A veterinarian’s perspective on vaccinations for dogs and cats

The topic of vaccinations is hotly debated

There isn’t a hotter and more debated topic in small animal veterinary medicine than the topic of vaccinations. With different veterinarians and various political organizations in the field of veterinary medicine having different recommendations, including even many veterinary schools across the country, it can often be confusing for an animal guardian which vaccination(s) they should get for their dog or cat, as well as how frequently these vaccinations should be repeated. I’ll try and shed some light on this very confusing topic for the dog and cat owner.

As with my own approach to veterinary medicine, I personally believe that an individualized approach to this topic is needed for each pet. The risk of exposure to a particular infectious disease, as well as how severe the infection is (morbidity/mortality) , in terms of health risk to an animal are always the two most important factors I consider. In addition, I will also look at how long a vaccination has been on the market, and if it has been truly studied for safety long term, which in my opinion most vaccinations have not been adequately evaluated for long term safety, especially when repeated on a yearly or more frequent basis.

Most states do require dogs to be vaccinated for rabies by a licensed veterinarian, and many states also require cats to receive rabies  vaccinations. After the initial one year rabies vaccination (which I personally don’t recommend until the immune system is mature at 6 months of age) rabies vaccinations in most states are typically good for three years by law, after being boostered at one year of age. Studies are underway right now that will most likely demonstrate that immunity to rabies vaccination is good for at least 5 or 7 years; however, for now we must certainly follow the law with regard to this vaccination, given the public health  risk of rabies.

However, if an animal has a chronic medical or health condition that could be potentially exacerbated or worsened by a rabies vaccination, many states will allow a medical exemption by a licensed veterinarian in  that state  on an individual pet by pet basis. As for other vaccinations, in my opinion, many of them are given with too many viral/bacterial components in one injection, and many vets routinely give two or three combination vaccinations at one time. Especially in toy and smaller breeds, I have found this practice significantly increases the risk for not only short term acute vaccine reactions, but long term damage to the immune system as well, in addition to sometimes triggering chronic illness in sensitive pets. Vaccinations should definitely not be given at times of emotional, physical or hormonal stress, such as when a female animal is in heat, as well as around the time of a surgical procedure in my opinion.  And they certainly should not be given when an animal has any acute illness.

Over the past several decades the typical conventional standard of practice is to give puppies and kittens multiple viral vaccinations every few weeks starting as young as 3-4 weeks of age, up until 4-5 months old and then repeating that practice every year of the animal’s life. As Schultz and Phillips wrote many years ago in Kirk’s Current Veterinary Therapy XI edition (a text taught at many veterinary schools), yearly vaccination for core viral diseases is medically unnecessary, and is a practice that lacks “scientific validity.”  Immunity to most core viruses like parvo or distemper lasts for years to the life of the animal.  Although the first International Veterinary Vaccines and Diagnostics Conference held at the College of Veterinary Medicine in Wisconsin over 12 years ago (in 1997) concluded that the duration of immunity is likely more than 5 years for clinically important companion animal vaccines, many veterinarians still routinely over vaccinate both puppies/kittens and adult/senior dogs and cats.

Optional vaccinations like leptospirosis and Lyme vaccination in dogs, and Feline leukemia and FIV vaccination in cats are also not universally accepted as safe and/or efficacious by many. Evidence has emerged in recent years that over vaccination has been a major factor in the development of both the epidemic increases in autoimmune diseases, seizures, behavioral and hormonal disorders, and cancer seen in younger and younger pets. I have even read papers that document evidence citing genetic changes have occurred in pets at the level of their DNA because of the viral over vaccination process over so many generations of dogs and cats. With regard to flea and tick transmitted disease, certainly use of either conventional topical flea/tick medications, such as Frontline Plus, Advantage II, or more natural alternatives, offer better insurance against vector transmitted diseases than any vaccination in my opinion.

Regardless of what an animal guardian decides, this “veterinarian sensitive” topic should be discussed between client and veterinarian about what is best for their individual pet, and an animal guardian should certainly be supplied with as much accurate and unbiased information on this issue as possible, in order to make as well informed a decision on which vaccinations their pets truly need. The product Vetri-DMG liquid is often quite helpful at time of vaccination and in the subsequent 10-14 days post vaccination to not only improve immunologic response to a vaccination, but to help modulate the immune system response so that the likelihood of vaccination reactions is decreased.

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  1. I have a 13yr old mixed breed dog and when I took her to the vet last year for her shots he said she wouldn’t need them anymore after that coz they’re really not nessesary in dogs over 13. How can that be with parvo still out there and rabies, and distemper? Is this a rule or can I still get her shots in February, she turned 14 in October.

  2. Hi Claudia, I don’t know if anyone ever got back to you, but I would treat first check her records from that visit to the vet in 2008? See which ones of the “known-to-change-quickly” viruses/diseases like parvo, distemper, etc.,
    Do your research. A short time on Dr. Dym’s Blog archives can tell you alot. For example, smaller breeds like yorkies, is not necessary and possible dangerous to give rabies vaccination anything less than 3yrs apart. I would read a recent blog that discusses specifically parvo virus. If it were me, I would never stop giving my dog his heartworm medicine becuase someone told me he’s too old and you’re hurting his liver. (Someone did tell me that..then I realized I was nuts to listen to that).
    Get the absolute necessary ones -Make a new list based on the vet record from the year prior. See what the expiration dates of what shots she had and do some research on this site..

  3. Dr. Michael Dym, VMD veterinarianJune 19, 2010 at 9:34 pm

    HI Maria: Thanks for your kind comments, as well as wonderful advice to Claudia. As someone who has a big interest in the overvaccination issue of dogs, and is well read on the topic, I can tell you and Claudia that from conversations with veterinary experts such as prestigious immunologist Ron Schultz, PHd from Wisconsin vet school and Jean Dodds, DVM, that if dogs are vaccinated for parvo or distemper over 16 to 18 weeks of age that immunity lasts MANY years if not the life of the animal. If needed vaccination titers can be measured to document immunity. Increasing evidence is suggesting that overvaccinating dogs, especially with polyvalent multiple viruses all at the same time can overwhelm the immune system and can be risk factors and/or causative agents of not just acute reactions, but chronic disease in our pets. With the new research being done on rabies immunity http://www.rabieschallengefund.org, hopefully research will soon be published documenting very long term immunity to rabies as well as likely 5-10 years at least, so that hopefully we can get the laws changed. However for now, unless an animal has a preexisting chronic medical condition, we must follow the law with every 3 year rabies vaccination in most states. Medical exemptions though can sometimes be written in various states if a pet has a chronic health condition that could potentially be made worse by vaccination.

  4. Thank you, Dr. Dym. I value and would never challenge your professional, medical opinion. I hope Claudia has done the right thing by her dog.
    I love that this blog is available to us pet ownersto relay their situations and seek advice. You really are a great assest to all of us. I value the information I’ve obtained from reading your blogs. I hope you continue; and know how appreciated and valuable your service is to the online community.
    In staying with this topic, remembering the 4hours in the waiting room at the vet the day they had a ‘more important emergency’, I specifically recall exactly the sad result of most likely polyvalent multiple vaccines-
    A yorkshire terrier was in for “routine vaccinationS”. I know, because I was speaking to the dogs ‘mom’ while she calmly waited for this “routine” visit to be over and for them to bring her li’l doggie out. She went to check out, her yorkie by her side. Before she finished checking out, the dog urinated several times, started having trouble breathing.Within 30 seconds, the dog was in the back with every nurse, vet tech and the only 1 Dr on staff trying to save it’s life as the owner is now in hysterics.The Dr. comes out to tell the owner the dog is in anaphylactic shock from the vaccines but they don’t know which one. This poor dog couldn’t have been more than 7 or 8 pounds. I never found out what happened but I never went back there. The dog was given MULTIPLE vaccines and they didn’t know WHICH one was causing it. My uneducated guess being a former biology major and coming from a family of anesthesiologists was …….all of them!!!

    I’m glad that you brought this awareness to the public; not only in this blog but in another blog specifically about small dogs or yorkies. Thanks again for your information.~Maria.

  5. Dr. Michael Dym, VMD veterinarianJune 30, 2010 at 12:44 am

    You are very welcome Maria. This information MUST be spread to your friends, family and hopefully ultimately the media. What is going on with this overvaccination craze of our pets across the country is in my opinion genocide and unproven in safety long term. Most of the core viral vaccinations have life time immunity and should not be given at time of surgical stresses or illness and/or in combination with other vaccinations. The data is all there and yet many vets continue to ignorantly practice polyvalent shot jockey vaccination medicine. This information must somehow also get out to the public through some sort of additional forum in the media, as well as continued on the 1800petmeds website. Thanks for your comments and definitely spread the word. Animals are being damaged and maimed every day across this country and the reporting system of reactions is pathetic, as most vets dont even know what a vaccination reaction is. There is ALOT more than just an acute anaphalactic reaction to vaccinations that can occur days, weeks or even months later when overused in our dogs and cats.

  6. Dr. Michael Dym, VMD veterinarianOctober 25, 2010 at 8:27 am

    I usually give two parvo/distemper vaccinations at age 12 and 16 weeks of age. Then a rabies one month after final distemper shot should give long term immunity.

  7. Dr. Michael Dym, VMD veterinarianJanuary 26, 2011 at 12:33 pm

    Most important aspect of any good health is a natural and minimally processed diet. 1800petmeds now has a big variety of natural foods available including ones like Halo and natures variety. As for vaccinations, I am a minimalist when it comes to vaccinations. In my practice I only recommend vaccinating for parvo/distemper and not all of the other polyvalent vaccinations, except for rabies as required by law. Usually two vaccinations at age 10 and 14 to 16 weeks of age is enough to give long term protection and immunity that lasts years. Rabies should be given at age 4-6 months separate from other shots. Worming is usually done at age 3-6 weeks of age. Puppies can then be started on monthly heartworm prevention which helps control and prevent intestinal worms, in addition to heartworms. Flea and tick control I usually wait until they are over 3 months of age. Frontline and advantage are useful products, and there are other natural alternatives as well, for those clients who prefer less pesticides, however these other methods sometimes dont work as well and do require more persistance than the monthly drops.

  8. hi i have a soon to be 6yr old male pit bull and i was wondering how often i need to have him get the parvo shot?? when he was a puppy the man i bought him from got all of his shots including the parvo shot..please let me know bc i want to know and keep him up to date..bc while i was gone my friend took care of him and he got attacked and i dont know all of the shots he was given..thank you so much for your time..

  9. i have a soon to be 6yr old male pit bull and i was wondering how often im suspose to get the parvo shot done.when i bought the dog the man had already gotten all of his puppy shots including the parvo shot..my friend had to take care of my dog while i was gone out of town and my dog had gotten attacked and i dont know of all the shots he was given and i just want to know how often my dog needs the parvo shot…please let me know and thank you so much for your time..

  10. Dr. Michael Dym, VMD veterinarianMay 14, 2011 at 12:01 am

    Parvo vaccination immunity typically lasts for years to life of pet. AT least 5 years immunity.

  11. Dr. Michael Dym, VMD veterinarianMay 14, 2011 at 12:01 am

    See response below

  12. I have a concern for my dog Lassie. He is a rough collie and up until about 3 years ago always had each shot our vet recommended. Due to money being tighter he has only gotten like the rabies vac. for the past 3 years. He had a parvo shot about 5 years ago. How often is this shot needed? Is he still protected against this disease? Should I be concerned that he is in need of another one? If you have any advice in my situation please reply. Thank you so much.

  13. Dr. Michael Dym, VMD veterinarianJuly 5, 2011 at 5:14 pm

    Immunity to parvo virus often lasts for years to the life of the pet. You can ask your veterinarian to measure a parvo vaccination titer, which is a blood test that can document likely protective immunity. Parvo is mostly seen in unvaccinated puppies under one year of age. Rabies vaccination should be given only every 3 years in most states as well.

  14. Can you purchase the rabie vaccine to give to your dog.

  15. Dr. Michael Dym, VMD veterinarianMay 11, 2014 at 9:17 pm

    Most cases rabies vaccination can only be purchased by licensed veterinarians.

  16. I adopted a Eng Bull Terrier of 5 years about 4 mo ago.
    His rabbies is up to date but what other vaccination should/can I use to protect him? I live in Northern AZ, my dog goes inside and out. Sociallizes with neighbors dogs and sometimes ones at the park. I want to set him up to stay happy and healthy.

    Thanks… S. Day

  17. Dr. Michael Dym, VMD veterinarianJune 13, 2014 at 6:37 pm

    If her were my dog, given the immune sensitivity of this breed, I would ask your local vet to measure vaccination antibody titers against parvo/distemper. If these are adequate, then no further vaccination is necessary or needed. Those are the only other main diseases I look at, as I try not to over vaccinate our animals.

  18. Pingback: The Dangers of Vaccinations: Be an Informed and Proactive Guardian for Your Beloved Animals - Love Healing and Miracles

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