“They’re just showing up and dying.” Those six words made emergency responders’ ears perk up in Huntington, W.Va., when they buzzed over the radio. An official was quoting a caller who needed help at a local home. “I just caught a bit of that,” another official replied. “What are people showing up and doing?”

“All they can tell us is that ‘people are showing up and dying,’” the first official said. “We’re not sure what’s going on.” It was Monday afternoon, and an unusual mass crisis was beginning to unfold in Huntington, a city of nearly 50,000 on the western edge of West Virginia — a crisis increasingly familiar to paramedics, firefighters and police officers across the United States. CONTINUE