“It springs up spontaneously, like little wildfires,” said Rob Crane, a medical doctor and president of Tobacco 21, a Dublin, Ohio-based advocacy group that supports raising the minimum age to 21. “These are folks who are your neighbors. When you approach city council members in a small town in California or Ohio or New Jersey, they listen.” In other public health news: made-to-order DNA, earwax, exercise, AIDS, and whooping cough.