WASHINGTON -- New York lawyer Adrianne Ryan said her toughest fight wasn't swaying a jury. It was persuading people that her chronic fatigue wasn't all in her mind.

The Centers for Disease Control and Prevention unveiled an awareness campaign to highlight Chronic Fatigue Syndrome.

Chronic fatigue has been a mystery to doctors, from how it develops to methods of treatment, CDC Director Julie Gerberding said.

Ryan was an athlete and was accustomed to pushing through pain. But her chronic fatigue would get better, and suddenly return. She withdrew from her friends and family. She was unable to get precise medical help. And she had to fend off well-meaning people who told her that her illness was all in her mind, and that she could be cured by positive thinking.

Several years after contracting the disease, her health has finally returned, Ryan said.

The illness affects at least one million Americans, the CDC said. Women are four times as likely to be affected as men, and minority women are affected at a rate greater than white women.