Five children have died from the flu in the U.S. this year. The Centers for Disease Control now says this year's flu strain is worse than most years.
The C.D.C say flu activity has increased since the start of November and is now higher than usual for this time of year. More than 550 people have been hospitalized nationwide because of the flu.
The report says that southern states like Georgia, Louisiana, and Oklahoma have reported the most widespread activity. The C.D.C. recommend everyone should get this year's flu vaccine.
But fewer than 50 percent of people have done so.