Do you have COVID-19? Or is it the flu, a cold, or allergies?

With the new COVID-19 variant Omicron, every throat tickle or headache might make you wonder if you're infected. This question can become even tougher to answer as we enter flu, allergy and cold season.  The symptoms for these illnesses may look very similar, so take a look at our guide below to distinguish between the illnesses.

And remember, if you're feeling sick, your most reliable test is a COVID-19 antigen or PCR test. 

Breaking it Down

A good way to tell if you have COVID-19 is to understand the differences in symptoms that these illnesses cause, as well as how they spread, how they are treated and how they can be prevented. Below is a break down of each.


COVID-19 is a highly contagious respiratory disease caused by an infection with the SARS-CoC-2 virus. COVID-19 usually spreads through close contact as respiratory droplets are released when someone talks, coughs, sneezes or even breathes. The range of COVID-19 symptoms is quite broad, especially with the introduction of new variants. Additionally, vaccinated people with breakthrough infections might also experience different symptoms than those who are unvaccinated. Symptoms could range from asymptomatic to severe pneumonia. The most common symptoms include fever, dry cough, shortness of breath, fatigue, body aches or loss of smell. 


Unlike COVID-19, seasonal allergies are not caused by a virus but rather an exposure to allergens, like pollen, that trigger an immune system response. Allergies are not contagious and generally, allergy symptoms can be treated with over-the-counter or prescription antihistamines, nasal sprays and decongestants. A common allergy symptom is itchy or watery eyes, which is not linked to the flu, a cold or COVID-19. Here are a few other ways to decipher between COVID-19 and allergies:
  • Unlike COVID-19, most people with allergies have a history of allergies.
  • Allergy symptoms tend to be more long-lasting than viral symptoms.
  • Itchiness is not a symptom of viral illness, but it is with allergies.
  • Allergan patients also do not develop a fever, while most COVID-19 patients do.

The Common Cold

Both COVID-19 and the common cold are caused by viruses, however the cold is most often caused by rhinoviruses. These viruses spread in similar ways and cause many of the same symptoms but there are a few key differences. Symptoms of a common cold usually appear 1-2 days after exposure to a cold-causing virus, while COVID-19 symptoms generally take anywhere between 2-14 days to develop after exposure. Additionally, fevers are a common COVID-19 symptom but are rarely linked to colds, and the same goes with other COVID-19 symptoms like fatigue, shortness of breath and diarrhea.

The Flu

The flu and COVID-19 are both contagious respiratory diseases caused viruses. COVID-19 is caused by SARS-CoV-2 while the flu is caused by influenza A and B viruses. Both diseases have similar symptoms, ranging from asymptomatic to mild or severe symptoms. Because of these similarities, it can be very hard to distinguish between the two based on symptoms alone, so testing is strongly recommended. You can also have both COVID-19 and the flu at the same time. One of the only major differences between the two diseases is that flu symptoms generally appear much soon after exposure, close to 1-4 days, compared to COVID-19's 2-14 days. 


Taking a Closer Look

Use this chart for a more in depth look the different symptoms.

Body Aches Rarely
Chills No No
Fever No Rarely
Headache Sometimes Sometimes Sometimes
Nasal Congestion Sometimes Sometimes
Runny Nose Sometimes Rarely
Sneezing Sometimes Rarely
Itchy/Watery Eyes No No No
Dry Cough Sometimes
Shortness of Breath Sometimes Sometimes Sometimes
Wheezing Sometimes Sometimes Sometimes Sometimes
Loss of Smell Mild Rarely Rarely
Sore Throat Sometimes Sometimes
Nausea, Vomiting, Diarrhea No Sometimes Sometimes Sometimes

Source: Emerson Hospital

Get Tested

As of now, the only true way to know if you have COVID-19 is to get tested. A good rule of thumb is when in doubt, get tested to protect yourself and others. Also, while you can't get a vaccine to prevent the common cold or allergies, you can get vaccinated against COVID-19, which greatly reduces the risk of infection and serious illness and hospitalization if you do happen to get infected.