About 450 children have been treated at Children's Mercy Hospital in Kansas City
Virus comes on as a cold before developing into respiratory distress
Centers for Disease Control and Prevention testing whether it is an Enterovirus D68 or EV-D68, a respiratory infection with varying symptons and levels of intensity
There is no proper treatment or vaccine for EV-D68
Doctors have been treating severe cases with ventilation
Outbreaks also reported in Colorado, Illinois and Ohio