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Cold vs Flu – How to Know the Difference

 |  General

Even though the symptoms may be similar, there are several differences to be aware of to determine the difference between a cold and the flu. These sicknesses are caused by different viruses which affect the body in different ways. In general, cold symptoms are usually much milder than the flu.

Additionally, the cold virus usually does not lead to serious complications unless the patient has secondary health issues that put them at a higher risk for complications. However, the flu virus is responsible for many hospitalizations from complications such as pneumonia. Symptoms alone usually are not enough tell the difference between a cold and the flu. The only way to tell is to get tested.

Symptoms of the common cold

Symptoms of a cold usually set in gradually, appearing within one to three days after exposure to one of the common cold viruses, also known as rhinoviruses. The cold viruses attack your upper respiratory tract and can include the following symptoms:

Sore Throat

A sore throat is very common with a cold. The soreness can be soothed by lozenges, warm salt water gargles, and other homeopathic remedies. While redness may appear, the irritation is usually mild.

Runny Nose

A runny or stuffy nose and sneezing are common with a cold as it works its way through your sinuses. The discharge from your nose may become thicker and change colors such as yellow or green. However, this isn’t necessarily an indication that there is a bacterial infection.


You may develop a cough the produces phlegm or sputum. It can range in color such as clear, yellowish, or greenish. This is usually not a cause for concern unless you notice changes in the phlegm such as red streaks, which may indicate blood caused by inflammation.

Slight Fever

A slight fever can occur with a common cold as your body fights off the virus. Usually, though, it will not intensify. The cause for concern comes if your fever rises sharply or is accompanied by severe chills.

Symptoms of the flu

Flu symptoms are much more intense than the common cold. There are many different strains of Influenza, and like the common cold, it is a virus that attacks your upper respiratory system. Symptoms of the flu usually set in quickly, like you’ve been hit with a ton of bricks. Symptoms may include:

Sore Throat

While a sore throat does sometimes occur with the flu, it is far more common with a cold. If you do experience a sore throat, it may be a secondary infection such as strep throat.


Having a fever is a telltale sign of the flu, is usually above 100 degrees Fahrenheit, and can last for several days. A high fever could lead to chills, fever sweating, or hallucinations in more severe cases.


Headaches and extreme fatigue are very common with the flu. Especially if you are experiencing a fever as your body heats up to fight the virus.

Muscle Aches

As with the headache, muscle aches are extremely common. Chills cause your muscles to spasm which could lead to aches and pains.


Significant congestion of your nasal passages is due to the swelling and inflammation caused by the virus. Because everything in your respiratory tract is connected, this inflammation can spread.


A dry cough is the most type of cough associated with influenza. However, if you begin suffering from significant congestion in your lungs, it could be a sign of pneumonia or another serious complication.

At denova Collaborative Healthcare, we provide you with the knowledge and tools you need to keep your family healthy and strong through the cold and flu season. If you have concerns about how to tell the difference between a cold and the flu, reach out to us to schedule an appointment with one of our top physicians.