Over the years feline panleukopenia (FP) has been known by a variety of names; feline distemper, infectious enteritis, cat fever, cat typhoid, and several others.
FP 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.
Urban areas are most likely to see outbreaks of FP 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 FP today.
Dogs are not susceptible to feline panleukopenia. Canine distemper is a different disease caused by another virus. Neither disease is transmissible to man.
The first signs an 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.
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.
FP is so prevalent and the signs so varied that any sick cat should be taken to a veterinarian for a definite diagnosis.
The prognosis for kittens less than 8 weeks old is poor. Kittens less than 16 weeks of age may die at a rate of about 75%, and others at a rate of 50%. Older cats have greater chance of survival if adequate treatment is provided early in the course of the disease. Treatment is limited to supportive therapy to help the patient gain and retain sufficient strength to combat the virus with its own immune system. There are no antibiotics that can kill the virus.
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.
Other cats that may have been in close association with the infected animal should be carefully examined.
FP 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.