There are several opinions about vaccinating dogs. It is our job as veterinarians to inform and educate you--our client--so you know which vaccines are necessary for your pet. Not all dogs share the same "level" of exposure and some vaccines are "protective" for longer periods of time than other vaccines.
Unfortunately there are many ways for your pet to be exposed to disease-causing organisms. Healthy-appearing animals can spread viruses and bacteria and you may unknowingly carry disease-carrying organisms on your hands, clothes, or shoes. Vaccination is the best way to prepare your dog's immune system to prevent disease when they are exposed. Additionally, using proper hygiene is also important.
There are "core" vaccines and "optional" vaccines.
The "core" vaccines are:
"Distemper/Parvo" (or"5 in 1") and Rabies. After their first adult booster (at 1+ year old), these vaccinations will be protective for 3 years, if your veterinarian has the appropriate vaccination. It is better to vaccinate less often for these diseases, as over-vaccination may actually cause autoimmune disorders and cancer.
You can also discuss with your veterinarian doing a vaccination titer. This is a blood test that will determine if your pet has enough immunity to these diseases, which may allow for a longer period of time between vaccinations.
The "optional" vaccines are:
Lyme, Leptospirosis, Bordatella (kennel cough), Canine Influenz, Coronavirus, Porphymonas, and Giardia. There is a lot of literature online about these diseases.
Be sure you discuss disease exposure with your veterinarian to decide which vaccines are necessary for your pet. This will lessen the likelihood of over-vaccinating your pet.