Feline Panleukopenia (Distemper): Signs, Treatment, Vaccine

By Tailwisp Editorial TeamUpdated October 20, 20264 min read

Feline panleukopenia is one of the most feared diseases in shelters and kitten litters. It spreads quickly, kills many kittens and persists in the environment for months. Yet it is almost entirely preventable with a vaccine, which is why vets call it a core vaccine and stress it so much.

What is it?

The disease is caused by feline parvovirus, which attacks cells that divide fast, such as those in the intestinal lining, bone marrow and, in unborn or newborn kittens, the cerebellum. The name panleukopenia means a low count of all white blood cells, since the virus destroys the bone marrow where they are made. With few white cells, the cat cannot fight infection, and intestinal damage allows bacteria into the blood.

How it spreads

The virus is shed in feces, urine, vomit and saliva. Cats catch it by contact with infected cats or contaminated places, bowls, bedding, hands and clothes. It survives for a year or more in the environment, resists many disinfectants and is hard to eliminate. Pregnant cats can pass it to their kittens. Outbreaks occur in shelters, rescues and multi-cat households.

Who is at risk

Unvaccinated kittens between about two and six months old are at highest risk, particularly when maternal antibodies fade. Unvaccinated adult cats and sick or stressed cats are also vulnerable. Cats that have completed their vaccination series have strong protection.

Signs

• Sudden fever and lethargy.
• Loss of appetite, and refusing water.
• Vomiting, often yellow or foamy.
• Severe, sometimes bloody, diarrhea.
• Dehydration and weight loss.
• Hunched posture, and abdominal pain.
• Hiding near the water bowl, with the head over the water but not drinking.
• Sudden death, in young kittens.
• Kittens infected before or just after birth may have poor coordination, tremors and wobbling because of damage to the cerebellum.

See cat emergency warning signs.

Diagnosis

The vet performs a physical exam and bloodwork, which shows a very low white cell count. A fecal test, similar to the one used for canine parvovirus, can detect virus, though results can be negative, and PCR tests may be used.

Treatment

There is no drug that kills the virus. Treatment aims to support the cat while its body fights, and to prevent secondary infection:

• Intravenous fluids and electrolytes.
• Anti-nausea drugs and pain relief.
• Antibiotics, to treat secondary infections.
• Nutritional support, including feeding tubes where needed.
• Isolation, in an intensive care unit.
• Sometimes plasma or blood transfusions, and other medication.

With intensive care, a good share of cats survive, and those that survive the first few days often recover and become immune for life. Without care, mortality is high, especially in young kittens.

What to do at home

If your cat is sick, call your vet before you come in, so they can isolate the cat and protect other patients. Keep it away from other cats. Wash your hands, and change clothes after handling.

Cleaning and disinfection

The virus resists many disinfectants. Use a dilute bleach solution, about one part bleach to thirty parts water, after thorough cleaning, with several minutes of contact time, on surfaces that tolerate it. Discard bedding, toys and items that cannot be disinfected. Keep unvaccinated cats away from the area for months. Ask your vet for advice. See cat-safe cleaning products for general guidance, and keep cats away from bleach while cleaning.

Vaccination

The panleukopenia vaccine is part of the core FVRCP vaccine. Kittens typically receive a series, starting at six to eight weeks, with boosters every three to four weeks until about sixteen weeks, then a booster at one year and every three years for most adult cats. See cat vaccination schedule and kitten first vet visit. Do not allow young kittens to mix with unvaccinated cats.

Adopting and fostering

Quarantine new cats and kittens, and ask for vaccination records. If you foster or find a stray kitten, take it to a vet promptly, and keep it separate. See what to do if you find a stray kitten.

Shelters, rescues and outbreaks

In shelters and rescues, panleukopenia can spread rapidly, so many follow strict protocols: vaccinating on intake, isolating new arrivals and cleaning with effective disinfectants. If you adopt a cat and it becomes sick within a few days, call your vet right away and mention where the cat came from. Report suspected cases to the shelter, since other animals may be at risk.

Protecting kittens in your home

Keep kittens indoors until they have completed their vaccinations, and avoid contact with cats of unknown vaccination status. Visitors who have handled other cats should wash their hands and change clothes. Do not let kittens use shared spaces with unknown animals. If you have lost a cat to panleukopenia, wait several months, and ask your vet about the right time, before bringing in an unvaccinated kitten, and make sure every new cat is fully vaccinated.

Cerebellar hypoplasia

Kittens infected in the womb or during the first weeks of life may be born with cerebellar hypoplasia, a condition in which the part of the brain that controls coordination is underdeveloped. These kittens wobble, tremble and fall, but they are not in pain, and the condition does not worsen. With a safe home, many live happy lives.

Outlook

Cats that survive the first several days often recover completely, and carry lifelong immunity. Early supportive care, quick isolation and strict hygiene are the keys to survival.

When to see a vet

See a vet immediately if a kitten or unvaccinated cat has vomiting, diarrhea or lethargy. Use the US vet directory to find a clinic.

This article is general educational information, not veterinary advice. Every cat is different. If your cat is unwell, or you are unsure about a symptom, diet change or medication, contact your veterinarian.