(CNN) – Flu season is picking up months ahead of schedule with a mutated virus spreading in some parts of the United States, surprising some people who might not even be thinking about their annual flu shots yet.

This year, the season started 2 1/2 months earlier than what’s typicaland hit states on the West Coast first, which is unusual, said Dr. Alex Greninger, head of the Division of Infectious Disease Diagnostics at the University of Washington’s Department of Laboratory Medicine. (Read More)