Panleukopenia Virus (Feline)

Panleukopenia is a highly contagious virus of the family parvoviridae. It infects primarily very young or immune deficient cats and is potentially fatal. Clinical signs often include depression and vomiting and diarrhea leading to dehydration. The name stems from the common finding of low white blood cell counts in animals infected with the virus. Appropriate vaccination is highly effective at preventing disease.

Common name: Feline distemper, Feline viral enteritis, Fading kitten syndrome
Scientific name: Feline panleukopenia virus

Diagnosis

Signalment
Primarily young or unvaccinated cats. Cats with impaired immune systems are also at risk.

Incidence/prevalence
Due to the existence of an effective vaccine, the incidence is uncommon. However, documented infections still exist, particularly in environments with large numbers of cats.

Geographic distribution
There is a worldwide distribution of feline panleukopenia virus.

Clinical signs (primary, most to least frequent, scientific term, synonyms)
Vomiting, Diarrhea, Decreased white blood cell count (panleukopenia), Fever.

Clinical signs (secondary, most to least frequent, scientific term, synonyms) Weight loss, Systemic infection (sepsis), Death.

Cause (scientific, common term)
Feline parvovirus.

Organ system affected (most to least affected)
Gastrointestinal, Lymphatic, Hematopoietic (bone marrow).

Diagnostic Tests
CBC (complete blood count), Fecal Parvo Elisa Tests (cross-reacts with canine parvovirus antibodies), Virus isolation in tissue samples, Serology.

Differential Diagnosis
Gastrointestinal foreign body, Pancreatitis, Feline leukemia virus, Salmonella.

Overview

Feline panleukopenia virus is a member of the Parvovirus family. Hosts for the virus include cats, raccoons and mink. The causative virus is highly contagious and can persist in the environment for one year at room temperature. The virus is harbored in locations where groups of cats are kept such as pet stores, kennels and humane shelters. Urban areas are more likely to see outbreaks during warmer months. Viral transmission occurs readily through contact with blood, urine, feces, nasal secretions and even fleas from infected cats. Infection usually occurs when the virus enters the body through the nose or mouth. The virus replicates in rapidly dividing cells found in lymph nodes, intestines and bone marrow. Feline panleukopenia virus suppresses the development of all types of white blood cells (hence the name pan/leuko/penia), thereby inhibiting the immune system. Mortality rates in unvaccinated kittens less than 16 weeks of age may reach 75% or higher. Kittens under 8 weeks of age have a poor prognosis for recovery.

Treatment

Home Care
Rarely are symptomatic cats able to be managed properly at home. If minor clinical signs appear, oral medications may be needed to prevent vomiting and secondary bacterial infection.

Professional Care
The American Association of Feline Practitioners recommends vacation of kittens against feline panleukopenia virus every 3-4 weeks until at least 12 weeks old and then once at 12 months followed by boosters every three years. Alternatively, blood antibody titers may be obtained annually to establish evidence of adequate immunity. An intranasal vaccine is available but its benefit over the injectable form is debatable. For infected kittens and cats, there is no cure for the virus. Hospital care is required until the pet is able to take in and absorb nutrients orally. In kittens there is little chance of survival without hospitalization. Pregnant queens should not be vaccinated with modified live virus vaccines as cerebellar hypoplasia can develop in the kittens.

Action
Treatment is supportive care and similar to most other types of severe gastroenteritis. This includes intravenous fluids, antiemetics and antibiotics to prevent secondary bacterial infection. Blood products may be given to treat for low protein or anemia. Intravenous fluids and medications are used until oral intake resumes. There are anecdotal reports of human anti-influenza medications reducing the severity of clinical signs, however dosages in cats are not yet established and their use is strictly off-label.

Outcome
The outcome is variable depending on age, health and vaccination status of the patient. Kittens under 8 weeks of age are least likely to recover, even with aggressive supportive care. Adults or fully vaccinated cats have a better prognosis for full recovery. Kittens who survive an infection will shed the virus for up to 6 weeks after recovery. They will also develop lifetime immunity to the virus. This is a potentially devastating disease, which is easily prevented by through proper vaccination.

Recommended Treatment
Panleukopenia is a life-threatening condition. See your veterinarian immediately for proper diagnosis and treatment of suspected Panleukoenia.

References/Additional Readings
Kahn, DE. Feline Panleukopenia. In: Barlough, JE, ed. Manual of Small Animal

Infectious Diseases, 1st Ed. New York: Churchill Livingstone, Inc. 1988; 1-5.

American Veterinary Medical Association Website, Feline Panleukopenia‚ referenced December 10th, 2007. www.avma.org/communications/brochures/panleukopenia/panleukopenia_brochu...

Author
Patricia Wagner, DVM

Editor
Steven Hansen, DVM, MS, MBA, DABVT, DABT