(NEW YORK TIMES) — Before the media vans took over Main Street, before the environmental testers came to dig at the soil, before the doctor came to take blood, before strangers started knocking on doors and asking question after question, Katie Krautwurst, a high-school cheerleader from Le Roy, N.Y., woke up from a nap. Instantly, she knew something was wrong. Her chin was jutting forward uncontrollably and her face was contracting into spasms. She was still twitching a few weeks later when her best friend, Thera Sanchez, captain of one of the school’s cheerleading squads, awoke from a nap stuttering and then later started twitching, her arms flailing and head jerking. Two weeks after that, Lydia Parker, also a senior, erupted in tics and arm swings and hums. Then word got around that Chelsey Dumars, another cheerleader, who recently moved to town, was making the same strange noises, the same strange movements, leaving school early on the days she could make it to class at all.