Science

Feline Infectious Peritonitis (FIP)

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In memory of Sully

Gray cat with Christmas tree
Sully died of FIP at the end of 2021

Feline Infectious Peritonitis (FIP) is a severe multi-organ-system viral disease that affects domestic cats as well as other felines [2, 5]. Until very recently, a diagnosis of FIP was a death sentence for a cat. It is still often fatal. However, knowledge is power. Knowing when to go to the vet and what your options are can save a life.

What Causes FIP?

FIP starts with an intestinal virus called feline enteric coronavirus (FeCV or sometimes FCoV). You can’t catch this coronavirus; only felines can [1, 4, 5, 9]. FeCV is very common among cats, especially in places where many cats live close together like shelters and catteries [1, 2, 5, 8]. Most cats infected with FeCV experience no symptoms, mild diarrhea, or mild respiratory illness before defeating the infection on their own [1, 4, 5, 8, 9]. In the meantime, they can easily spread the infection through their fecal matter or, less often, saliva [1, 2, 4-6]. Cats usually become infected by getting the virus in their mouths [1, 5, 6]. Shared litter boxes are a typical culprit [1, 2, 4-6]. An uninfected cat needs only to step in the litterbox after an infected cat has used it, and then when they clean their paws later, they become infected themself.

But what does this benign virus have to do with FIP? It isn’t well understood, but in about 10% of cats a FeCV infection turns into FIP [1, 2]. This is believed to occur as a combination of two phenomena. First, FeCV undergoes a spontaneous mutation that enables it to infect macrophages, a type of white blood cell [1, 2, 5, 8, 9]. This is the feline infectious peritonitis virus (FIPV). Second, the immune systems of certain cats overreact to the mutated virus, causing out-of-control inflammation and damage [1, 4, 6]. Incidentally, it is an overblown immune reaction to the coronavirus of the moment, COVID-19, that makes it so dangerous for a proportion of the population.

In the bodies of cats where both of these things happen, FIP develops. Some cats are more prone to FIP than others. Although the specific genetic risk factors remain unclear, specific breeds are at greater risk: Abyssinians, Bengals, Birmans, Himalayans, Ragdolls, Cornish Rexes, and Devon Rexes [6, 8]. Younger cats and most especially kittens make up the majority of FIP cases [1, 4, 6]. Their weaker immune systems are less able to fight off a FeCV infection, giving it more time to mutate [5]. Unneutered cats also seem to be at greater risk, for unknown reasons [8].

FIP symptoms chart
Symptoms of FIP – Image from Cornell University eCommons

Symptoms and Subtypes

The most common and earliest symptoms of FIP are, frustratingly, not very specific. They may include fever, change in appetite, weight loss, and depression [1, 5, 6]. As FIP advances, it develops into one of two general forms: wet/effusive or dry/non-effusive. In the wet form, fluid builds up in the abdominal and chest cavities and may cause breathing difficulty [1, 4-6, 8]. The dry form causes neurological and eye symptoms such as seizures and uveitis (inflammation of the outer layers of the eye) in addition to the non-specific symptoms [1, 4-6, 8].

FIP diagnosis chart
Diagnostic Map for FIP (Hartmann, 2005)

Diagnosis

Diagnosing FIP is difficult and complicated. The symptoms can all be signs of other diseases. Once it is suspected, there is no definitive, foolproof test for FIP. At right is a diagnostic scheme for FIP from one scientific article as an example of the mental gymnastics veterinarians have to do when deciding how to pursue FIP testing.

The options include blood and fluid tests, genetic tests for FIPV, and the veterinarian’s observations during an exam [1, 2, 4-6]. Many of the tests are complicated by the fact that so many cats have been infected by FeCV [1, 2, 5]. A cat’s veterinarian has to determine the best course of testing based on their individual case.

Treatment

Until just a couple years ago, nothing could be done for cats with FIP except supportive care to ease their suffering and extend their life a short time. For many cats, that is still the case, for reasons I will get to shortly, or simply because their disease is too severe. Supportive care consists of subcutaneous or intravenous fluids, draining fluid from body cavities if applicable, steroids to control inflammation, and immunosuppressive medication [1, 2, 4-6].

GS-441524

GS-441524 is an antiviral drug that prevents viruses from synthesizing RNA, a molecule which many viruses, including FeCV/FIPV, use instead of DNA [3, 9]. It was created by the pharmaceutical company Gilead, which specializes in antivirals [9]. Gilead first tested GS-441524 against Ebola but was ineffective [9]. However, FIP researcher Niels Pedersen knew someone at Gilead and asked if they could send him anything to test [9]. His friend at Gilead obliged, and Pedersen found two promising candidates that killed FIP in cultured cat cells [9]. He moved on with testing one of them, GS-441524, in cats with FIP [9].

The results were incredible. In a laboratory study, ten of ten infected cats recovered [9]. In a field trial with 31 pet cats with non-neurological FIP, 25 recovered, still an unheard-of success rate for this otherwise inevitably fatal disease [7, 9]. A more recent pilot study suggests that GS-441524 is effective in neurological and ocular FIP, too [2]. Side effects were not too bad. Cats experienced pain and skin reactions at the injection site, sometimes developing sores or scars [7]. This may be because the formula is very acidic [7].

Gilead, however, has declined to license GS-441524 for animal use [9]. GS-441524 is almost identical, molecularly, to another one of their drugs, remdesivir, which they are trying to get licensed for human use, and they believe that licensing GS-441524 for FIP would harm their chances with remdesivir [9]. Cat people and Chinese entrepreneurs have gotten creative, however.

GS-441524 is not a difficult molecule to synthesize, so numerous outfits in China have chosen to manufacture and sell it, filling the gap Gilead left open [9]. Because GS-441524 is not FDA-approved, veterinarians cannot prescribe it, and it’s illegal for cat parents to purchase and administer it [1, 9]. That has not stopped desperate people who want to save their cats. Because it is a black market, there is a risk that the product will not be as advertised [1, 9]. And it is incredibly expensive: it costs 7,000-12,000 USD for the 12-week course of medication [9]. When people can manage to acquire it, however, GS-441524 seems to be as good as the research suggested [1, 9].

If your cat has been diagnosed with FIP, and you would like help accessing GS-441524 treatment, contact FIP Warriors.

Watch “Kitten Lady” Hannah Shaw’s journey through FIP with her cat Coco

Preventing FIP

Because FeCV is so common and easily spread, it’s hard to prevent FIP entirely. There are some things you can do, however. Keep litter boxes clean and far away from food and water dishes [1, 6]. Cats are more vulnerable to developing FIP if they have another disease like FeLV or FIV, so get your cats vaccinated against all those easily preventable diseases [1, 6]. There is one FDA-approved vaccine against FeCV, but it does not seem to be all that effective [1, 5, 6]. You can always ask your veterinarian about the FeCV/FIP vaccine if you’re concerned, however. Keep in mind that cats often get FeCV infections at animal shelters and catteries, so you may want to isolate any new cats for a couple weeks [1, 5].

Works Cited

  1. Cornell Feline Health Center. (2020). Feline infectious peritonitis. Cornell University College of Veterinary Medicine. Link
  2. Diaz, J. V. & Poma, R. (2009). Diagnosis and clinical signs of feline infectious peritonitis in the central nervous system. The Canadian Veterinary Journal, 50(1), 1091-1093. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2748294/
  3. Dickinson, P. J., Bannasch, M., Thomasy, S. M., Murthy, V. D., et al. (2020). Antiviral treatment using the adenosine nucleoside analogue GS-441524 in cats with clinically diagnosed neurological feline infectious peritonitis. Journal of Veterinary Internal Medicine, 34(4), 1587-1593. https://doi.org/10.1111/jvim.15780
  4. Feline infectious peritonitis (FIP). (n.d.). Veterinary Specialty Center. https://www.vetspecialty.com/feline-infectious-peritonitis-fip/
  5. Hartmann, K. (2005). Feline infectious peritonitis. Veterinary Clinics: Small Animals Practice, 35(1), 39-79. https://doi.org/10.1016/j.cvsm.2004.10.011
  6. Levy, J. K. & Hutsell, S. (2020, October). Feline infectious peritonitis (FIP). Merck Veterinary Manual. https://www.merckvetmanual.com/cat-owners/disorders-affecting-multiple-body-systems-of-cats/feline-infectious-peritonitis-fip
  7. Pedersen, N. C., Perron, M., Bannasch, M., Montgomery, E., et al. (2019). Efficacy and safety of the nucleoside analog GS-441524 for treatment of cats with naturally occurring feline infectious peritonitis. Journal of Feline Medicine and Surgery, 21(4), 271-281. https://doi.org/10.1177/1098612X19825701
  8. Pesteanu-Somogyi, L. D., Radzai, C., & Pressler, B. M. (2006). Prevalence of feline infectious peritonitis in specific cat breeds. Journal of Feline Medicine and Surgery, 8(1), 1-5. https://doi.org/10.1016/j.jfms.2005.04.003
  9. Zhang, S. (2020, May 8). A much-hyped COVID-19 drug Is almost identical to a black-market cat cure. The Atlantic. https://www.theatlantic.com/science/archive/2020/05/remdesivir-cats/611341/

Published June 15, 2022

Updated November 12, 2023

Cat Care

Should You Give Kittens as Christmas Gifts?

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Do you remember FurReal toys? They probably still exist, but I remember one year when I was little, the FurReal Friends cat was a hot toy for Christmas. And I wanted it. Bless her, my mom managed to get one. I woke up Christmas morning to an orange-and-white robo-kitty. It was pretty cool. Electronic toys were a little bit of a novelty even then. And it was like having a cuddly kitty, too! Well, in a janky robot sort of way. But as is sometimes the case with children and their toys, I got bored of it after a while. I’ve never wanted to give pets as gifts, for any holiday or occasion, for that very reason. But animatronic toys aren’t real pets, and I’m no expert. So what do the actual authorities think about gifting pets?

I found it! It’s so much creepier than I remember…

Reasons to Gift

Anyone who has been lucky enough to have a pet in their life understands the joy that pets bring. It goes without saying why we might want to give that joy to someone we love. That’s not to mention all the homeless pets out there who deserve a family. But I had heard my whole life it’s a bad idea to give pets as gifts. I was surprised to learn how much support there is in the animal welfare and rescue community for the practice.

Starting in the 1990s, several research groups studied the reasons that people surrender animals to shelters (1, 2, 3). The American Society for the Prevention of Cruelty to Animals (ASPCA) followed up with a study that specifically considered pets given as gifts (3). In 1999, Scarlett et al. surveyed pet owners who surrendered their cats and dogs to county animals shelters with a focus on any “health and personal issues” that influenced them to do so (1). Of the ten major reasons given, the pet being an unwanted gift came dead last for both cats and dogs (1). The #1 reason? For cats, it was allergies, and for dogs, it was not having enough time (1).

New, Jr. et al. compared surrendered pets and their former owners to homed pets and their owners (2). They considered the source of the pets as a possible factor, and in some cases there was a significant difference. For example, cats and dogs purchased from pet shops were more likely to be given up (2). But the proportion of pets that had been gifts was the same in shelters as in homes (2). In other words, it made no difference in the rate of surrender that an animal had been a gift.

Most recently, the ASPCA decided to take a hard look at what happens when we give pets as gifts. In their 2013 study, they created a telephone survey to find and interview people who had been given a pet in the past ten years (3). The three survey questions of interest were:

  1. Were you involved, in any manner, in the selection process of the pet that you received as a gift?
  2. Did receiving a pet as a gift increase, decrease, or have no impact on your love or attachment to the pet?
  3. Is that pet still with you?
Tabby kitten with red gift ribbon on head
Photo by Avel Chuklanov on Unsplash

Most people said that they were either involved in picking out their gifted pet, or they were were surprised and okay with that (3). 97.2% reported that receiving their pet as a gift either didn’t change how much love/attachment they felt or actually increased it (3). Only seven of the 222 pet owners surveyed said that they felt less attached because their pet was a gift (3). Only 9.8% said that the pet was now in a new home (3). In the vast majority of cases, respondents still had the pet, but about as many had since died as been rehomed (3).

To summarize all those numbers, the data suggest that most of the time, the gift of a pet is appreciated. So these days, more animal welfare groups and rescue organizations support giving pets as gifts. After all, one of their primary goals is to get as many pets as possible into forever homes. As long as those gifted animals aren’t being returned to sender, at least no more than any others, then it’s just another way to get pets out of shelters and into loving homes.

Reasons Not to Gift

Contradicting all of that painstaking research are the statements of shelter staff and volunteers who say that surrenders see a surge around the holidays. Audra Stillabower, a Veterinary Information Specialist at the Pet Poison Helpline who worked in shelters for eight years, reports a spike in surrenders both before and after the holiday season (4). Before, because people are surrendering older pets to make way for new ones, and after because people realize they don’t want that live holiday present after all (4). Executive Director Cheryl Miller of the Wichita County, Texas Humane Society echoes that sad sentiment (5).

“I would bet we get at least ten calls a week with people having animals that ‘we just don’t have time,’ ‘this was given to us as a gift,'” says Anne Halbert of January at her Nebraska shelter, Start Over Rover (6). How can this be the case when there is so much data to support the position that people don’t usually abandon gifted pets? I couldn’t find an answer. I wonder if location makes a difference. Gina Knepp, a spokesperson for Front Street Animal Shelter in Sacramento, California, said “We don’t see a higher rate of abandonments during this time of year as compared to other times of the year” (7).

I don’t know about Wichita County, but I know that Nebraska tends to get a lot of wintry weather, and Sacramento very much does not. I could see why the best time to get a new puppy that needs to go outside, like, every twenty minutes wouldn’t be when there’s two feet of snow on the ground. It’s just a theory, though, and the weather probably wouldn’t have as much of an impact on whether someone kept a new cat or not. Whatever the reason for the discrepancy, we know that some gifted pets are “returned.” If you choose to give a pet as a gift, it’s your responsibility to think some things through first. And if you are not absolutely certain that the person is interested in a pet, do not give them a pet (4, 7-10).

Pomeranian dog in red gift box
Photo by Jill Wellington from Pexels

The Best Way to Give a Gift that Keeps on Purring

It is very important for a new pet to fit well with their new owner and that person’s life. There are a couple ways that you, as the one intending to give the pet, can ensure that your gift is a good one. One is to take the recipient with you and pick out the pet together (4, 8, 10). Another is to buy an adoption certificate instead of a pet and give that as the gift (7, 8, 9). Adoption certificates are offered at many shelters and allow you to pay the adoption fees without taking home a pet. Then, the recipient can go pick out whatever pet they want. Or, if they decide they don’t want a pet, the gift ends up being a donation to the shelter in the honor. That’s not a bad deal either.

In terms of presentation, a cute suggestion is tying a note or adoption certificate to a plush/toy pet (9). After all, live animals don’t really belong in wrapped boxes, under Christmas trees, etc. The only pet I can think of that is appropriate to actually package up would be sea monkeys. Maybe an ant farm? But that’s it. No matter what the movies sometimes tell us.

Because pets are expensive, it would be courteous to provide some extras with the pet, especially if you know the recipient doesn’t have all the equipment already. Maybe wrap up a pet starter kit to give them the day of the holiday or special occasion (7, 8).

If you decide to give pets as gifts this holiday season or any time in the future, do so wisely but also in the knowledge that the data says it is a good way to give animals loving homes. And remember, adopt, don’t shop! Choose to give pets from shelters and rescues. Even purebred cats and dogs and unusual pet species can be found in these places. Don’t purchase a pet from a breeder when there are homeless ones waiting for that special someone already. I don’t know about you, but saving an animal’s life sounds like an amazing gift to me.

Works Cited

  1. Scarlett, J.M., Salman, M.D., New Jr., J.D., Kass, P.H. (1999). Reasons for relinquishment of companion animals in U.S. animal shelters: Selected health and personal issues. Journal of Applied Animal Welfare Science, 2(1), 41-57. doi: 10.1207/s15327604jaws0201_4
  2. New Jr., J.D., Salman, M.D., King, M., Scarlett, J.M., et al. (2000). Characteristics of shelter-relinquished animals and their owners compared with animals and their owners in U.S. pet-owning households. Journal of Applied Animal Welfare Science, 3(3), 179-201. doi: 10.1207/S15327604JAWS0303_1
  3. Weiss, E., Dolan, E.D., Garrison, L., Hong, J., et al. (2013). Should dogs and cats be given as gifts? Animals, 3, 995-1001. doi: 10.3390/ani3040995
  4. Stillabower, A. (n.d.). Giving animals as Christmas gifts. Pet Poison Helpline. https://www.petpoisonhelpline.com/blog/giving-animals-christmas-gifts/
  5. Connor, C. (2019, December 3). Plan ahead before giving pets as a Christmas gift. News Channel 6 Now. https://www.newschannel6now.com/2019/12/04/plan-ahead-before-giving-pets-christmas-gift/
  6. Dickeson, K. (2019, December 4). Animal shelters advise against giving pets as holiday gifts. KSNB Local 4 Hastings. https://www.ksnblocal4.com/content/news/Animal-shelters-advise-against-giving-pets-as-holiday-gifts-565809791.html
  7. Escalante, E. (2018, December 18). Pets as Christmas gifts: Why shelters say it’s okay to give a pet as a gift. ABC 10. link here
  8. Picard, C. (2019, July 24). Why pets can make good gifts, according to animal adoption experts. Good Housekeeping. Retrieved from https://www.goodhousekeeping.com/life/pets/a28410545/why-pets-make-good-gifts/
  9. Mettler, L. (n.d.). Pets as presents: A good idea? Petfinder.com. https://www.petfinder.com/pet-adoption/dog-adoption/pets-as-presents/
  10. Oregon Veterinary Medical Association. (2017, December 18). Giving pets as gifts: Consider the choice carefully. https://oregonvma.org/care-health/basics/giving-pets-gifts

Published December 7th, 2020

Updated May 12th, 2023