How to Know if You Have a Cold or the Flu (and Does It Really Matter?)

There are a few key differences between cold vs. flu symptoms (spoiler: a stuffy nose probably means you've got a cold).
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They call it cold and flu season for a reason: Both viruses are widespread during the fall, winter and early spring — and often, it can be tough to tell what you actually have.

But it's always worth taking a closer look at your symptoms when you're feeling under the weather, because colds and the flu pose different health risks, and in some cases, they may need to be managed differently.

Here's how to figure out what you might be dealing with and what you can do to start feeling better. Plus, the right way to handle it all in the age of COVID-19.

Cold vs. Flu: What's the Difference?

The cold and the flu are respiratory illnesses that have a lot in common. Both are caused by viruses, are easy to catch when you come in contact with an infected person and trigger similar symptoms.

But they're different in two important ways. First? The flu tends to hit you a lot harder.

"If you have a cold, you may feel a little under the weather. But influenza generally causes a more severe constellation of symptoms that make it hard to go about your day," says Joshua Septimus, MD, FACP, Medical Director of Houston Methodist Primary Care Group's Same Day Clinic Program.

Also important: The flu poses a much greater risk for complications — especially for those who are over 65, have a chronic health condition like diabetes or asthma, are pregnant or are under age 5, per the Centers for Disease Control and Prevention (CDC).

While most healthy people recover from a case of the flu without a problem, the virus has the potential to cause pneumonia as well as inflammation of the heart, brain or muscles and even extreme inflammatory responses that can lead to sepsis. Indeed, until COVID-19 emerged, flu was one of the top 10 causes of death in the U.S., per the CDC.

In short? Colds rarely cause any serious setbacks. But the flu could potentially land you in the hospital — and even become life-threatening.

So if you suspect that you have the latter, it's especially important to prioritize helping your body get better and talking with your doctor about reducing your risk for possible complications.

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Spotting the Symptoms

That first tickle in your nose or throat usually tips you off to the fact that you've got a bug brewing. But knowing whether you're dealing with a cold or the flu isn't always straightforward.

"The general difference between the two syndromes is severity," Dr. Septimus explains. You can probably power through your day with a cold. But the flu might make it hard to even get out of bed.

Some symptoms are also more common with one virus than the other. Both colds and the flu can cause respiratory symptoms like coughing or chest discomfort, sneezing and a sore throat. But the flu is more likely to affect the rest of your body too — with things like a fever, aches, chills, headache and an overall feeling of weakness, per the CDC.

And runny and stuffy noses tend to mostly affect those with colds, says David Cutler, MD, family medicine physician at Providence St. John's Health Center in Santa Monica, California.

Finally, pay attention to how your symptoms showed up. Colds tend to develop gradually over the course of a couple days, while flu symptoms often hit you all of a sudden, notes the CDC.

Cold vs. Flu Symptoms

Symptoms

Cold

Flu

Symptom Onset

Gradual

Abrupt

Fever

Rare

Common

Aches

Slight

Common

Chills

Uncommon

Fairly Common

Fatigue or weakness

Sometimes

Common

Sneezing

Common

Sometimes

Cough

Mild to moderate

Common

Stuffy Nose

Common

Sometimes

Sore Throat

Common

Sometimes

Headache

Rare

Common

Source: Centers for Disease Control and Prevention. (2020). "Cold Versus Flu"

How to Treat Cold and Flu

There's no cure for a cold or the flu, so when you're sick, it's all about managing your symptoms and making them a little less miserable.

"Both infections are caused by viruses and do not respond to antibiotics," Dr. Septimus says.

Rest is your best bet for a speedy recovery, according to the Mayo Clinic. Stay home, take a break from exercising and get as much extra sleep as you can. Staying hydrated is also a must, but if you can't stomach cold water, sip on juice, clear broth or warm water with honey and lemon.

"Maintaining fluid intake is very important to prevent dehydration," Dr. Cutler says.

If you have a fever or feel achy, OTC meds like ibuprofen or acetaminophen can help bring your temperature down and make you feel more comfortable overall, Dr. Septimus notes.

A sinus rinse or Neti pot can ease nasal congestion and sinus pressure, while cough suppressants containing dextromethorphan can help with coughing, he says. And if you're dealing with a scratchy throat, try gargling warm water mixed with a quarter to half teaspoon salt, per the Mayo Clinic.

What About Tamiflu?

As for antiviral meds like Tamiflu? It's a good option if you're at high risk for flu-related complications, but might not be worth it if you're otherwise healthy.

Tamiflu can make your symptoms a little less severe and help you get better a little faster if you start taking it within two days of getting sick, according to the CDC. But there's a cost: The meds can cause serious stomach pain, nausea and vomiting, as well as headache and fatigue, per the Food and Drug Administration.

"Antivirals are of limited value in otherwise healthy patients. They shorten the duration of symptoms by a matter of hours," Dr. Septimus says.

Dr. Cutler agrees, noting that options like Tamiflu are best reserved for people who are more likely to get seriously sick from the flu.

"Since nearly all flu cases will resolve without complication and Tamiflu can cause serious side effects, the limited benefits must be weighed against the known risks before taking it," he says.

Getting Better: When Am I Not Contagious?

Both colds and the flu usually clear up within a week or two. And you'll know that the virus is on its way out simply by how you feel.

Still, it's worth going easy on yourself until you're fully recovered and minimizing contact with others until you're no longer at risk for spreading germs.

"We know that those with the most severe symptoms of cough and fever are the most contagious," Dr. Cutler says.

On the other hand, once you're feeling better and your fever has cleared for at least 24 hours, you're no longer likely to be contagious, he notes.

That might all sound good in theory. But what if you're dealing with the tail end of a cold that just won't go away — should you stay home just because you have a mildly stuffy nose?

There's no right or wrong answer, especially in the age of COVID-19 (more on that in a minute). But if you do need to be out and about before your cold symptoms have fully subsided, stick with good hygiene practices. Wash your hands, be even more vigilant about wearing your mask and maintain some social distancing, both Dr. Septimus and Dr. Cutler suggest.

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Cold vs. Flu in the Age of COVID-19

Once upon a time, most of us tended to look at colds and the flu a little differently. While a fever or a hacking cough were cause to stay away from others, minor issues like a stuffy nose or scratchy throat probably wouldn't have stopped you from popping out to the grocery store or even going to work.

That's all changed, now that even mild symptoms could also be signs of COVID-19. It can be hard to tell the flu from COVID-19 based on symptoms alone, the CDC notes. And many health care providers are recommending COVID testing if a person has ​any​ symptoms. "I'm testing all patients with cold symptoms for COVID-19," Dr. Septimus says.

In short: If you think you have a bug but aren't sure what it is — even if your symptoms are minor — stay home and check in with your doctor. Together, you can decide whether you should get tested and how to figure out when you're no longer at risk for getting others sick.

"In patients with a negative COVID-19 test, in the absence of specific COVID-19 symptoms like a loss of taste and smell, if folks have cold symptoms, it's reasonable to go out with masking, hand hygiene and social distancing," Dr. Septimus says.

Is This an Emergency?

If you are experiencing serious medical symptoms, please see the National Library of Medicine’s list of signs you need emergency medical attention or call 911. If you think you may have COVID-19, use the CDC’s Coronavirus Self-Checker before leaving the house.
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