How often should your dog be vaccinated?

To vaccinate or not vaccinate your dog--that is the question.

I have always believed that vaccinating my dogs against distemper, parvovirus, hepatitis, leptospirosis, and parainfluenza was important and necessary to protect their good health. However, recently I've begun to question whether or not it is right for my dogs.

Many veterinarians are divided into two groups on this subject. Some still believe dogs should be vaccinated every year for all infectious diseases, whether or not the dog still has immunity and if they have exposure to them. Others believe in a more natural approach, and that vaccinations are actually poisoning the dog and are causing more diseases than they prevent. Most already agree that cats should now only be vaccinated every three years for distemper, and if they have no exposure to feline leukemia, that they not be vaccinated against it because of the number of cats that developed sarcoma (cancerous tumors) at the vaccination site. No such decision has been reached about dogs at this point, although many dogs have developed tumors as well at the vaccination site, and are also showing anaphylaxic reactions to the vaccines. Some have reported dogs becoming aggressive after repeated vaccinations. It's believed that the immune system becomes compromised from exposure to too many viruses and causes an allergic reaction.

One suggestion I've seen is to talk to your veterinarian about running an annual blood test which shows how much immunity your dog still has to these diseases, and therefore helps determine if a booster is needed or not.

I've been on the fence on this issue ever since I heard about the controversy, as I don't want to needlessly expose my dogs to problems from the vaccines, but I want to be sure they're protected. How do you feel about it; have you made any decision as to whether to allow vaccination every year or not?