Respiratory Syncytial Virus is a respiratory illness that can be deadly.

“This virus attaches itself to lung tissue that burrows in and hangs on and then spread itself over the cells,” Dr. Florence Nolan, pediatric cardiologist, said. “The cells ultimately cause inflammation and cell destruction, it's a nasty virus."

RSV in older kids or adults is much like the common cold, but spells trouble for premature babies.

"As a child if you have underlying lung disease, lung disease like prematurity, you are going to be very sick and potentially die with RSV," Dr. Nolan said. "Sometimes the presenting symptom in a baby is stopping breathing. They will have retraction—it's when the skin on the ribs gets sucked in when they breathe. They have a very commanding cough and working very hard to breathe."

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