Dogs

How Does Vaccination Work

Vaccination helps prevent, not cure, disease. Vaccines contain disease-causing viruses or bacteria that have been chemically changed so they don't cause disease. When your dog is injected with a vaccine, the animal's immune system produces special substances called antibodies that work against the viruses or bacteria that cause the disease. Later, if your pet is exposed to that disease, these antibodies will help destroy those viruses or bacteria.
In many cases, vaccines against several diseases are combined, reducing the number of shots your pet must have. Despite progress to make vaccination as comfortable as possible, chemicals in some vaccines can occasionally sting when injected.
The protection provided by a vaccine gradually declines after a pet is vaccinated. That's why annual re-vaccination along with a health check-up is always recommended.

Why do Puppies Require a Number of Vaccinations?

A nursing puppy receives antibodies from its mother's milk (called maternal antibodies) that protect it from disease during the first month of its life. Unfortunately, these antibodies can also keep a vaccine from being effective.
These maternal antibodies gradually decrease during the first few months of the puppy's life. That's why puppies are given a series of vaccinations until they are 16 weeks of age or older. That way, if maternal antibodies interfere with early vaccinations, later doses will still stimulate the puppy to produce its own antibodies to the disease.

Which Vaccinations Are Required?

Your veterinarian will have a list of recommended vaccines, which may be changed to meet your pet's needs. Some factors the veterinarian will consider before beginning a vaccination program are:

	Age. Most vaccines have limited effectiveness until a puppy is weaned, because the maternal antibodies acquired through nursing may neutralize vaccine.
	Overall health. Poorly nourished or sick animals or those on some medications may not respond well to vaccination. That's why a physical exam is required.
	Need for diagnostic tests. An animal with parasites (like worms or fleas) or one infected with a disease may not respond to vaccination. Parasites weaken the nutritional and immunologic (immune system) health of the pet.
	Risk of exposure. Vaccination against some diseases may not be necessary if the risk of getting them is low.

A Word About General Health Care

Vaccines help protect your dog from infectious diseases, but other aspects of your pet's health are equally important, especially nutrition and parasite control.
Your veterinarian is your partner in ensuring the best preventive care for your canine companion and friend. See your veterinarian on a routine basis to keep your dog's vaccinations up to date, and follow his or her advice.
Your veterinarian can also keep you informed about new developments for providing a long, healthy life for your pet.

Some of the information on this page came from a Pfizer Inc. pamphlet