Panleukopenia

What is it?

Over the years feline panleukopenia has been known by a variety of names:  FP, feline distemper, infectious enteritis, cat fever, cat typhoid, and several others.

Panleukopenia is a highly contagious virus disease that occurs wherever there are cats. Cats at any age may be stricken. Young kittens, sick cats, and indoor cats that have not been given boosters recently are most susceptible; older cats are more likely to have acquired an immunity and, therefore, are infected less frequently.

Kittens less than 16 weeks of age may die at a rate of about 75%, and others at a rate of 50%.

Urban areas are most likely to see outbreaks of panleukopenia during the warmer months. The virus has appeared in all parts of the United States and most countries of the world.

Kennels, pet shops, humane shelters, and other areas where groups of cats are quartered appear to be the main reservoirs of panleukopenia today.

Dogs are not susceptible to feline panleukopenia. Canine distemper is a different disease caused by another virus of the Parvovirus family. Neither disease is transmissible to man.

What does it do?

The word "panleukopenia" means a decrease in the number of all of the white blood cells. The feline disease causes the white blood cell count to fall far below normal. Since white blood cells are important in defending a cat against infections and disease, this makes the cat very vulnerable to other infections. In addition to causing a low white blood cell count, this disease also causes severe damage to the lining of the stomach and intestines. After exposure to the virus, many of the cat's cells are destroyed. This cell loss makes the cat more susceptible to other complications and bacterial infections.

The panleukopenia virus is passed from cat to cat by direct contact. Infection occurs when contact is made with the blood, urine, fecal material, nasal secretions, and even fleas of infected cats. In most cases, recovered cats do not transmit the infection.

A healthy cat can also become infected without coming in direct contact with an infected cat. Bedding, cages, food dishes, and the hands or clothing of handlers may harbor and transmit the virus.

The panleukopenia virus is very stable. It is resistant to many chemicals and may remain infectious at room temperature for as long as one year. Short of raising a cat in total isolation, it is nearly impossible to prevent exposure.

Panleukopenia is a complex disease. It can vary in severity from very mild to extreme. The many signs are not always typical and many owners may even believe that their cat has been poisoned or has swallowed a foreign object. Because of this fact, treatment may be delayed or neglected.

The incubation period from infection until clinical signs develop is typically 3 to 5 days, seldom longer than a week.

How can you tell if a cat has panleukopenia?

The first signs a owner might notice are generalized depression, loss of appetite, high fever, lethargy, vomiting, dehydration, and hanging over the water dish. The course of the disease may be short and explosive. Advanced cases, when discovered, may cause death within hours. Normally, the sickness may go on for three or four days after the first elevation of body temperature. Sometimes affected cats present as a sudden death, indeed cats which "go off to die somewhere" may be suffering from this condition.

If a pregnant queen is infected with panleukopenia, the brain of her unborn kittens may be affected. The part of the brain which becomes damaged is the part that controls balance, so that from about 2 weeks of age, when kittens first become really mobile, they can be seen to have a wobbly gait. At weaning they have difficulty feeding because their heads bob up and down.

 There are some variations, but typically cats experience:

     • very deep depression or listlessness which may progress to collapse

     • vomiting and diarrhea are frequent: the diarrhea may be watery and bloody

     • hair coat quickly becomes dull and rough

     • skin loses it elasticity due to dehydration

Often cats with panleukopenia have other infections because their immune system is compromised. Fever will fluctuate during the illness and abruptly fall to subnormal levels shortly before death. Other signs in later stages may be diarrhea, anemia, and persistent vomiting.

Panleukopenia is so prevalent and the signs so varied that any sick cat should be taken to a veterinarian for a definite diagnosis.

If you want to know if panleukopenia is present in your premises but none of your cats are presently sick, test them for antibodies against the virus. The levels of antibodies (ie. their antibody titres) are much higher than they would be from just having been vaccinated, so testing healthy in-contact cats can reveal the presence of panleukopenia in the environment.

Can an infected cat be treated?

As for most viral diseases, there is no specific treatment that kills the virus. However, the secondary infections that usually occur are treated with antibiotics. Dehydration and shock are life-threatening components of panleukopenia; intravenous fluid therapy and intense nursing is critical to control them. Drugs are also given to control vomiting and diarrhea. Some cats do not recover from this disease, but many will if aggressive supportive therapy is given.

The veterinarian will attempt to combat extreme dehydration, provide nutrients, and prevent secondary infection with antibiotics. If the cat survives for 48 hours, its chances for recovery are much better. Pregnant females that contract the disease, even in its mildest form, may give birth to kittens with severe brain damage.

Strict isolation is essential. The area where the cat is kept should be warm, free of drafts and very clean. Plenty of "tender loving care" is very important. Cats may lose the will to live; so frequent petting, hand feeding, the cautious use of heating pads, and good nursing care by the owner is essential.

The prognosis for kittens less than 8 weeks old is poor. Older cats have greater chance of survival if adequate treatment is provided early in the course of the disease.

Other cats that may have been in close association with the infected animal should be carefully examined.

Do panleukopenia carrier cats exist?

No, the virus passes very quickly through the cat, most cats only shed it for just a couple of days.

Are there any long-term consequences for the cat?

No. Once the virus runs its course, the lining of the stomach and intestines recovers quickly without scarring. In addition, the bone marrow produces new white blood cells to replace those that were lost. The cat recovers completely.

What about prevention and protection?

Panleukopenia is controlled in several ways. Cats that survive a natural infection usually develop sufficient, active immunity to protect them for the rest of their lives. Mild cases may go unnoticed and also produce immunity.

It is also possible for kittens to receive immunity from their mother through the transfer of antibody. This passive immunity from the mother is temporary and its effectiveness varies in proportion to the level of antibody in the mother's body. The immunity diminishes rapidly and is not considered effective after 12 weeks of age.

Vaccines offer the safest protection. Most vaccines are made from live viruses treated to destroy their ability to cause disease. They stimulate the cat's body to produce protective antibodies against the virus to prevent infection by natural, disease causing viruses. The vaccines are very effective but are preventive, not curative. They must be administered before the cat is exposed and infected to be effective. Most young kittens receive their first vaccination between 6 and 12 weeks of age, or as soon as they are taken from their mother. Vaccination must be repeated annually as a booster to maintain effective immunity.

Specific vaccination schedules vary depending on many factors, such as the disease incidence in the area, age and health of the cat, etc.

The pet owner should consult a veterinarian for advice on the correct schedule for each cat.

Is there any point in revaccinating the adult cats after a panoleukopenia outbreak?

Probably not. Most will already have protective high antibody titres.

How do I disinfect my house?

Since the panleukopenia virus is difficult to kill, most disinfectants are not effective. We recommend 1 cup of chlorine bleach per gallon of water as the best way to kill the virus. Be careful not to bleach your furniture, carpet or other flooring material with it.