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

Eleven states are experiencing very high levels of flu and some schools have been closed by the burden on students and staff.

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

The U.S. winter virus season is in full force, and by one measure is the most intense in 15 years.

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.

(NEXSTAR) – The map of flu activity across the United States continues to darken, both figuratively and literally, as case ...

The Centers for Disease Control and Prevention resumed publishing its weekly scientific report Thursday after an unprecedented pause, but information about the bird flu virus that was supposed to ...

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