Sniffles, sore throat, fever, and aches and pains may accompany a number of illnesses, but during the wintertime such symptoms are typically indicative of influenza.

Throughout much of North America, flu season peaks between December and February. But flu season can occur anywhere from October to March, advises the U.S. Centers for Disease Control and Prevention. The flu is contagious and can sideline people for extended periods of time. The CDC says that each year one in five Americans gets the flu.