experts recommend taking another test two to three days later because you'll have a better chance as testing positive if you do have COVID.

Best cold, flu, allergy and omicron home remedies

The best home treatments for any of these illnesses depend on the exact symptoms you're experiencing. Torres shared some advice about over-the-products that can help, but you should always check with your health care provider first.

  • Fever and body aches: Use pain- and fever-reducing medications such as acetaminophen and ibuprofen.

  • Congestion: For a stuffy nose, use an over-the-counter medication like guaifenesin (Mucinex). If your congestion is due to allergies, try a nasal steroid spray or non-sedating antihistamine.

  • Fatigue: Make sure you stay hydrated, get enough electrolytes and rest up. "Sleep is one of your biggest aids you can use right now that lets your body recuperate and regenerate itself so it can protect you and it keeps your immune system strong," Torres said.

  • Difficulty breathing: If you experience any difficulty breathing or shortness of breath or if your symptoms get worse rather than improving, you should speak with a doctor, Torres said.

Is it too late to get vaccinated?

When it comes to COVID-19, know that it's not too late to be vaccinated. And, if you haven't already, you can now get your updated bivalent COVID-19 booster and this year's flu shot. In fact, you can get them both at the same appointment.

COVID-19 vaccines take a few weeks to build up an immune response and provide the most protection. So if you haven't gotten those vaccines yet, getting them now is the best way to be protected in the future.

Children as young as 6 months are now eligible to be vaccinated in the United States, and everyone 5 and up who's had their first round of vaccination qualifies for the first booster shot. Adults age 50 and older and people 12 and up who are moderately or severely immunocompromised qualify for a second booster shot.

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This article was originally published on TODAY.com