The British concern about importation of rabies is long-standing, and represents at least one of the reasons a Channel Tunnel was not pursued to completion until relatively recently. (The "Chunnel" contains some design features to discourage particularly persistent animals from taking the trip on their own.) Some have described this concern as "paranoia", but I hesitate to do so, since the extremely stringent quarantine policy has kept Britain free of rabies for many decades.

At least the dog's owner is concerned about being able to say, for as long as possible, that "Frodo Lives". (If you don't understand this comment, it's impossible to explain. )