If you have sniffles, sneezes, coughing or sore throat, it can be hard to tell if your symptoms are from allergies, a cold or the flu. And now there’s another possibility: COVID-19.

Until you know for sure what’s causing your symptoms, it’s always good to err on the side of safety and stay home and away from others.

Concern about catching the COVID-19 virus has made everyone more tuned in to the people around them, especially if they’re showing any signs of sickness. They may be more worried than usual about a cough or sneeze, even if you think it may just be sinus or allergy troubles.

So how can you tell what you have?

Stay Alert

Take a close look at your symptoms. A cough alone may not be cause for concern, but if you get a fever or have trouble breathing, call your doctor right away.

The signs of COVID-19 include fever, dry cough and shortness of breath, says the Centers for Disease Control and Prevention (CDC).  You may also have other symptoms that you get when you have a cold or the flu, such as congestion, feeling tired and upset stomach.

If your symptoms are mild, you may get better on your own. In that case, you may not need to be tested for COVID-19. But it is still important that you not go around others until you are well.

Colds and Allergies

When you don’t feel well, you might wonder whether it’s a cold or allergies. They share some similar symptoms like coughing, sneezing, and runny or stuffy nose. So how can you tell the difference?

How long your problems last is one of the big clues. Colds don’t often stick around more than two weeks. Allergy symptoms can linger much longer.

Colds are caused when a virus gets into your body and makes you sick. Your immune system launches a defense against germs. Your body fighting off the cold is what causes symptoms like a stuffy nose or cough. Unlike allergies, colds can also make your body ache.

Allergies are caused by an overactive immune system. Your body overreacts to harmless things like pollen or dust and works to protect you from them. That can cause coughing, sneezing and stuffy nose, like colds. Unlike colds, allergies often cause watery, itchy eyes.

Also keep in mind that colds are contagious, while allergies are not. 

Flu

While flu shares some symptoms with colds or allergies, it is more severe and causes more serious symptoms. It also tends to come on much quicker and more severely. The American Lung Association says to watch for these signs of flu:

• Sudden, high fever
• Headache, muscle and joint aches and pain
• Dry cough
• Sore throat
• Chills
• Nasal congestion
• Runny nose
• Fatigue
• Stomach symptoms like nausea, vomiting or diarrhea (more common in children)

Get Your Flu Shot

Like colds, flu is contagious and is caused by a virus. Unlike colds, you can get a vaccination to help protect yourself and others from flu.

The CDC says most people who are six months or older should get a yearly flu shot. It takes about two weeks after vaccination for the shot to protect against flu virus infection. So don’t wait until peak flu season to get your shot. Get it as soon as it is available. Your health plan may cover a flu shot at no cost to you when you go to your primary care doctor or use an in-network provider or pharmacy.

Avoid Germs

To stay healthy, protect yourself from germs of all kinds:

• Wash your hands often with soap and water for at least 20 seconds.
• Use hand sanitizer often throughout the day.
• Try not to touch surfaces used by a lot of people, like door handles, light switches, phones, keyboards and flat surfaces. Disinfect those surfaces around your home or office often.
• Keep your hands away from your eyes, nose, and mouth, especially when you’re away from home.
• When you’re out in public, try to stay 6 to 10 feet away from other people.

Sources: Symptoms of COVID-19,  Centers for Disease Control and Prevention (CDC), 2022; Who Needs a Flu Vaccine and When,  CDC, 2021; Is it a Common Cold or Allergies,  WedMD, 2021; Flu Symptoms, Causes, and Risk Factors,  American Lung Association, 2020; Runny Nose,  Cleveland Clinic, 2021

Originally published 9/2/2021; Revised 2022, 2023