Thanks, @David126. In case somebody is too lazy to open the link, I am pasting the text here, because it is a 'must read', in my opinion. I had a nurse respond to a post about this I made on Facebook about what has happened at her hospital; they have taken similar action. Her stories were nearly unbelievable, but true.
Text to article you linked here:
"Passengers who wish to take their support animal on board a Delta Air Lines plane will have to show proof of health and vaccinations 48 hours in advance, as well as other requirements, the airline said Friday.
Travelers with a psychiatric service or support animal will have to have a signed document "confirming that their animal can behave to prevent untrained, sometimes aggressive household pets from traveling without a kennel in the cabin," Delta said.
The new requirements start March 1.
Delta said animal "incidents" have increased 84 percent since 2016, including urination/defecation, biting and even a widely reported attack by a 70-pound dog."
Employees have reported barking, growling and biting from service and support animals, it said.
"Customers have attempted to fly with comfort turkeys, gliding possums known as sugar gliders, snakes, spiders and more," Delta said. "Ignoring the true intent of existing rules governing the transport of service and support animals can be a disservice to customers who have real and documented needs.""