A contagious new COVID-19 variant called NB.1.8.1, aka "Nimbus," is now dominant in the United States, CDC data show. What to know about symptoms and vaccines.

Aim To examine symptoms indicative of respiratory tract and gastrointestinal infections and determine risk factors for such symptoms in elite cross-country skiers. Methods Self-reported training and ...

Australian YouTuber Spanian was rescued by helicopter after experiencing extreme altitude sickness during a spontaneous trip ...

The father of Zane Wach, 14, says hallucinations prompted his son to question whether he was dreaming before he fell from a ...

Altitude sickness is a serious condition for hikers. But what if it's not altitude sickness? This deadly condition with ...

A devastating hiking accident on Mount Whitney has left a 14-year-old California boy clinging to life after altitude-induced ...