Lacking connection can increase the risk for premature death to levels comparable to smoking 15 cigarettes a day, according to a new advisory from the U.S. Surgeon General.

Nodding syndrome is a rare neurological condition that can result in head nodding and violent seizures. Some researchers think they know the cause, but questions remain.

The Department of Justice announced arrests in an international operation targeting fentanyl sales on the dark web that spanned the U.S., Europe and South America. Nearly 300 people were arrested.

Voter turnout for last year's elections was the second highest for a midterms since 2000, and close to half of voters cast ballots early or by mail, estimates from a Census Bureau survey show.