Cold and flu season is in full swing as four major respiratory viruses circulate the country. According to the Centers for Disease Control and Prevention, at least 15 states have "very high ...

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

Schools in at least two states canceled classes at the start of this week amid a surge in influenza cases nationwide.

For a second time this season, at least 41 states are reporting high or very high levels of the flu. Here's how to stay safe.

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