Donovan Yoo is a beautiful and energetic baby boy with big brown eyes and a flirty smile. He has strong, pudgy arms and chunky, little baby feet. He is 19 months old, so understandably he wants to explore his world. He crawls very carefully on the hardwood floors of his family’s three-bedroom house in Walnut, Calif.

A light beige ventilator pumps air rhythmically in the center of the room. Donovan feels that familiar tug at his throat. He knows that the tracheotomy tube that connects him to his ventilator is about to pop off. Once he feels it disconnect, he giggles and makes a run for it — crawling twice as fast as normal. But within one minute, the toddler gasps. He has run out of breath.

His father, Richard Yoo, 30, calmly reattaches it, and Donovan takes another breath.

Donovan has Congenital Central Hypoventilation Syndrome (CCHS). CCHS is a very rare and serious nervous system disorder in which the automatic control of breathing is impaired or absent. There are an estimated 500 reported cases in the U.S. of the condition, which is caused by a genetic mutation. There is a 50 percent chance that one of Donovan’s parents carries this gene, but it’s also possible neither does.

The disease has been referred to as “Ondine’s curse,” based on the mythical story of Ondine, a water nymph who discovers that her mortal lover is unfaithful. The king of the nymphs puts a curse on the man that causes him to forget to perform all bodily functions, including breathing. So when the mortal falls asleep, he “forgets” to breathe and dies. The medical community today generally tries to avoid the term “Ondine’s Curse” because children with it don’t “forget” to breathe.

CCHS is a severe form of sleep apnea. Anytime while asleep, a CCHS infant may stop breathing and possibly die. Some scientists believe that there may be a connection between CCHS and Sudden Infant Death Syndrome.

Dr. Anchalee Yuengsrigul, a pediatric pulmonologist at Children’s Hospital of Orange County, says healthy people have a breathing control center that regulates the body’s response to carbon dioxide levels in the body. With CCHS patients, the breathing control center fails to work properly, meaning they are at risk of having toxic levels of carbon dioxide in their body without a ventilator.

Typically, a CCHS child only needs a ventilator at night or occasionally throughout the day, but because Donovan’s condition is severe, he requires 24-hour ventilation. Three hoses go into a band around his neck. His 27-year-old mother, Caroline, keeps a soft blue receiving blanket over his throat — a gentle touch for a little boy who has endured some not so gentle procedures in his less than two years of life. 

Because CCHS is often associated with other diseases, Donovan has already had several surgeries and other medical procedures. Doctors removed part of his colon when he was less than a month old to treat a bowel disorder called Hirschprung’s Disease. Donovan has also had a tracheotomy surgery, an ear-tube procedure and a feeding tube procedure. He has had a tumor in his arm, also related to his CCHS, removed.