Millions of people compulsively pick their skin or pull their hair. Social media is helping some of them to recover.

In the ruins of a health-care system, many medical facilities have become graveyards. Doctors continue to deliver lifesaving care—but they risk their own lives in the process.

If it weren’t for the viral social media posts or the pictures to remember what happened on a Scottsdale, Ariz. pitcher’s mound on Feb. 15, you wouldn’t think ...