Rabies vaccines are required by law, however if an animal has an autoimmune condition or severe allergic reaction to the rabies vaccine that would preclude a vaccine being administered then the tag for the county can still be purchased and a letter from the veterinarian can be submitted to the county indicating why the animal cannot be vaccinated. It is very rare to have this circumstance, however, and every animal's condition must be discussed with a valid Dr./patient relationship to determine what is best for the pet.
If there is a legitimate, medical reason for a rabies vaccine to be exempt, then a doctor is able to issue that but it requires an exam and discussion with the doctor. There are not many reasons why a pet would be medically exempt. Exemptions are not likely given for age or personal reasons.
Are you asking if you can get your pet worked on without it having rabies shots, or are you asking if you can decline it when they offer it?
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