The flu is a respiratory (i.e., nose, throat and lung) infection that can be caused by a variety of influenza viruses. Many people use the word "flu" when they actually have a cold. Although the common cold is also caused by viruses, the flu and common cold differ in several ways.

It's important to recognize the difference, not just because they require different treatment but because a flu can be a much greater health concern because it has the potential to lead to serious complications. Can you tell the difference? Test your knowledge!

  Is it more likely to be
  If you have... Cold? Flu? Either?
1 fever (over 102°F or 38°C)
2
  severe
  mild to moderate
3
  severe
  mild to moderate
4 extreme exhaustion
5 stuffy nose
6 sore throat
7 sneezing
8
  severe
  mild to moderate
9 rapid onset
(less than a day from fine to miserable)
10 gradual onset
(coming on for a day or two or more)
11 decreased appetite