Is It a Cold or Flu? Understanding the Difference Between These 2 Illnesses

Each year, millions of Americans succumb to a cold or flu infection. As respiratory infections, they share many of the same symptoms. If you catch a cold or the flu, you may experience a runny nose, coughing, malaise and headache. Colds aren't the same as a flu, however. They are two different ailments that affect the body in different ways. What's the difference between a cold and flu infection exactly?

Infection Rates

In terms of infection rates, colds are far more common than the flu. According to the Centers for Disease Control and Prevention (CDC), Americans catch a collective total of 1 billion cold infections per year. That means up to 20% of the general population will catch a cold infection in any given year. The flu is still relatively common, but it has much lower infection rates than that of colds.

Fever

Although they share similar symptoms, cold and flu infections don't have the exact same symptoms. If you catch the flu, you may experience a fever. Cold infections, on the other hand, typically don't cause a fever. You'll feel achy and tired with either of these infections, but flu infections are often accompanied with a fever in excess of 100 degrees Fahrenheit. If you don't have a fever, you may have a cold infection and not the flu.

Duration

Another difference between cold and flu infections is their duration. Cold infections are typically shorter than flu infection. A cold infection may clear up in three in seven days, whereas a flu infection can take up to two weeks to recover from. The long duration of flu infections means you'll feel sick for a longer period.

Onset

It's also worth noting that flu infections have a faster onset than cold infections. A flu infection can seemingly come out nowhere. You may feel fine one day, only to wake up the following morning with severe symptoms. Cold infections have a longer onset. The symptoms of a cold infection usually emerge gradually over a period of several days.

Vaccination

Vaccines are available to lower the risk of flu infections. Each year, a new vaccine is released to protect against the current strain of the flu virus. Cold infections are caused by viruses as well, but unfortunately there isn't a vaccine available to protect against them. There are over 200 viruses known to cause cold infections, and many of these viruses change or mutate. Therefore, it's nearly impossible for medical experts to create an effective cold vaccine.