The flu is widespread in 30 states and has claimed almost 2,000 deaths this season, including 19 children, according to the Centers of Disease Control and Prevention.

Nearly every state reports elevated activity, the CDC said in its weekly update Friday.

The CDC estimated there have been at least 3.7 million flu cases so far this season, 32,000 requiring hospitalization. It reported 1,900 deaths, including 19 children.

Most patients are infected with a strain called B/Victoria that normally doesn't appear until the end of flu season. The virus tends to strike children and young adults more often, but that anyone can be affected, according to the CDC. 

The weekly reports finds widespread flu in Puerto Rico and 30 states: Alabama, Alaska, Arizona, California, Connecticut, Delaware, Florida, Georgia, Idaho, Indiana, Kentucky, Louisiana, Maryland, Massachusetts, Minnesota, Mississippi, Montana, Nebraska, Nevada, New Mexico, New York, North Carolina, Ohio, Oregon, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, and Washington.

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