The flu season arrived early in the U.S. this year, but health officials and experts say it's too early to say this will be a bad one.
Experts say evidence so far is pointing to a moderate flu season—it just looks worse because last year's season was so mild.
Flu usually doesn't blanket the country until late January or February. Now, it's already widespread in more than 40 states. That could change when the next government report comes out Friday.
There are a few factors complicating the situation. The main flu virus this year tends to make people sicker. And there are other bugs out there causing flu-like illnesses. So what some people are calling the flu may, in fact, be something else.
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