Tail vaccination may lead to better cancer treatment in cats

University of Florida College of Veterinary Medicine professor Julie Levy, DVM, PhD, led a study concluding a cat's tail is an effective vaccination injection site. Veterinary student Cleon Hendricks participated in the tail vaccination study through the Merial Veterinary Scholars program. Photo courtesy of Sarah Carey

When administering vaccinations in cats, most veterinarians give injections below the elbow or knee joint in the leg as recommended by the American Association of Feline Practitioners (AAFP). However, a report published in October by the Journal of Feline Medicine and Surgery suggests that the tip of a cat’s tail appears to be as effective as vaccines at traditional sites.

Julie Levy, DVM, PhD, Maddie’s Professor of Shelter Medicine at the University of Florida College of Veterinary Medicine, believes a change in vaccination protocol could improve cancer treatment in cats. “One to 10 cats out of every 10,000 vaccinated against infectious diseases develop cancer at the vaccine injection site,” Levy says in a release from the university. “It’s still important to vaccinate because death from these infections is much more common than the cancer, but unfortunately this complication is one that does affect thousands of cats each year.”

Levy and the team of infectious disease and vaccinology experts report tail vaccination would make surgical treatment of any cancer occurring near the site much easier, less invasive and less disfiguring for the animal, which could encourage more owners to treat the disease in their pet when it occurs.“Many cat owners elect not to pursue the most effective treatment—radical surgery of the tumor—because excision of tumors in the limbs and torso is often disfiguring, painful and expensive,” Levy said. She says current AAFP protocol is based on the understanding that amputation of a limb is the most effective treatment for cancer that occurs near vaccine injection sites.

“If vaccinations on the end of the tail become a widely adopted practice, then amputating the tail is a much easier and less traumatic procedure, which will hopefully result in a much greater potential to cure this disease,” Julius Liptak, BVSC, a surgery specialist and a founding fellow in surgical oncology with the American College of Veterinary Surgeons states in the release.

The study found the tail was noted as the top preferred injection site after polling veterinary oncologists around the world asked to consider only surgical treatment of sarcomas that might develop at those site. A subsequent trial enrolled 60 cats participating in the UF Operation Catnip trap-neuter-return program. Researchers required participating cats to be tame, outwardly healthy, to have a full-length tail and brought by a caregiver committed to returning the cat in one or two months for further evaluation.

The study concluded participants tolerated tail vaccination at least as well as the currently recommended injection site in the hind leg, paving the way for what Levy and others hope will be an alternative injection site for cats.

“Firstly, it is important that vaccinations in the tail are effective in providing the necessary immunity against infectious and communicable diseases,” Liptak says. “Secondly, vaccinations in the tail are easy to perform and well tolerated by cats, which will hopefully mean that general practitioners will be willing to change their vaccination protocols and try this new location.”

The study was supported by grants from Maddie’s Fund, the Merial Veterinary Scholars Program and the Harold H. Morris Trust Fund for Research in Diseases of Small Animals.