Feline Infectious Peritonitis (FIP)

By Kari Winters

For anyone who’s dealt with it, the thought of FIP brings stark fear. FIP is a disease that breaks all the rules. Rescuers have to deal with it frequently and they know that it’s hard to diagnose and that the diagnosis is a usually a death sentence.

Recently, I was fortunate enough to be able to attend the FIP Symposium at the Western Veterinarian Conference in Las Vegas. The speakers were Dr. Melissa Kennedy, who specializes in researching viruses at the University Dr. Susan Little, a renowned lecturer, Dr. Danielle Gunn-Moore from the U.K. and Dr. Niels Pedersen from UC Davis who is one of the leading researchers in the field. The information in this article comes from that symposium.

Feline Infectious Peritonitis (FIP) comes in two forms: Wet (effusive) and dry (non-effusive). The experts all agree, and emphasized that there is no diagnostic test for FIP. There may be some abnormal lab values that make a veterinarian suspicious of FIP, but the diagnosis is rarely firm until the cat or kitten dies. Often the cat or kitten presents to the veterinarian as “just not being right.” The symptoms, particularly for the dry form can be very vague. There are some symptoms, though, that should cause suspicion that a cat may have FIP. These include:

• age of the cat (usually less than 2 years or older than 13 years)
• fever that comes and goes and is not responsive to antibiotics
• loss of appetite
• weight loss
• low energy
• neurological signs such as seizures or difficulty with balance
• urinary incontinence, which is rare in cats and is almost always a sign of FIP
• a very large abdomen filled with fluid (in the wet form only)

Symptoms may occur suddenly or may happen so gradually that by the time they are noticeable, they are very severe. Cats with FIP usually have had a recent stressor such as illness, surgery, moving to a new place, or a recent addition to the family such as a baby or a new cat or dog. It has been noted that many cats with FIP are declawed, so although there’s no research on this, it is thought that declawing is a bigger stress to cats than many other surgeries.

So how do cats get FIP? Recent advances tell us that there's a genetic component as well as an environmental one. FIP is a mutation of a virus called Feline Enteric Corona Virus (FECV) that is shed by some cats in their feces. It can also be shed through saliva, though this is rare. FECV and FIP are not communicable to humans. Many cats have FECV but never show signs of illness. If a cat's immune system and genetics are such that they can be exposed to FECV without converting it to FIP, they don't ever get the disease. It's important to note that once a kitten has FIP it doesn't have to be isolated as it is no longer contagious in this form. In fact, the experts believe that it may be more stressful to the kitten to isolate it. Older cats who get FIP are cats who have been carrying the FECV virus all along, but whose immune systems are now no longer able to handle it. Many of the experts believe that kittens should be kept away from adult cats until they are 6 months old so that they have no chance of being exposed too FECV while their immune systems are still developing.

It used to be that most cases of FIP were the wet form and in this form, kittens usually only live a few days to a few weeks. Now, however, veterinarians are seeing more of the dry form, which, according to Dr. Pedersen, means that cats are developing more immunity. In the dry form, some cats survive several weeks to over a year. Although there is no cure for FIP, the diagnosis itself is not a reason to euthanize a cat or kitten. If euthanasia is necessary, it is because the cat no longer has a good quality of life.

To try to prevent FIP, it is important to keep the environment very clean. Litter should be scooped twice daily and then thrown out after a week. The box and litter scooper should be cleaned with a disinfectant before new litter is put in. Food and water should be changed daily and the bowls should also be disinfected weekly. For rescue groups with kennel facilities, the same bowls should be kept with the same group of cats or kittens. New cats or kittens should be isolated for a minimum of 21 days. Kittens should then be kept separate from adult cats (as mentioned earlier) until they’re at least 6 months of age.

One of the many tragedies of FIP is that often the people affected are those who’ve lost a beloved older cat and then adopt a kitten. After the adoption, the kitten becomes sick and FIP may be suspected. This is frustrating to both rescuers and adopters as the rescuers see the kitten as healthy and ready for adoption. This is because rehoming can be a great stress for some cats and kittens. When the kitten dies, the adopter who so recently dealt with the death of a beloved pet must now deal with death again. When the panel was asked about this, they said that potential adopters might want to adopt a cat 1-2 years of age so as to try to avoid this. Cats of any age bond equally well with new families.

While there's still no news of a cure, more information is now known about this disease so that hopefully it can become less prevalent.

Kari Winters is a Registered Nurse, member of Cat Writers' Association, and volunteers with Siamese rescue. She can be reached through her website www.shelterpetsink.com. This article was first published in The Pet Press in Los Angeles, CA.

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