According to my wife, the ER nurse:

"Shingles is contagious via air if in a large area (2 or more dermatomes) versus by touch if pustules are open and weeping but area is small. With her eye swollen shut, it's likely that 2 or more dermatomes were infected. That lady needed a MD note to fly. They probably could have done things more politely/privately but she shouldn't have been able to fly without clearance. Better they be cautious and piss someone off than endanger infants, immuno-compromised people or adults that have never had chicken pox. An adult that gets chicken pox likely gets admitted to ICU - way more dangerous than getting chicken pox as a child."