A genetic disease that is passed down to an offspring inherits two copies of a defective gene. Some symptoms include production of thick mucus brought on by chronic coughing, and repeated bouts of pneumonia.
In a similar way that a wheelchair would be used for COPD, Cystic Fibrosis victims may at some point, require a wheelchair to get around. Some cases of this disease would still allow the user to propel them; they can get a manual big-wheeled wheelchair that would allow them to maneuver on their own.
With more severe cases of Cystic Fibrosis, the person may need a transport or companion wheelchair to allow someone other than himself or herself to push them. This disease is incurable, which means that at some point the person may require a more advanced type of wheelchair, such as a standing wheelchair or a tilting wheelchair.