Should you be concerned about a particularly bad strain of bird flu - H5N1? WebMD went to public health experts to get answers to your questions about how it is spread, its symptoms, and how to prevent it.
Influenza (flu) usually comes on suddenly. In many cases you can pinpoint the hour when symptoms started. Symptoms develop 1 to 4 days after you are infected. Classic flu involves fever for about 3 days, followed by a gradual decrease in other symptoms.