Feline panleukopenia

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Feline panleukopenia (also called feline distemper) is a highly contagious, potentially fatal disease of cats caused by the feline panleukopenia virus (FPV, also called feline parvovirus). Kittens are most severely affected. Despite the names used to describe feline panleukopenia, the disease is not to be confused with canine distemper or canine parvovirus infection, which are caused by different viruses.

FPV attacks cells that are rapidly growing and dividing, such as those in the lymph nodes, bone marrow, intestines, and developing fetuses. The name "panleukopenia" stems from the damaging effect that FPV has on white blood cells (leukocytes), which the body needs to fight off infection.

Fortunately, there are highly effective vaccines available to help protect cats against feline panleukopenia.

Which cats are at risk of feline panleukopenia?

Because FPV is everywhere in the environment, almost all kittens and cats are exposed to it at some point in their lives. Although cats of any age may catch the virus, young kittens, sick cats, and unvaccinated cats are most likely to become ill. Certain cat groups also are more susceptible, such as those in pet shops, animal shelters, kennels, or boarding facilities, and unvaccinated feral cat colonies.

How is feline panleukopenia spread?

Infected cats can pass FPV in their feces (stool) and body fluids like urine and nasal secretions. Susceptible cats may become infected when they contact these substances, the infected cats themselves, or even fleas from infected cats. Infected, pregnant cats can also pass the virus to their unborn kittens.

Other possible sources of infection are virus-contaminated items like these:

  • Bedding
  • Litter boxes
  • Cages
  • Food and water bowls
  • Toys
  • Hands or clothing of people who have handled infected cats

What are the signs of feline panleukopenia?

Most cats with FPV infection have no signs at all and appear normal. Cats that do become ill—most often those younger than a year old—may have the following:

  • Diarrhea
  • Vomiting
  • Fever
  • Depression/lethargy
  • Loss of appetite
  • Dehydration (may appear as sunken eyes or dry gums)
  • Painful belly

Affected cats—especially kittens—also may suddenly die. If your cat shows any of the above signs, immediately contact your veterinarian. And, to keep the disease from spreading, keep your cat away from other cats.

Because FPV can significantly decrease the body's ability to fight infection, cats also may develop other infections, like respiratory disease, and have signs caused by those infections, too.

Illness in cats that survive FPV infection typically lasts no more than a week. Kittens younger than five months old are at greatest risk of death. Surviving kittens infected before or shortly after birth may suffer brain damage, causing incoordination and tremors when moving, or seizures. Blindness also is possible.

How is feline panleukopenia diagnosed and treated?

Your veterinarian may suspect your cat has feline panleukopenia based on the signs your cat is showing, whether or not your cat's vaccines are current, whether your cat has been exposed to other cats (especially cats that might not have been vaccinated), and other factors. Bloodwork typically will be advised to measure your cat's white blood cells, identify any abnormalities, and help with a diagnosis. Other tests may be recommended to confirm that the virus is present.

Prevention is vital to your cat's health. It all starts with vaccination.

There's no specific treatment for feline panleukopenia, so care usually focuses on supporting affected cats with fluids, nutrients, and other essential needs until they improve. This typically involves isolation from other cats, whether within the veterinary hospital or at home.

Severely ill cats are at risk of life-threatening dehydration and shock, and need intensive care and monitoring as soon as possible. This type of care often includes intravenous (IV) fluid therapy, nutritional support, pain and/or anti-vomiting medications, and—for cats with bacterial infections caused by immune suppression—antibiotics. Cats with anemia and/or protein loss also may need a transfusion.

Whether a cat recovers depends on a variety of factors, such as their age and general health status, the severity of their illness, and how quickly they receive veterinary attention. Generally, the earlier a cat receives care, the better the chance of a good outcome.

How can feline panleukopenia be prevented?

Prevention is vital to your cat's health. It all starts with vaccination.

Young kittens are especially susceptible to FPV infection. If a mother cat has antibodies against the virus, then she may share those antibodies with her newborn kittens through her milk. This mother-provided immunity provides important protection as kittens begin their lives—but this protection soon declines. This means that it's important to vaccinate kittens. However, if kittens are vaccinated before their mother-provided immunity has declined to a certain level, that immunity can interfere with the kittens' response to vaccination. So occasionally even vaccinated kittens may become infected and ill.

A series of vaccinations is recommended to provide the best protection against FPV during the first few months of life. The FPV vaccine is included in a combination vaccine (often abbreviated FVRCP) that also protects cats against two other common viruses: feline herpesvirus 1 and feline calicivirus. This vaccine is considered a "core" vaccine and is recommended for all cats—including cats that don't normally go outdoors or interact with other cats.

Kittens younger than 16 weeks should receive their first dose no earlier than 6 weeks of age (typically at 6 to 8 weeks), and then be revaccinated every 3 to 4 weeks until 16 to 20 weeks of age. Cats older than 16 weeks that have never been vaccinated or have an unknown history should receive one or two doses, with the second dose given 3 to 4 weeks after the first.

To maintain protection, a booster dose of the combination vaccine is recommended at 6 months of age, with additional boosters every year (intranasal vaccine) or every 3 years (injectable vaccine) afterward. If your adult cat hasn't been vaccinated yet, or is overdue for some vaccinations, it's not too late. Ask your veterinarian about a recommended vaccination program based on your cat's age and needs.

In addition to vaccination, these measures can help protect your cat and others from feline panleukopenia and other infectious agents:

  • Avoid contact with known infected cats and their premises.
  • Keep your cat indoors to reduce the risk of exposure to potentially infected cats.
  • Wash or sanitize your hands after handling other cats, especially if they appear sick.
  • Avoid sharing toys, food bowls, and other items between your cat and those of unknown health or vaccination status.
  • When bringing a new cat or kitten into a home where other cats live, keep the new animal separated until your veterinarian has had a chance to examine the newcomer and they've received their necessary vaccines.
  • Keep sick cats away from other cats, and disinfect possible FPV-contaminated surfaces with a 1:32 dilution of household bleach (1/2 cup of bleach in 1 gallon of water) applied for at least 10 minutes.

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Also in Spanish: Panleucopenia felina