Vaccine Side Effects in Dogs and Cats

Vaccinations for dogs and cats

Increasing numbers of vaccinations for dogs and cats have become available over the past few decades. While vaccination for certain core viruses is certainly important, too many vaccinations given too frequently may lead to the development of chronic disease and even cancer in some sensitive pets.

Many veterinarians vaccinate puppies and kittens every 1-2 weeks at a time when their developing immune systems cannot handle the onslaught of too many viral components. Although young puppies and kittens exposed this frequently to vaccine antigens may not demonstrate overt adverse effects, their relatively immature immune systems may be temporarily or more permanently harmed. A "less is more" individualized approach for each pet is preferred when developing vaccination programs for dogs and cats.

Key facts about vaccine side effects in pets
  • Vaccination for certain core infectious diseases is important, but too many vaccinations given too frequently may lead to the development of cancer or other chronic diseases.
  • After vaccinating puppies and kittens at 16 weeks old, immunity to core viruses parvo and distemper may last for several years to the lifetime of your pet.
  • In adult and senior pets, it may be better to measure vaccination antibody titers as a more healthy option instead of vaccinating needlessly.
  • If your pet is suffering from acute or chronic illness after vaccination, it is best to consult with a veterinarian skilled in recognizing and treating these diseases.
Recommended medications for treating vaccine side effects in pets
Which caccinations do dogs and cats need?

Distemper and parvo virus are the two chief core viruses most dogs need a vaccination for. The two-in-one parvo/distemper vaccination given at eight, 12, and at 16 weeks of age should offer long-term protective immunity for most puppies. Other vaccines, such as vaccines for adenovirus, coronavirus, Bordatella, influenza, giardia, and leptospirosis are usually not needed in most cases.

For cats, the feline panleukopenia virus is the main vaccination that is needed. Injectable feline rhinotracheitis and feline calici virus are not nearly as effective as the feline panleukopenia vaccination. The three-in-one vaccaintion for panleukopenia/rhinotracheitis/calici virus given at eight, 12, and 16 weeks should offer long-term protective immunity for most kittens.

Due to the human health risk and legal requirements, all pets must be vaccinated for rabies after four months of age. Rabies boosters are given again when your pet is one years old, and then again every three years as required by law in most states. Pets with chronic diseases and cancer may sometimes be eligible for medical exemptions from rabies vaccination, because in those cases the risk of vaccination may outweigh the benefits.

Vaccination titers (blood tests) as an alternative to vaccines

Vaccination antibody titers are blood tests that may be performed by veterinarians instead of routinely vaccinating pets. Vaccination titers measure blood antibody levels and can document whether further vaccinations are needed for core viruses. In most cases, pets vaccinated adequately as puppies or kittens typically have high antibody level protection against core viruses, and no further vaccinations are needed. If vaccination titers are low, then booster vaccinations may be considered, depending on the lifestyle, health, and age of your pet. Another option for pet owners includes the use of homeopathic remedies known as nosodes, which are made from dilute extracts derived from pets that have an infectious disease. Administering homeopathic nosodes to pets at or just prior to potential disease exposure may provide future protection against live viruses. Nosodes are available for canine distemper, parvovirus, and bordatella, as well as feline panleukopenia and feline leukemia virus.

Although many holistic veterinarians have used these nosodes successfully in practice, there has been no convincing evidence that nosodes prevent disease. The results of one controlled clinical study suggest that parvo nosodes are completely ineffective in preventing parvoviral disease under experimental challenge conditions.

Non-core viral vaccinations and leptospirosis or Lyme disease

Although vaccinations are available for canine diseases such as leptospirosis, Lyme Disease, Bordatella, and influenza, the long-term safety and efficacy of these vaccinations is questionable, so their use in clinical practice is not routinely recommended. In fact, many holistic veterinarians have reported chronic joint, liver, or kidney problems in dogs vaccinated for Lyme Disease and leptospirosis. Behavioral issues, skin problems, and thyroid disorders have also been seen in dogs vaccinated repetitively with core and non-core vaccines.

Examples of feline non-core viruses and bacteria include feline leukemia virus, feline immunodeficiency virus, feline infectious peritonitis virus, and chlamydia . In most cases, use of these additional vaccinations is not necessary or recommended. For outdoor cats, vaccinating only kittens under one year of age for feline leukemia is recommended, since kittens of this age may be susceptible to the virus. Most healthy adult cats will develop their own innate immunity on exposure to feline leukemia virus; therefore vaccination is not usually needed.

Max's Tip

Consider vaccination antibody titers for adult and senior dogs and cats, and for sensitive pets that have previously had a reaction such as fever or swelling after receiving a vaccine.