If you don't recall your cat getting a shot specifically for distemper, that's because it's generally combined with other vaccines in what's called the FVRCP shot. Those letters stand for feline viral rhinotracheitis, caused by the herpesvirus; calicivirus; and panleukopenia, the formal name for distemper.
Besides distemper, feline panleukopenia is also known as feline enteritis. Because of widespread vaccination, it's not seen much these days. That's a good thing, because cats who come down with it often die. It's caused by a parvovirus that wreaks havoc in puppies, and kittens infected with distemper suffer a very high mortality rate. Extremely contagious, distemper manifests as loss of appetite, fever, vomiting and diarrhea and depression. Affected animals rapidly dehydrate. Internally, their intestines ulcerate while their infection-fighting white blood cells are suppressed by the virus. According to The Merck Veterinary Manual, infected kittens may die suddenly, with no warning.
Because babies are so vulnerable to distemper, your vet vaccinates your kitten with the FVRCP vaccine for the first time between the ages of 6 to 8 weeks, with another shot every three to four weeks until your kitten is 4 months old. If you find a stray cat or adopt a cat with an unknown vaccination history, the cat receives an initial shot, with two more shots three to four weeks apart.
Whether your now-grown cat received his first FVRCP shots as a kitten or an adult, he'll need a booster one year after the initial series and then another booster every three years. If your cat spends time outside or otherwise comes in contact with a lot of strange felines, your vet might recommend an annual booster. The FVRCP is considered a core vaccine, along with rabies shots, meaning it's recommended for all cats. Your vet gives the FVRCP injection in the right front leg. If your cat develops a rare vaccine-related cancer called fibrosarcoma at the injection site, the leg can be amputated to save his life. An intranasal vaccine is also available.
If you know or suspect your cat is pregnant, wait until after she's finished nursing the kittens before getting her a booster shot. She might miscarry if vaccinated while pregnant, or her kittens may develop cerebellar hypoplasia. This affects the part of the brain regulating movement. Affected kittens suffer from tremors, making normal movement impossible, and are generally euthanized. If your cat is sick, wait until he is well before scheduling his initial or booster shots.
- The Merck Veterinary Manual: Feline Panleukopenia: Introduction
- American Veterinary Medical Association: Feline Vaccines: Benefits and Risks
- Vetstreet: Feline Distemper (Panleukopenia) Virus Vaccine
- Mar Vista Animal Medical Center: Feline Distemper (Panleukopenia)
- University of California–Davis School of Veterinary Medicine: Canine and Feline Vaccination Guidelines
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