Jessica Turnbow was on mile 16 of her 19-mile training run for her first 26.2 at the Las Vegas Rock ’n’ Roll Marathon when a bee buzzed by her ear along the canal path in Chandler, Arizona. The canal paths were one of her favorite running routes, and she ran there often, even passing that spot just five minutes prior before she turned around to finish her run. The bee was persistent. Because of that distraction, and someone cutting grass nearby, she wasn’t able to see the swarm of bees around her. “Before I could even think, I had a...