Conversation reported and produced by Andrea Dukakis.

It’s a frightening sound for a parent - a child with whooping cough, or Pertussis. This year is proving to be a bad one for the illness in Colorado. Cases are higher than they’ve been in recent years and are spread across more counties than in the past.
Jeff Dimond is a spokesman with  the Centers for Disease Control and Prevention in Atlanta. He specializes in immunizations and respiratory diseases.