In U.S., Peak Flu Season This Year Was Worse Than Last

http://www.gallup.com/poll/147449/Peak-Flu-Season-Year-Worse-Last.aspx

Residents of cold weather climates are probably more susceptible to getting sick with the flu as they spend more time indoors in the winter, increasing their opportunity to catch the virus. Cooler weather also creates more favorable conditions for the virus to survive in nature, which also increases the chances that someone will actually get sick. These factors likely play a role in increasing reports of the cold and flu in the winter months, and why warmer weather states tend to have lower rates of colds and the flu than their colder weather counterparts.