Hundreds of thousands of bikers who attended the annual Sturgis Motorcycle Rally in western South Dakota have since left the area. But public health departments in multiple states are trying to measure how much and how quickly the coronavirus spread in the bars, tattoo shops and gatherings before people traveled home to nearly every state in the country.
The city of Sturgis is conducting mass testing for its roughly 7,000 residents. But health departments in at least six states are also trying to track outbreaks from the 10-day rally which ended on Aug. 16. Cell phone data has tracked rallygoers back to Arizona.