Find care now
If you are experiencing a medical emergency, please call 911 or seek care at an emergency room.
The cold, flu, and COVID-19 are all contagious viruses that can be spread through the air. And, because they share many of the same symptoms, it can be hard to tell which one you have when you’re sick.
As we head deeper into the winter months, many people may be wondering, what’s the difference? How can I tell what I have when I’m sick?
Here’s how to determine which you might have and when to seek medical care.
Learn about our primary care and urgent care options:
The cold, flu, and COVID-19 are caused by different viruses.
The cold is a result of over 200 viruses, including rhinovirus, or parainfluenza virus—which is different from the influenza virus.
The flu, on the other hand, is caused by two strains of the influenza virus, which can affect us more severely than a cold. Type A influenza is the most common cause of flu spreads from person to person. Type B influenza is less common but still spreads among humans. It’s dangerous but less severe than Type A.
The COVID-19 virus is entirely different compared to the influenza virus and viruses that cause colds. COVID-19 is an acronym created by the World Health Organization (WHO) to describe the virus, “coronavirus disease of 2019”, or the “severe acute respiratory syndrome coronavirus 2” (SARS-CoV-2). Several coronaviruses have affected the world in the past few decades. This includes MERS (Middle East Respiratory Syndrome) and SARS (Severe Acute Respiratory Syndrome). Every major disease outbreak is different, and it can be hard to know what to expect when it comes to severity and treatment.
Colds are generally milder than flu or COVID-19 symptoms.
Since many cold, flu, and COVID-19 symptoms are similar, it can be hard to distinguish which is the cause. It’s especially difficult to determine if you have the flu or COVID-19, as they’re the most similar. For some people, the flu and COVID-19 can cause moderate to severe symptoms, including:
- Cough
- Fever
- Shortness of breath
- Body aches
In general, cold symptoms tend to be milder than the flu and COVID-19. And, the length of time it takes for symptoms to appear can indicate which infection you have. For example, a runny nose and mild cough that worsens gradually may indicate a cold. But a sudden onset of fever, fatigue, and shortness of breath may be a sign of the flu or COVID-19. In other words, a cold may take a few days to sink in, whereas the flu or COVID-19 may seem to appear abruptly out of nowhere.
COVID-19 and the flu can both cause some gastrointestinal issues that aren’t typically present if you have a cold (or allergies). Similarly, a high fever is an uncommon cold symptom, whereas both COVID-19 and the flu can result in a persistent, high fever.
While COVID-19 and flu symptoms may look similar, there are differences that can help you know what you’re dealing with. Some people with COVID-19 report a loss of taste and smell, although not everyone does. In comparison, the cold or flu should not cause a loss of taste or smell. COVID-19 can also cause shortness of breath. However, the cold or flu does not commonly result in difficulty breathing, unless you have a preexisting condition affecting the lungs, such as asthma or chronic obstructive pulmonary disease (COPD).
There are also some people who get COVID-19 who report no symptoms, making them asymptomatic. If you do have cold, flu, or COVID-19 symptoms of any kind, it’s important to connect with your primary care provider early to rule out anything concerning.