CHICAGO (CBS) -- It's called Myalgic Encephalomyelitis or Chronic Fatigue Syndrome and it affects 17 million people worldwide.
"This particular illness is more functionally debilitating than chronic congestive heart disease and cancer. The quality of life is significantly less. There's over a million people in this country with this illness, 25% are homebound or bedbound," said Leonard Jason, DePaul University, who's been studying the disease for 25 years.
"We are currently studying it to see where it develops. We are watching several thousand undergraduates who might develop mono and we're following them over time. A lot of people indicate the virus that causes Mono triggers this."
Jason says most people don't even know they have it.
"Ninety percent of people have it non diagnosed. There are a lot of people that are sick, don't know why they are sick and that's what they have."
Amy Moony's 11 year old daughter was diagnosed two years ago.
"She got a random bug when she was 9 years old and it never went away. We never knew what it was. It was something that changed her systems and triggered her autoimmune and caused a spiralling condition."
Moony says they've had to change their life because of it.
"We have to be quiet around the house all the time. We can't go biking as a family, we can't go to the movies anymore. Our lives revolve around my daughter's disease."
That's why she says she's leading Chicago's day of action, where in front of the Thompson Center, dozens of pairs of shoes line the pavement.
"The shoes represent people who suffer from ME and are home-bound and couldn't come to the protest," said Moony.
She says ME is one of the least funded diseases so more needs to be done to help people like her daughter.
"She lives it every moment of the day. She has constant pain. She can only go to school for an hour before her head and body rejects. That's her day, then she goes back into bed until evening.
Jason says increased funding is needed for research, clinical trials and medical education into the disease.
"We want basic research so we can help people with treatment and eventually cure this illness but it's a long process that's going to need money to make it happen," he said.
"We are hoping that people become aware of the name and that when somebody walks into their doctor's office they aren't told they just need to rest because rest will not fix the problem. It's something we need more medical personnel to research and acknowledge and verify that this isn't a person's psychological condition. We need our government to put money behind this disease."
Symptoms of ME include headaches, muscle/joint pain, unrefreshing sleep, sensitivity to light, cognitive impairment and constant fatigue, where normal tasks are exhausting to near impossible.
The Chicago rally was part of an global day of action to bring attention to ME and the people who suffer every day.
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