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WHAT CAUSES THE FLU?

Influenza, commonly known as the flu, is a viral respiratory infection caused by the influenza viruses. It can affect your entire respiratory system—nose, throat and lungs.1

The flu is very contagious and can spread easily. The viruses usually spread through droplets that travel through the air when someone with the flu coughs or sneezes. These droplets can be inhaled by anyone who happens to be nearby or can be picked up by touching a surface that has the germs, like a desk, door handle or keyboard—and then transferred by touching your mouth, eyes or nose.4

Because flu viruses change every year, researchers worldwide monitor the 3 or 4 strains that are most likely to infect the most people. The researchers then create a seasonal flu vaccine to best meet the needs of the current cold and flu season..2

Flu Symptoms

The flu can range from mild to severe—and symptoms usually develop quickly.4 In fact, one of the main differences between a cold and the flu is that the flu usually comes on fast. Even though a cold and the flu share a lot of the same symptoms, people with the flu will usually feel a lot worse.

Common flu symptoms include:

Fever*
Chills, cold sweats and shivers
Aching joints and limbs
Feeling tired, exhausted, fatigued
A cough
Sore throat
Runny or stuffy nose
Headache

How To Help Prevent The Flu

Getting an annual flu vaccine before the start of flu season is the first and most important step in protecting against the flu. Since these viruses constantly change, even if you’ve had the flu in the past, your body might be susceptible to a new strain on any given year.3 That’s why it’s important to get a flu vaccine every year—that way you’ll be best prepared for the most likely flu strains that will be going around during the year.

There are also some everyday steps you can take to help prevent coming into contact with—and spreading—the germs that cause the flu:3

  • Wash your hands often. Thorough hand-washing is an effective way to prevent many common infections.
  • Cover your coughs and sneezes. Cover your mouth and nose with a tissue when you sneeze or cough to help prevent spreading the virus.
  • Stay home and rest. If you're sick, stay home for at least 24 hours after your fever subsides so that you lessen your chance of infecting others.
  • Stay on top of the flu. Use our cold & flu tracker to get a thorough report of cold and flu incidences in your area—so you’re able to prepare and be ready.

If you come down with the flu, over-the-counter cold and flu medicines like Theraflu can help ease your most severe symptoms and get you back on your feet. And with powerful symptom relief, especially at night, you’ll be able to rest easier as you recover—and feel better.

*Not Everyone With The Flu Will Have A Fever