When those nasty symptoms set in, they might signal the flu—or something else entirely. Here’s how to tell the difference.

It’s the sick season

Black woman feeling sick and seasonal flu symptomstommaso79/Shutterstock

Flu season is here, triggering memories of the last year’s severe season. Especially for vulnerable people like children, the elderly, and those with lung ailments such as asthma and cystic fibrosis, classic flu symptoms including a sudden fever, muscle aches, fatigue, and a dry cough can be cause for worry. But not every flu-like symptom signals the flu. Many other illnesses can prompt the same symptoms, says Sean Cloonan, MD, an internist and infectious disease specialist at Scarsdale Medical Group. Here’s a rundown of seven copycat conditions that could make you think you have the flu.

Cold

Sick african american girl working from home office. Ill young black woman with cold, sitting at desk with laptop computer and sneezing for allergy.Diego Cervo/Shutterstock

The common cold can also bring on a cough and fatigue, but it’s caused by different viruses from those that bring on flu, says Dr. Cloonan. The flu tends to be more intense than a cold, according to the Centers for Disease Control and Prevention (CDC)—though a cold typically lasts longer (seven to ten days versus three to five days for the flu); you’ll also get a stuffy or runny nose as well. These are the textbook scenarios, says Dr. Cloonan, “but real life doesn’t always follow a textbook, and someone who seems to have a cold can actually be fighting off influenza.” The only way to definitively tell the difference is to be tested for the flu. Don’t miss these 50 ways to avoid catching a cold this season.

Strep throat

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You’ll also get a fever and a general feeling of malaise with strep, says Dr. Cloonan. But the intense pain in your throat along with redness and, sometimes, white spots on your tonsils distinguish this infection from the flu. “Many viruses that cause the common cold can cause strep throat as well,” says Dr. Cloonan. If you think you may have strep throat, see your doctor for testing and, if it’s positive, a prescription for antibiotics. Check out these strep throat symptoms you should never ignore.