Will Falconer, DVM Moderator
Hey Lorraine,
International travel: all bets are off. You are controlled by forces greater than I can help you with.
At your vet? A whole different story, but you have to be smarter than the vets on duration of immunity (search that phrase on this site and you'll get right up to speed). And then, speak confidently that more vaccines are not something you will be giving your already-vacc'd pup. No fine, no forcing (though they may try).
There's absolutely no basis in immunology for annual rabies vaccination. None. Will they try to arrest you for being wise about this? Not if you present it from a confident position and politely decline future shots. (And really, nowhere in my knowledge does a vet have any kind of law enforcement capacity, and I doubt if Spain is any different in that regard.)