Influenza (flu) is a respiratory illness that is contagious and caused by influenza viruses. Flu season can vary and may start as early as October and continue through as late as May. However, we usually see it peak between December and February. Certain groups of people are at high risk for serious complications of the flu, including older people, young children and people that have certain health conditions. Each year there is an immunization for influenza (flu) that helps to prevent infection. Click on the link below for an easy to read chart that outlines the difference between a common cold and the flu. If you would like more information on influenza (flu), you may also find the information provided by the CDC helpful; just click on the link below.