Nigerians have faced an unusual increase in denied entry into the U.S., with unexplained cancellations of their visas without ...

A new study suggests the underlying reason for these unexplained, or cryptogenic, strokes could hinge in part on whether someone has a type of hole between the upper chambers of the heart.

SEATTLE — Troubling new signs of how the coronavirus is spreading in the United States emerged Friday, as cases not explained by overseas travel or contact with a person known to be infected ...

The number of new unexplained pediatric hepatitis cases has swelled to more than 600 worldwide, the European Centre for Disease Prevention and Control said this week.

Authorities are looking for two drivers who might have witnessed what led to a deadly motorcycle crash in East El Paso back ...

Along with anchoring the Third Hour of TODAY, Dylan also hosts the NBC wildlife documentary series Earth Odyssey With Dylan ...

A new study suggests the underlying reason for these unexplained, or cryptogenic, strokes could hinge in part on whether someone has a type of hole between the upper chambers of the heart.