How to differentiate between cold, flu, allergy, and virus symptoms

Feeling under the weather? Use this guide to common symptoms to get the facts and figure out your next steps.
Published March 6, 2020

These days it seems that every sniffle and sneeze has people Googling their symptoms faster than you can say achoo! So how can you determine whether you’re dealing with a regular old cold or something scarier? First step, don’t panic. Next, use this guide featuring tips from Dr. Neil Schachter, M.D., medical director of the Respiratory Care Department of Mount Sinai Medical Center in New York City and author of The Good Doctor’s Guide to Colds & Flu, to zero in on your symptoms and take a stab at what’s going on. (Pro tip: It's always safer to consult a doctor than attempt a self-diagnosis.)

Your symptoms: A runny nose, headache, and sore throat

You may have: A cold 

The symptoms of the common cold are mostly “neck up.” You may also experience sneezing, coughing, post-nasal drip, and watery eyes. Pleasant? Not at all, but the virus is usually short-lived. However, if your cold lasts longer than a week or your symptoms are severe, see your physician. You might have strep throat (which can require antibiotics), or your cold may have turned into a sinus infection. 

How to treat a cold:

A painkiller that contains acetaminophen or ibuprofen can ease your headache, a salt-water gargle can soothe a sore throat, and an OTC decongestant will help clear congestion. Still stuffed up? Try a saline nose spray. 

Med-free remedies can also give your recovery a boost. Getting adequate rest, drinking plenty of fluids, using a humidifier or cool-mist vaporizer, and breathing in steam from a hot shower can all help you feel better while you beat your cold. What you should definitely skip: antibiotics. They’re ineffective against the cold virus.

How to avoid getting a cold:

Wash your hands regularly and thoroughly (for at least 20 seconds—count it out in your head) and avoid touching your face. It’s also smart to avoid close contact with people who are sick.

Your symptoms: Body aches, chills, and a chest cough

You may have: The flu

Unlike a cold, flu symptoms can affect you below the neck, too. “Plus, if you come down with the flu, you may also have a high fever (over 101 degrees Fahrenheit) and feel extremely fatigued,” Dr. Schachter says.

How to treat the flu:

Since the neck-up symptoms for a cold and the flu are identical, the same over-the-counter remedies mentioned above—including bed rest and plenty of fluids—can soothe a headache, congestion, and more. While the Centers for Disease Control and Prevention (CDC) says that most people won’t need antiviral drugs, if you’re extremely sick or in a high-risk group (such as those with asthma, diabetes, or heart disease), your doctor may prescribe an antiviral medication, like Tamiflu or Relenza. These can shorten the duration of the illness and reduce the risk of complications, but know that they work best if started within a couple days of getting sick.

If you have flu-like symptoms, keep your germs to yourself by staying at home. The CDC recommends that you don’t go out in public until at least 24 hours after your fever has eased up. 

How to avoid getting the flu:

Your first line of defense is the influenza vaccine: The jab can reduce the risk of getting the flu by up to 60%, according to the CDC. You should also take the same precautions associated with avoiding the common cold, such as washing your hands often and keeping your distance from those who are ill. 

Your symptoms: Itching of the nose and eyes, sneezing, and a runny, stuffy nose

You may have: Allergic rhinitis, aka hay fever or seasonal allergies

It’s easy to confuse hay fever for the common cold, but one key difference is how suddenly symptoms hit. Allergies seem to come out of nowhere (hello, pollen!), but a cold builds slowly, taking a day or two to develop. Itchiness is also an indicator that you’re dealing with allergies, not a cold.

How to treat seasonal allergies:

Prescription nasal sprays target in-the-nose inflammation, helping to treat a runny, itchy nose. If that doesn’t do the trick you can add an antihistamine (like Claritin or Allegra), which work best when you start using them before you first come into contact with seasonal allergens, so plan to dose up a few weeks before you typically start sniffling. Once symptoms kick in, you can also use over-the-counter decongestant medications to alleviate discomfort.

Sick and tired of dealing with hay fever every spring? Consider immunotherapy, also known as allergy shots, which gradually exposes your immune system to small doses of allergens to build tolerance. Some people can experience complete relief from seasonal allergies after completing a full course of allergy shots, according to the American Academy of Allergy Asthma & Immunology. Not a fan of needles? You’re in luck. Under-the-tongue allergy tablets are now available for certain allergens—just ask your doctor.

How to avoid seasonal allergies:

Unless you’ve completed immunotherapy treatment, you may not be able to dodge hay fever completely, but limiting your exposure to pollen can ease the severity of your symptoms. The pollen count is higher on dry, windy days, so avoid being outdoors as much as possible when the forecast is breezy. 

Additionally, keep windows and doors closed during allergy season, and avoid tracking pollen indoors by changing out of your outdoor clothes and shoes soon after entering the house. It’s also a good idea to take a shower and wash your hair before bed so that you don’t breathe any allergens in throughout the night. 

Your symptoms: Fever, cough, and shortness of breath

You may have: COVID-19

COVID-19, the illness caused by a novel strain of coronavirus first detected in late 2019, has spread worldwide. Anyone infected with the virus can experience mild to severe symptoms, though older adults and people with serious underlying medical conditions such as heart disease, lung disease, and diabetes seem to be at a higher risk for serious complications and death, according to the CDC. It can take two to 14 days after exposure for symptoms of COVID-19 to show up. These may include:

  • Fever or chills
  • Cough
  • Shortness of breath or difficulty breathing
  • Fatigue
  • Muscle or body aches
  • Headache
  • New loss of taste or smell
  • Sore throat
  • Congestion or runny nose
  • Nausea or vomiting
  • Diarrhea

How to treat COVID-19:

Many people with COVID-19 experience mild illness and are able to recover at home, the CDC reports. If you think you may have been exposed to COVID-19, contact your healthcare provider to determine the best course of action. Because some symptoms of COVID-19 mirror those of the flu, discerning between the two illnesses may require testing. If at any point you experience severe symptoms of COVID-19—such as difficulty breathing—seek medical care immediately.

Because the virus spreads easily from person to person, the CDC recommends that patients isolate themselves at home until meeting several criteria indicating that their illness is no longer contagious. People who are sick with COVID-19 symptoms should also separate themselves from household members to whatever extent possible, and wear a face mask at times when close contact cannot be avoided.

While measures such as over-the-counter fever reducers may temporarily alleviate certain symptoms of the virus, as of October 2020 there is no treatment for COVID-19 specifically. The U.S. Food and Drug Administration (FDA) advises consumers to beware of fraudulent cures: “Products that claim to cure, mitigate, treat, diagnose or prevent disease, but are not proven safe and effective for those purposes, defraud consumers of money and can place consumers at risk for serious harm,” the agency’s website warns.

How to stop the spread of coronavirus:

As of late 2020, a vaccine for COVID-19 is not yet available. Therefore, preventing infection depends on avoiding exposure to the virus. The CDC offers these and other tips for stopping the spread of coronavirus:

  • Wash hands often with soap and water for at least 20 seconds, especially after leaving a public setting, before touching your face, and after coughing into a hand or blowing your nose. If soap and water aren’t available, use a hand sanitizer that contains at least 60% alcohol.
  • At all times, maintain 6 feet of distance between you and any people who are not living in your household.
  • Wear a mask that covers your nose and mouth whenever you are in a public setting (such as a store or gym) or near people who do not live in your household. People who are infected may not feel sick but still can spread the virus to others.
  • Disinfect frequently touched surfaces such as doorknobs and computer keyboards.
  • Monitor your health and speak with your doctor immediately if you develop symptoms of COVID-19. If you become sick, inform your close contacts that they may have been exposed to the virus.

Note: Public health recommendations concerning COVID-19 continue to evolve as researchers learn more about the virus and its effects. The information in this article might not reflect the latest guidelines. For up-to-date information on COVID-19, visit the CDC’s website.

Related links