Influenza levels in the US are the highest they've been in 15 years amid winter weather and a second wave of the virus.

Flu infections are at or near their highest levels in at least 15 years and are still rising, the Centers for Disease Control and Prevention says.

The map of flu activity across the United States continues to darken, both figuratively and literally, as case numbers spike ...

Levels of influenza nationwide are now at the highest they have been since the peak of the 2009 swine flu pandemic, according ...

More than 24 million people have had seasonal flu this season, according to estimates from the Centers for Disease Control ...

The U.S. influenza rate is at or near its highest level in at least 15 years and is still on the rise, the U.S. Centers for ...

Outpatient health care visits for flu-like illnesses are at their highest levels in 15 years, according to data updated ...