In many cases, the bacteria causes symptoms that feel like a prolonged “chest cold,” Dr. Singer said. These can include a dry cough, fever, headaches and fatigue. Children often develop head and ear aches, said Dr. Geoffrey Weinberg, a professor of pediatrics at the University of Rochester School of Medicine & Dentistry.

The persistent cough that has been nagging your child for weeks may be a type of "walking pneumonia." Here's what to know in California.