NEW YORK (CBS 2) — Pulmonary fibrosis is a disease that strikes otherwise healthy people and slowly makes them unable to breathe. It kills thousands every year, yet little is known about it, reports CBS 2’s Dr. Holly Phillips.

Bob O’Rourke is fighting for his life, and every breath is a breath to survive.

“When you get diagnosed with this, that’s a death sentence,” Bob O’Rourke said. “The breathing is your pain, and your pain is with you 24/7.”

O’Rourke has been diagnosed with idiopathic pulmonary fibrosis. It’s a disease that scars and deteriorates the lungs, ultimately robbing its victims of the ability to breathe, and it can strike without warning.

“I had a clean bill of health. I never had any medical problems,” O’Rourke said.

“They are often misdiagnosed as having walking pneumonia, COPD, asthma, or something else,” pulmonary specialist Dr. Joseph Lynch said.

O’Rourke was diagnosed four years ago, and he’s been living attached to an oxygen tank for the last three months.

“The lungs get very hard, and they don’t expand,” O’Rourke said. “It’s almost like somebody describing breathing through a straw.”

Pulmonary fibrosis has no known cause, and little is known about the disease except that it’s becoming more common. The illness kills 40,000 people every year – the same number as breast cancer – and there is no known cure.

O’Rourke’s CT scans show how quickly the disease is progressing.

“Right over here, you can see these areas where there are holes, and those holes are scar tissue,” Dr. Lynch said.

“The progression of the disease is frightening, because you don’t know when that’s going to take the nosedive,” O’Rourke said.

O’Rourke has been taking steroids to slow the disease, but the only way he can survive is with a lung transplant. He says what’s most important to him now is educating others.

“With all of my communications challenges, [my goal] is get the word out about this dreadful disease, that people need to know what it is,” O’Rourke said.

O’Rourke is hoping his fight can inspire others suffering with the illness.

Smoking and acid reflux can raise your risk of getting the illness, but most people who have pulmonary fibrosis did not have these risk factors.

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