Feline Panleukopenia (Feline Distemper)

Nursing Kittens Kneading Mother Cat. photo © Getty Images / John P Kelly

Feline Panleukopenia (Feline Panleuk), as it is often called, is an extremely contagious virus of the parvovirus group, with a high mortality rate, which often targets kittens. Areas with large populations of unvaccinated cats, such as feral colonies or homes of "cat collectors," are particularly susceptible to panleuk outbreaks.

How is Feline Panleukopenia Transmitted?:

The feline panleuk virus (FVP) is extremely hardy and may survive for months, and even years.

It is easily transmitted through contact, either cat-to-cat or by human-to-cat:

  • Shared food and water bowls, litter pans, bedding
  • Mutual grooming
  • Fleas, during the active stage
  • In utero, from an infected queen
  • Human handling can transfer the FVP virus from one cat to another, by contact through hands, clothing, and shoes.

What Are the Symptoms of Feline Panleukopenia?

The initial symptoms are also found in many other diseases, and always indicate the need for a veterinary examination.

  • Vomiting
  • Diarrhea
  • Depression
  • Disinterest in food and water
  • Appearance of the "third eyelid," or haw, in the inner corner of the eye
  • Lack of grooming, evidenced by dull, rough coat
  • Evidence of abdominal pain
  • A "hunched over" postural appearance

How is Panleukopenia Diagnosed and Treated?

A tentative diagnosis may be made by the history of symptoms and clinical signs such as fever or a drop in the white blood cell count. The latter symptoms may vary from cat to cat, and depending on the stage of the infection.

A finding of antibodies to the virus in the blood will confirm the diagnosis.

Treatment involves alleviating vomiting and diarrhea, to prevent subsequent dehydration, along with steps to prevent secondary bacterial infections, until the cat's natural immune system takes over.

Cerebellar Hypoplasia, A Serious Side Effect

Cerebellar Hypoplasia, also known as Cerebral Hypoplasia, may be contracted by kittens in their mother's uterus before birth.

This can be caused by the mother cat contracting panleukopenia, or receiving the panleukopenia vaccines (included in core vaccines) during her pregnancy.  Cerebellar Hypoplasia en utero, can also be caused by injury or poisoning.  A sure sign of CH in the kittens will be "bobbly" heads when attempting to nurse, or spastic movements when later trying to walk. 

Prevention of Feline Panleukopenia:

When born to a queen with FPV antibodies, kittens will have a natural immunity for the first eight to ten weeks. After that period, vaccinations should be started. The FPV vaccine is often combined with "3-way" shots, which also include protection against feline herpes virus 1 (FSV1), and feline calicivirus (FCV). Kittens receive a series of follow-up vaccines, and all adult cats should be vaccinated every one to three years for FCV, depending on the kind of vaccine used.

According to the Veterinary Medicine website, "Calicivirus infections are almost always found in cats with chronic inflammation of the mouth and gums (stomatitis/gingivitis). However, it is unclear what role, if any, calicivirus has in the development of this disease."

The FPV vaccine is not recommended for kittens under eight weeks of age, since their natural immunity may interfere with the efficacy of the FPV vaccine.

An FPV antiserum can be used to immunize kittens under eight weeks, which have been exposed to the FPV virus, and also for older, unprotected cats who have been exposed.

Preventing Further Outbreaks of Panleuk:

Since the FPV virus is so hardy and can persist in the environment for months or years, a thorough disinfection of the entire premises needs to be made after an outbreak of feline panleuk in a home shared by cats. The only disinfectant presently acknowledged is a dilute bleach solution, of 1:9 (one part bleach to nine parts water.)

Although feline panleukopenia is considered a "dread disease" of cats, with routine vaccinations, isolation of cats new to the household until they have been tested and vaccinated, and routine sanitary precautions, the average multi-cat household should remain safe from this disease.


Much of the information in this article was found by reading the Cornell Book of Cats, a book I highly recommend as a veterinary resource for concerned cat owners.