During the 15-minute observation period after receiving his COVID-19 shot this March, Terry Harris pulled out his phone. There in the Vashon High School gymnasium, during a vaccination drive for St. Louis–area teachers, the executive director of student services at the suburban Rockwood school district in Missouri noticed an email addressed to himself and district superintendent Mark Miles. The subject line stood out: “Protect your people.”

A parent had forwarded screenshots from a Facebook group called Concerned Parents of the Rockwood School District. Commenters called Harris, who is Black, “the most racist guy towards white people you’ll ever meet” and said he “has to be the one that goes first.” Harris saw a photo had been posted of him and his daughter, and the worst panic attack of his life began. “I tried to get up, and I stumbled,” he says. Sitting in his St. Louis living room 2½ months later, wearing a T-shirt emblazoned with the word LOVE, Harris, 39, recalls being so shaken that a National Guardsman came over to offer him water.