Cold, the Flu or COVID-19: How to Tell the Difference and When to See a Doctor
September 12, 2025 | Tags:
You have the sniffles. Now a cough. And – oh great – a headache, too.
How can you tell if your sniffles and cough are the effects of a cold, the flu or COVID-19? We’re in prime season for all three. Dr. Dwight McFadden, Assistant Medical Director at Medical Mutual, talks about the differences and similarities, and when you should see a doctor.
Key differences
The viruses that cause all three illnesses can be transmitted from person to person through the air or on surfaces. While they have similar symptoms, the key to telling the illnesses apart is how quickly the symptoms present themselves:
- Common Cold: Symptoms typically develop gradually and include sneezing, runny or stuffy nose, cough and a sore throat.
- Flu: It is often an abrupt onset with high fever, body aches, headache, chills and a cough.
- COVID-19: Symptoms vary, with some people experiencing fever, headache, chills and body aches, and others presenting with upper respiratory symptoms such as a cough, runny nose and sore throat. Some people even have diarrhea.
“The key differences are in the severity, the prevention and the treatment, as well as the virus that causes each illness,” Dr. McFadden said. “The flu and COVID-19 are generally much more serious than a cold.”
When you should see a doctor
People with high-risk factors – such as cardiac or pulmonary disease, or those who are immunocompromised – should see a doctor immediately, especially if symptoms are severe, Dr. McFadden said.
If you experience concerning symptoms, such as shortness of breath, chest pain, loss of consciousness, confusion or high fever that does not respond to medications, you should seek care regardless of your risk factors. If you are unsure of your symptoms, you can call our Nurse Line 24/7 at 1-888-912-0636 (TTY 711 for hearing impaired).*
“If you have any questions, you should always contact your primary care provider or speak with a nurse,” said Dr. McFadden. “They can usually address these illnesses.”
Early detection is key to starting antivirals, like Tamiflu, which can reduce the severity and duration of the flu.
“As we age, the risk of severe complications from the flu are reduced by taking an antiviral,” Dr. McFadden said.
COVID-19 treatment is evolving, with antivirals and other approaches used in severe cases. There are no antiviral treatments for the common cold. Antibiotics will not treat a cold, the flu or COVID-19.
The power of prevention
To reduce the risk of contracting or spreading these illnesses, preventive measures – handwashing, covering coughs and sneezes, and staying home when you are sick – are crucial.
“We cannot overemphasize the importance of some of the simple things that your parents or your teachers told you to do, like covering your cough or sneeze,” Dr. McFadden said.
Vaccines are available for viruses like the flu and offer effective protection against infection. Age is a factor in how these illnesses affect individuals as older adults, especially those over 65, are at higher risk for severe complications from viruses like the flu and COVID-19. Vaccination is highly recommended for this age group by organizations like the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO).
Resources available to you as a Medical Mutual member
It is important to have a primary care provider (PCP) who understands your medical history. If you do not have a PCP, Medical Mutual can help. Members can use the Find a Provider search tool by logging in to the My Health Plan portal or call the Customer Care number on your member ID card.
The CDC, WHO and American Academy of Pediatrics publish immunization schedules for children, adolescents and adults. Medical Mutual recognizes that healthcare decisions are important and personal. Talk to your PCP regarding vaccine recommendations and what’s right for you.