Choosing a Vaccination Protocol for Your Dog

Originally published in TC Dog in 2005.

If you have a dog, you are likely aware of the current debate regarding which vaccines to use and how often they should be administered. So, what is the best vaccination protocol for dogs? The answer: it depends on the dog.

Vaccinations should be an individualized medical procedure rather than standardized based on species. Historically, every dog received the same vaccines, so an apartment-dwelling Maltese would get the same vaccines as a duck-hunting farm dog. Now, our goal is to vaccinate each individual animal no more frequently than necessary, and only against organisms to which they have a realistic risk of exposure and subsequent disease development.

The American Veterinary Medical Association (AVMA) and American Animal Hospital Association (AAHA) have published some guidelines to help establish a vaccination protocol for an individual dog. Vaccines are defined as "core" or "noncore." Core vaccines should be given to every dog. This is because either the organism is found everywhere, is highly contagious, causes severe illness or death, or represents a risk to human health. The core vaccines for dogs are rabies, canine distemper virus, canine parvovirus, and canine adenovirus-2.

Vaccines are considered noncore if the potential for exposure to the organism varies depending on geographic location or lifestyle and if the disease either resolves without treatment or responds readily to treatment. Noncore vaccines are recommended if an individual dog has a realistic risk of exposure to a particular organism. The noncore vaccines for dogs are canine parainfluenza virus, Leptospira spp., Bordatella bronchiseptica (kennel cough), Borrelia burgdorferi (Lyme disease), distemper-measles virus, canine coronavirus, and Giardia lamblia.

Using these guidelines, you and your veterinarian can determine which vaccines your dog should receive based on his or her risk of exposure and subsequent development of disease. Risk factors include age, lifestyle, exposure to other animals, present or future geographic location and current disease status. As an example, a dog's risk for Lyme disease depends on where he or she lives and travels. A Lyme vaccine may be recommended if a dog lives in, or regularly travels to, an area where Lyme disease is prevalent (endemic). In the seven-county Twin City metro area, Lyme is endemic in northern and eastern Anoka county, northern Ramsey county, and most of Washington county. So if a dog never leaves Hennepin county, a Lyme vaccine may not be recommended (but tick and flea preventative is a good idea).

Once the type of vaccines your dog should receive is established, the frequency of vaccination must be determined. There is no debate about frequency of rabies vaccination because this is established by government regulations. There is also no debate about frequency of vaccination of noncore vaccines, as these all have demonstrated duration of immunity indicating the need for yearly revaccination.

The controversy involves the frequency of administration in adult dogs of the "distemper combo" vaccine, which includes canine distemper virus, canine parvovirus, and canine adenovirus-2. The recommendation for annual revaccination is based on historic precedent rather than current scientific data. Data from challenge studies and the measurement of antibodies (serology) in dogs, indicate that immunity to these organisms may be sustained at least five to seven years.

Based on current scientific data, the AVMA and AAHA have published recommendations stating that core vaccines (with the exception of rabies) should be given every three years in adult dogs.

The measurement of a dog's antibody level for these organisms (antibody titer) has been suggested as a way to determine when a booster vaccination is necessary. However, significant variations exist among labs in testing procedures and interpretation of results, so the AVMA considers the measurement of antibody titers to be unreliable in assessing an individual animal's immunity.

It is important to remember that no vaccine is 100 percent effective or 100 percent safe. Like any medical procedure, vaccination has the potential to cause adverse effects. These effects vary from mild and self-limiting, to severe and life-threatening. The most common adverse effect is lethargy and a decreased appetite, sometimes accompanied by a mild fever, for a day or two after vaccination. Other, much less common effects include an allergic reaction (anaphylaxis), a benign swelling or mass at the site of vaccination, an infection or abscess where the vaccine was administered, the development or recurrence of immune-mediated disease, the development of mild symptoms of the disease for which the vaccine is against (residual virulence), and hair loss at the site of vaccination.

When vaccinating puppies, the core and noncore guidelines should be utilized. The currently recommended vaccination schedule for puppies with regard to frequency, and revaccination at 1 year of age, has not been questioned. Puppies generally receive their first vaccine between 6 and 8 weeks of age. This vaccine, which should include canine distemper virus, canine parvovirus, and canine adenovirus-2, is then boostered every three to four weeks until the puppy is at least 12 weeks old. The frequency of boostering in puppies is due to the presence of antibodies from the puppy's mother, called maternal antibody interference. Puppies have antibodies they receive from their mother which help them to fight infection after birth. If these antibodies are present when the puppy is vaccinated, they will process the vaccine, preventing the puppy's immune system from making his or her own antibodies. The maternal antibodies will gradually decrease in number as the puppy matures, reducing the puppy's immunity to disease. The goal of vaccinating puppies is to prevent a gap in immunity-while the number of antibodies from the puppy's mother gradually decreases, vaccines are given to allow the puppy's own immune system to come into contact with the vaccine, stimulating the production of the puppy's own antibodies. Vaccines are considered effective in puppies 12 weeks of age and older due to the reduction in maternal antibodies. This is the reason why puppies should be at least 12 weeks of age when they receive their rabies vaccine and the last distemper combo vaccine.

As we continue to gain more information about vaccines, you and your veterinarian can work together to customize a vaccination protocol that will be best for your dog.