Don’t Vaccinate Your Adult Cat for Distemper! by Jean Hofve, DVM

May 25, 2012
By Jean Hofve, DVM

Seriously? Yes! Evidence is mounting that the common FVRCP (feline viral rhinotracheitis, calicivirus and paneleukopenia) vaccine may cause long-term damage to cats’ kidneys that increases with every booster. Here’s the report from Colorado State University:

The Center for Companion Animal Studies at Colorado State University has shown that cats vaccinated with FVRCP vaccines grown on Crandell-Rees Feline Kidney (CRFK) cell lines can develop antibodies to renal proteins, and that cats hypersensitized to CRFK cell lysates can develop interstitial nephritis…Cats administered FVRCP vaccines parenterally (by injection) have higher levels of circulating antibodies to these antigens than do cats who were administered a FVRCP vaccine for intranasal administration.

Similar antibodies have been implicated in the development of renal disease in humans, and there is every reason to suspect that they do the same in cats. Chronic renal failure (CRF), also called chronic kidney disease (CKD) in cats is known to be caused by chronic interstitial nephritis, or inflammation of kidney tissue–the very thing that these vaccines cause.

Fortunately, the distemper vaccine is extremely effective and long-lasting. A kitten that receives its initial vaccine series, or any kitten or cat vaccinated just once after 16 weeks of age, is protected for life. There is no benefit, and substantial risk, to repeated distemper vaccines in adult cats.


Note: two questions were asked by a reader. Please see Dr. Hofve’s response below:

How do you know that one injection won’t cause lifelong increased antibodies to renal proteins? That would be my assumption. If one shot can immunize for life, couldn’t one shot cause CRF over time? Are any distemper vaccines grown on cells that are not cat cells or similiar?

Holistic veterinarian and author Dr. Jean has 18 years’ experience in conventional and alternative veterinary medicine. She has a passion for feline health and nutrition is the former Editor-in-Chief of The American Holistic Veterinary Medical Association Journal. For more information, please visit the library at Dr. Jean’s website,

  • Tweet

Tags: , , , ,

27 Responses to Don’t Vaccinate Your Adult Cat for Distemper! by Jean Hofve, DVM

  1. Erin on July 1, 2018 at 4:15 pm

    Not buying this completely. I have two adult indoor cats who have only been vaccinated every five years. I lost an adult cat to distemper once. Maybe had I taken her to the right vet it would have been ok, but she had her vaccinations as a kitten. I cannot in good conscience not protect my cats from a disease that could be brought inside on my shoes or clothing as unlikely as that may be. I absolutely don’t think they need a shot ever year.

  2. Cheryl on June 24, 2018 at 12:05 am

    G,day, I recently since April have had 5 lil kittens get feline parvovirus,2 have passed away before the vets knew what was wrong, the other 3 spent time on iv drips. They have pulled thru but my house is also home to quite a few young and older cats, all had been vaccinated from the time they arrived. My problem is that now I have had 6 others come down with the virus after been told that they couldn’t get the virus once fully vaccinated. Ha, that was totally wrong. On top of that I have also had lost a lot over the years with Renal failure and cancer. I honesty have no faith in any vaccine for either my dogs or cats. I live in Australia by the way.

  3. Kitty on May 4, 2018 at 7:18 am

    Recently I trapped an adult feral cat and when I took him in to be neutered I was told that there was no point to giving him a FVRCP vaccine if it wouldn’t be boostered in 3 weeks. They said that without the booster there would be no benefit.
    They did say they use a MLV vaccine.
    I thought an adult would receive protection from a single MLV vaccine?

  4. Lola on March 20, 2018 at 9:36 pm

    So is it safe for Adult cats not have the F3 vaccince (assuming they’ve had all their kitten vaccinations) I will be adopting a pair of 2 and 1 year old cats and after having my previous cat have to be PTS at age 18 due to renal failure i really want to do all i can to prevent renal failure in my new adoptees. I guess what my question is since the F3 vaccine vaccinates against all 3 viruses, how do I vaccinate against the other 2 viruses and just eliminate parvo vaccine? Or is what you are saying is dont do the F3 vaccine as a whole?

    • Lola on March 20, 2018 at 9:47 pm

      “Fortunately, the distemper vaccine is extremely effective and long-lasting. There is no benefit, and substantial risk, to repeated distemper vaccines in adult cats.” but what about the vaccine for the other 2 viruses?

    • adminjr on March 21, 2018 at 11:22 am

      Lola, I asked Dr. Hofve your question. She responded: There are many different distemper (panleukopenia) vaccines with up to four components, including panleukopenia, calicivirus, rhinotracheitis, and chlamydia. The other three components do not provide immunity, but may help minimize symptoms when the cat gets the disease.

      However, if they have had their kitten vaccines, no further vaccines are necessary (except rabies as required by law). See:

      • Lola on March 21, 2018 at 9:17 pm

        Thankyou so much for your quick response :)! I thought maybe i wouldn’t get a reply. I’m here in Australia and doing extensive research before I adopt these cats. I want to make sure i know as much as i can this time round. We dont have rabies in Australia fortunately so no vaccine required for that yay!

    • Noofies on April 9, 2018 at 2:28 pm

      Lola, you’ll also want to feed a feline-appropriate diet. No dry food, period. Canned food only or, if you’re feeling brave enough, raw food.

      • adminjr on May 4, 2018 at 1:02 pm

        Noofies and Lola — I absolutely agree!

        Dr. Jean Hofve says: They have it exactly backwards. Killed vaccines, like rabies, require a booster to produce full immunity. You are correct that just one MLV vaccine provides full protection for an adult cat.

        Check out her terrific articles on

  5. Carol Morris on December 13, 2016 at 10:31 pm

    I am sure some DVM’s are aware of this. And dangers of re-vaccinations. Even holding shot clinics. Uninformed go to these clinics thinking they are protecting their beloved pets. Even some DVM’s push giving 5 to 6 injections!!. I witnessed this with my new Siberian kitten. And said, “no more vaccinations” for him. I feel this is wrong. It pads their wallets a bit. But most of all goes against their medical creed of “first do no harm”. When will the truth come out? It’s not in the best interests of the animal. I am aware this group of medical professionals is not regulated but they sure as heck should be!

    • adminjr on December 14, 2016 at 9:47 am

      Carol, your sentiments are mine. Cats, dogs, babies and adults have suffered from the profit-taking of over-vaccination. Drug makers will surely continue to do harm as long as it is profitable to do so.

    • Nadia Repich on May 15, 2017 at 3:56 am

      Vets are not bound by the medical creed to do no harm. Pets are property as all animals are. Please read the article Veterinarian Heal Thy Profession by Joel Marks philosopher.

      & you can visit me on FB to get the entire picture.

    • sam on October 4, 2017 at 10:10 am

      PLEASE PLEASE be careful when vaccinating with FVRCP. Our 6 yr old cat died within a week of getting the FVRCP vaccine with clear signs of kidney failure.

  6. Catherine on September 19, 2016 at 9:01 am

    Hello. I came across your site after doing some research on vaccines for my new kitten. I read on another site called that it’s dangerous to vaccinate the recommended 5 times for kittens for distemper and that if you start wth the first shot at 9 weeks of age and a 2nd shot at 16 weeks that’s enough for their lifetime. Do you agree with that or just the one at 16 weeks is sufficient? I already gave my Oliver one distemper at 9 weeks and his 16 week appointment is coming up in the next week so I hope to have a recommendation from you before then.

    • adminjr on September 19, 2016 at 9:55 am

      A reply from Dr. Jean Hofve: Hi Catherine,

      For a kitten with a known history, as is your case, the 9-wk and 16-wk vaccine schedule are fine. The 9-week vaccine covers the period (which varies) when the immunity received from the mother may no longer be active. The “16-week only” recommendation applies more to an older kitten or adult cat whose history is unknown; in that case, the single vaccine is adequate. For a more detailed explanation, see

  7. Brock on April 6, 2015 at 2:10 pm

    My vet said I need to vaccinate distemper for my newly adopted cat with modified live virus, once , then again at 3weeks.
    You are saying once is enough?

    How do I explain this to her? FYI my cat is estimated at one year and a half years of age.
    Thank you

    • adminjr on April 7, 2015 at 10:08 am

      Brock, I asked Dr. Hofve and she said, “If she is over 16 weeks of age, she only needs one vaccine to provide lifetime immunity, according to Dr. Ron Schultz.”

      You can watch Dr. Shultz’s videos at I think what you want is in the fourth video of his series with Dr. Becker.

    • Freya on February 15, 2016 at 8:16 pm

      Recently three (2 males and 1 female)three month old kittens were taken to a Veterinary clinic to be sterilized.
      These kittens went from the home where they had been since birth and living with their three siblings. Several days days after returning home,the female kitten’s operation site appeared infectd.She was returned to the Vet’s where she was found to to have all three of the virus’contained in the F3(core)vaccine.(Calici,herpes,feline parvo).She quickly lost her battle and passed away.A second kitten is fighting for his life and the third will survive.
      These kittens have never been away from their home environment. The Veterinary clinic being their very first outing. Their siblings who had stayed at home have remained disease free.
      So,how did they acquire these diseases?

      • adminjr on February 16, 2016 at 2:02 pm

        Freya, veterinary clinics, like hospitals, are dangerous places, even when they try to keep it clean. Diseased animals are one culprit. Also, live virus vaccines can cause the disease they are meant to prevent. Sorry for your losses.

  8. Retos para los cuidadores: gatito | Gato Gatito on July 6, 2014 at 10:02 am

    […] embargo, en el sitio de la vacunación, Truth4Pets, el Dr. Jean Hofve discute la relación entre el FVRCP vacuna contra la enfermedad y de riñón, una de las afecciones más comunes encontradas en los gatos. Ella cita el estudio en la Universidad […]

  9. Défis pour les soignants de kitty | Chat Minou on July 6, 2014 at 9:36 am

    […] Toutefois, sur le site de la vaccination, Truth4Pets, Dr Jean Hofve traite de la relation entre le FVRCP vaccins et les maladies rénales, un aux affections plus courantes trouvées chez les chats. Elle cite l’étude à la Colorado […]

  10. Challenges for kitty caregivers | ExclusivelyCats Blog on February 20, 2014 at 4:50 pm

    […] However, on the vaccination site, Truth4Pets, Dr. Jean Hofve discusses the relationship between the FVRCP vaccine and kidney disease, one of the most common afflictions found in cats. She cites the study at Colorado State University, […]

  11. MacKenzie on October 5, 2012 at 5:33 pm

    What about the intranasal vaccine? The study says it doesn’t cause kidney inflammation.

    • Ariella on November 27, 2012 at 12:45 pm

      I am interested in learning about the same thing. According to Dr. Michael Lappin, “parenteral administration of FVRCP vaccines induces a statistically greater magnitude of antibody response to CRFK proteins than intranasal administration of a FVRCP vaccine.” (“Update on FVRCP Vaccine Issues.” Retrieved at Lappin goes on to suggest that this is attributable to CRFK cells being unable to pass through the mucosal lining of the nose/mouth. I have been looking for follow-up studies, but I have not come across any. It appears that this study was conducted in 2004. Dr. Hofve, do you know of any additional studies or resources that have since addressed this issue? Thank you for your time!

      • admin-jhofve on November 27, 2012 at 2:01 pm

        His work is ongoing. Subsequent publications include:

        Mike has never been willing to come out and say that the panleuk vaccine *causes* CRF, but there’s enough evidence for *me* to say it…I don’t have an academic position and reputation to defend. His most recent work is directed toward getting away from injectable vaccines, since the intranasal form does not trigger the formation of antibodies to kidney proteins. And indeed that makes more sense, since that is the normal route of infection and induces a very fast IgA response that injectable vaccines fail to accomplish. By-passing the normal host defenses always seemed to me to be a bad idea!

        You can keep track of any new publications at Just search for “Lappin MR panleukopenia.” However, publication often lags the actual research by many months (or longer). Or just give him a call at Colorado State University, he’s a heck of a nice guy, adores cats, and I’m sure he’d be happy to answer your questions. (You can tell him I said so!)

  12. priya gehm on September 16, 2012 at 12:13 pm

    Dear Dr. Jean,

    How do you know that one injection won’t cause lifelong increased antibodies to renal proteins? That would be my assumption. If one shot can immunize for life, couldn’t one shot cause CRF over time?

    Are any distemper vaccines grown on cells that are not cat cells or similiar?

    Thank you so much!

    • adminjr on September 17, 2012 at 6:30 am

      Priya, I asked your question of Dr. Hofve and here’s her response: A single distemper vaccine will cause white blood cells (B cells) to create antibodies to the distemper virus and cat kidney cells (among many other things). Those antibodies reach their effective peak about 3 weeks after vaccination. However, the body does not continue to make antibodies after the virus is dealt with; so active inflammation is not perpetuated. Some kidney cells are probably killed in the process, but the kidneys have enormous reserve capacity. Kidney disease isn’t even detectable until almost 75% of kidney cells have been destroyed.

      After vaccination or infection, antibody-producing B cells go on to become “memory” cells that quietly sit in the lymph tissue unless and until they see the distemper virus again. If the distemper virus (wild or vaccine) comes around again, those memory cells will quickly begin producing new antibodies, and those antibodies will participate in a new round of inflammation. That is how lifelong immunity is created. Instead of taking weeks weeks to get antibody production up to speed, the immune system responds very rapidly, and the disease is defeated.

      If the memory cells are *not* triggered again, no new antibodies will be produced, so no new inflammation will be created.

      It is *repeated* boosters that stimulate antibody production again and again, and keep rekindling the inflammation and killing more kidney cells, that is the primary danger.

      I do not know of any feline distemper vaccines that are not produced on feline kidney cells, but technology is changing all the time. Your veterinary clinic can tell you what specific vaccines they use, and they (or you) can contact the company to find out the most current information.

Please comment:

Your email address will not be published. Required fields are marked *

Subjects of Interest

Subscribe to Truth4Pets

rss By RSS Feed

By E-mail

Follow @Truth4Pets

Facebook: Pet Vaccine Reactions