Published by: Ingrid King. Last Updated on: October 31, 2022 by Crystal Uys
There is no question that vaccines protect against disease – but they also present considerable risk. Sadly, far too many cats are still being over-vaccinated because too many veterinarians, and cat guardians, still think annual “shots” are necessary. Vaccines are implicated in triggering various immune-mediated and other chronic disorders (vaccinosis). Vaccines are also implicated in the high incidence of vaccine-induced sarcomas in cats. The incidence of these tumors ranges from 1 in 1000 to 1 in 10,000 cats. They can develop as quickly as 4 weeks or as late as 10 years post vaccination.
There is some compelling evidence coming from a study conducted at The Center for Companion Animal Studies at Colorado State University that shows that the common FVRCP (feline viral rhinotracheitis, calicivirus and paneleukopenia) vaccine may cause long-term damage to cats’ kidneys that increases with every booster.
Holistic veterinarian Dr. Jean Hofve reported on her blog, Little Big Cat, that the study showed 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, a kidney disorder in which the spaces between the kidney tubules become inflamed. If this type of inflammation remains chronic, it can eventually lead to kidney failure.
Interestingly, the study showed a difference depending on whether the vaccine was delivered by injection, or intranasal. Cats who received the FVRCP vaccines by injection had higher levels of circulating antibodies to these antigens than cats who were administered the intranasal FVRCP vaccine.
Similar antibodies have been implicated in the development of renal disease in humans. 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.
This information should give cat guardians pause before agreeing to have their cats’ distemper vaccines boosted. The American Association of Feline Practitioners currently recommends FVRCP boosters every three years in their Feline Vaccination Guidelines. However, immunity studies, such as the research done by Ronald Schultz, professor and chair of pathological sciences at the University of Wisconsin Madison School of Veterinary Medicine, have shown that immunity for some vaccines lasts even longer than that, anywhere from 7 to 15 years.
Dr. Hofve recommends not vaccinating your adult cat for distemper, and many holistic veterinarians agree with her. “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,” writes Dr. Hofve on Little Big Cat. “There is no benefit, and substantial risk, to repeated distemper vaccines in adult cats.”
If your cat is still receiving her FVRCP booster every three years, or worse, every year, I urge you to discuss this issue with your veterinarian, or to find one who practices individualized feline medicine rather than taking a one size fits all approach.
About the author
Ingrid King is an award-winning author, former veterinary hospital manager, and veterinary journalist who is passionate about cats.