How to Determine if it's COVID-19, the Flu or Common Cold

Posted January 03, 2023 by Munshi Moyenuddin, MD

It’s that time of year again. You just woke up with a fever, sore throat and cough. Could it be COVID-19? The flu? Maybe just the common cold?

Different viruses that infect the respiratory tract can cause any of these illnesses. All of them are contagious and share similar symptoms, which can make it difficult to distinguish between COVID-19, the flu and common cold.

COVID-19 is a contagious respiratory disease caused by infection from the SARS-CoV-2 virus. The flu is caused by an infection by any of the different strains of the influenza A and B viruses, whereas the common cold is most often caused by an infection by rhinoviruses.

All of these viruses spread in similar ways, mainly through respiratory droplets released when someone talks, coughs, sneezes or even breathes. These droplets can be inhaled or land in the nose or mouth of another person.

Being aware of each virus’ symptoms and understanding their key differences is important to getting to the bottom of what’s causing you discomfort, receiving the right treatment and slowing the spread this season. 

Compare symptoms of COVID-19, the flu and common cold

A key difference is COVID-19 has a unique symptom associated with it: changes in or complete loss of taste and smell. In addition, COVID-19 typically produces a dry cough. Compared to the flu, COVID-19 can cause more serious complications in some people.

Sneezing is usually more associated with the common cold than with the flu or COVID-19. In addition, a person with a cold rarely experiences muscle aches, and a cold never causes vomiting or diarrhea.

Another important differentiator between these viruses is the onset. COVID-19 symptoms usually begin about two to 14 days after exposure, while flu symptoms typically appear one to four days after exposure. Common cold symptoms occur one to three days after exposure.

Because these viruses share many of the same symptoms, it can be difficult to distinguish based on symptoms alone. Testing may be necessary to confirm a diagnosis.

Prevention is best

Prevention is the best medicine to protect yourself from these viruses. This winter, practice healthy habits to avoid many sick days for you and your family, including:

• Get vaccinated against the flu and COVID-19.
• Wash your hands regularly with soap and water. If a sink isn’t available, use an alcohol-based hand sanitizer.
• Practice social distancing and avoid close contact with anyone who is sick.
• Cover coughs and sneezes with a tissue or the inside of your elbow.
• Avoid touching your eyes, nose and mouth.
• Clean and disinfect frequently touched surfaces in your home, especially if someone is ill.
• Keep your immune system strong by getting plenty of rest, exercising regularly and eating a balanced diet.

If you’re sick, stay home and talk to your doctor to see if testing is necessary. Seek immediate medical attention if you’re having trouble breathing, persistent pain in the chest or confusion.