DENVER (CBS4) – A Denver hospital is packed with children suffering from a respiratory virus called RSV, and doctors want to get the word out that the disease is spreading and could be dangerous, even deadly, for some infants.

Parents have been dealing with the enterovirus, then the flu, and now RSV. Rocky Mountain Hospital for Children has been slammed with infants struggling with the respiratory illness. Some are so sick they need help breathing.

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Calvin Height (credit: CBS)

Calvin Height (credit: CBS)

Six-week-old Calvin has spent the last 11 days in intensive care with his worried parents at his crib side.

“There were some scary moments,” Calvin’s mother Amanda Height said. “It was very frightening; it was one of the worst things you can even imagine as a parent.”

It started Monday, Feb. 9 with a cough. Height’s pediatrician told her to keep an eye on the baby. On Thursday Calvin was vomiting, so they took him to an emergency room.

“He seemed fine. Just was a virus, they said,” Height said.

Within 24 hours Calvin was rushed to the hospital.

“Basically he couldn’t breathe.”

The baby was quickly put on a ventilator.

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“I immediately broke down,” Calvin’s father said. “The nurses asked me if I needed anything, and I told them I needed to know he was going to be okay.”

Calvin Height's parents talk with CBS4's Kathy Walsh (credit: CBS)

Calvin Height’s parents talk with CBS4’s Kathy Walsh (credit: CBS)

Calvin was diagnosed with RSV, a common respiratory virus that Dr. Matt Gollub says usually causes a bad cold. It hit Calvin hard.

“When he got here he needed a lot of help,” Gollub said.

Currently at the Rocky Mountain Hospital for Children nearly half of the rooms in intensive care have babies fighting RSV. Last year through February the hospital had 82 cases. This year as of Feb. 18 there have already been 136.

There is no cure for RSV.

“Just like the cold it’s up to the body to fight it off,” Gollub said.

The Heights want other parents to know it strikes fast.

“Monday I was at the zoo with him, and Friday he was in the ICU,” Height said.

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RSV can spread easily with coughing and sneezing. Doctors say to wash hands, keep babies away from sick people, other young children and crowds. They also say to be proactive and get a sick infant to the doctor.