iStock/Thinkstock(NEW YORK) -- The flu season is in full effect, with more than triple number of states reporting high influenza-like illness compared to last week.
Twenty states reported high rates of the flu, according to the Centers for Disease Control and Prevention, up from just six states in the week of Dec. 15. Most people are seeking outpatient treatment for flu-like symptoms.
Young children up to four years old have the highest rate of hospitalization. An additional two pediatric deaths were reported by the CDC this week, bringing the total to six. The elderly, adults 65 years and older are the second group most susceptible to the illness.
The activity started in the Southeast and spread to the Southwest, said ABC Chief Health and Medical Editor Dr. Richard Besser. It continues to spread to the south central region of the U.S. and to states in the Central Plains.
The current strain sweeping the country is primarily the same strain that was passed around in 2009 during the swine flu pandemic.
"This strain of flu is covered in all of the vaccines that are currently available," Besser said. "Flu viruses do spread during the winter, for a variety of reasons. It's not too late to get protected. The sooner you get vaccinated, the longer you will have protection."
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