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COVID-19 or Flu? How to Tell

COVID-19 and the flu have similar symptoms. The two can be hard to tell apart. The only way to know for sure which illness you have is to be tested.

If you have COVID-19 or the flu, take precautions to prevent spreading the virus to other people. This means staying home and limiting contact with people in your home. You'll need to wash your hands often and disinfect surfaces that you touch. And be sure to wear a mask when you're around other people.

COVID-19 and the flu have these symptoms in common:

  • Fever or chills
  • Cough
  • Shortness of breath
  • Fatigue (tiredness)
  • Sore throat
  • Runny or stuffy nose
  • Muscle and body aches
  • Headache
  • Vomiting and diarrhea (more common in children than adults)

COVID-19 has another symptom that also may occur:

  • New loss of taste or smell

COVID-19 symptoms may appear from 2 to 14 days after infection.

Flu symptoms usually appear 1 to 4 days after infection.

The importance getting of a flu shot during COVID

It's important to stay up-to-date on your flu and COVID-19 vaccines. Talk to your doctor about what is best for you.

The flu and COVID-19 can be active at the same time. You can get sick with both infections at once. And having both may make you more sick than getting just one infection.

Getting both vaccines can protect you and others from getting very sick. If you do get the flu or COVID-19 after being vaccinated, you're much less likely to get seriously ill.

It's especially important for those at high risk for problems from flu or COVID-19 to stay up-to-date. This includes young children, older adults, people who are pregnant, and people who have long-term health problems or a weak immune system.

Credits

Current as of: February 27, 2026

Author: WebMD Ignite Staff
Clinical Review Board
All WebMD Ignite education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Current as of: February 27, 2026

Author: WebMD Ignite Staff

Clinical Review Board
All WebMD Ignite education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.