Feline Infectious Peritonitis and Coronavirus Web Site

Feline Infectious Peritonitis (FIP) is an unusual, but often fatal, consequence of coronavirus infection of the cat. The majority of cats (and ferrets) infected with coronaviruses seem to lead perfectly normal lives. However, if you are thinking of buying a pedigree (purebred) kitten - INSIST that he or she is feline coronavirus (FCoV) free - otherwise you may be buying heartache.

1. Good news: Bova Compounding now has an oral formulation of GS-441524 which will make dosing easier and safer than pilling. Read more about FIP treatment here: https://www.catvirus.com/treatment.htm

2. Not so good news: GS-441524 adverse effect. The Minnesota Urolith Center has discovered bladder stones formed from GS-441524: this side effect is another reason for using this antiviral drug for as short a duration as required to cure FIP. Cure (as opposed to remission) from FIP can be ascertained by two consecutive normal AGP tests a week apart. SAA level return to within normal levels may also be predictive of full FIP recovery, but has not yet been published.

In the news section below you'll see the announcement of kittens born in the households of two UK FCoV-free cat breeders: provided these kittens don't become infected with feline coronavirus in their new homes, they will not develop FIP. Preventing FCoV infection (or early treatment of feline coronavirus) prevents FIP: we have now proven that scientifically (Addie et al, 2023). A paper published in Feb 2012, showed how quarantine and FCoV antibody testing has kept the Falkland (Malvinas) Islands free of FCoV and FIP.

1. To provide accurate and up to date information about feline coronavirus (FCoV), the cause of feline infectious peritonitis (FIP) in cats.

2. To provide a register of FCoV tested studs and queens so that enlightened cat breeders who know their cat’s FCoV status can contact each other. In the 1970s, Abysinnian cat breeders began testing for FeLV and eliminated it from their breed, other cat clubs followed suite. Now, at least in the UK, it is extremely rare for a pedigree kitten to be sold with FeLV, thanks to the dedicated testing of cat breeders. In Scotland, most Birman breeders are FCoV free. The war against coronavirus and FIP has begun - I hope you will join it.

8. To provide lists of genetic/hereditary diseases and disease predispositions of breeds of cats

Breaking news - our paper on early treatment of feline coronavirus using oral (NOT injectable) antiviral drugs prevented FIP has been published and can be found here: https://www.mdpi.com/1999-4915/15/4/818. This has now been done successfully by dozens of people and there has been no sign of antiviral drug resistant virus mutants appearing, which is the major concern. Such mutant coronaviruses are most likely to appear when injectable antivirals are used for FIP treatment because we know that injected GS-441524 does not adequately reach the intestine, which is the major site of feline coronavirus replication. One FIP cat successfully treated with GS-441524 injections still shed virus in his faeces at least two years post-treatment (Addie et al, 2022).

Sadly, our attempts to stop FCoV shedding using itraconazole (Itrafungol) were unsuccessful: it reduced, but did not eliminate, the virus from faeces and virus load bounced back as soon as the itraconazole was stopped. We continue to search for alternative therapies so that using GS-441524 can be avoided and that drug be saved for treating FIP.

Our paper on differentiating cats who are cured of FIP from cats in remission has been published and can be found here: https://www.mdpi.com/1999-4915/14/4/744/htm#. This paper tells you how to know when it is safe to discontinue FIP treatment. One of the biggest fears amongst people treating cats for FIP is that the cats may relapse: to avoid a relapse, please download our 10 Rules for Preventing FIP relapses.

Together with Dr Mark Fosbery, Mrs Johanna Covell-Ritchie, and Prof. Oswald Jarrett, I published a case report on the use of GS-441524 (Mutian X) pills and Virbagen Omega feline interferon to cure a cat who had non-effusive FIP. An excellent study from Prof. Hartmann's group in Germany showed that Mutian X pills are safe and effective, and that they contain GS-441524 (the study can be read here: www.mdpi.com/1999-4915/13/11/2228). In the UK and Australia, GS-441524 pills (and now a liquid) can legally be purchased by veterinary surgeons from Bova Specials Ltd.

Thanks to the generosity of the Catvirus.com subscribers and donors who helped fund the publication fee, this paper is free for all to read and download:

FCoV free pedigree kittens: British Ragdoll breeder, Baker Street Ragdolls produced her first litter of kittens since going FCoV-free in 2019:

In 2020 we published a paper showing that Mutian X pills can stop FCoV shedding: this is what this breeder used to rid her household of feline coronavirus, the virus that causes FIP: she has now produced over 100 kittens - all FCoV free! The paper is called " Oral Mutian®X stopped faecal feline coronavirus shedding by naturally infected cats " and was published in the journal Research in Veterinary Science. I want to thank all the crowd funding donors who paid for the paper to be open access and huge thanks to Kristina Macaulay for organising that appeal. I also sincerely thank one of the reviewers who really helped to iron out flaws in our original draft: scientific review is anonymous and unpaid, and this person gave of her (or his) time to hugely improve the paper.

And as always - MANY THANKS to all those subscribers who support me, and to the Angelica Fund donors who paid for this research - all of you made that study possible! We are also grateful to Dr Xue of Mutian for donating pills for two of the households who took part in the study.

There are now at least five cat breeders who have eradicated FCoV from their beautiful cats. In the 1970s it was the cat breeders in the UK who led the way to almost eradicating feline leukaemia virus (FeLV) from the UK: that virus is now rare in the UK and the Netherlands. Around 70% of FIP occurs in pedigree / purebred kittens, if cat breeders become FCoV-free, that will prevent the majority of FIP from occurring.

My research on the effect of cat litter on FCoV transmission has been published in JFMS. Dr Elsey's Cat Attract was found to reduce FCoV transmission in two households of cats who had endemic FCoV infection. Become a catvirus.com subscriber to obtain the latest newsletter with details on this important research.

Non-effusive FIP diagnosis just got easier - our paper Diagnosis of non-effusive feline infectious peritonitis by reverse transcriptase quantitative polymerase chain reaction from mesenteric lymph node fine needle aspirates was published online: https://journals.sagepub.com/doi/full/10.1177/1098612X18809165. We are hoping that our new test will save cats from being put through invasive biopsies in order to achieve a diagnosis of dry FIP. Read more about it in my most recent newsletter.

Feline coronavirus transmission video has now had over 250,000 views on YouTube and my subscriber number finally topped the 1000 mark! So a big thank you to everybody who has given it the thumbs up and subscribed to my YouTube channel. Huge thanks also to the catvirus subscribers who enable more educational videos to be made.

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Mission statement: I want to eradicate feline coronavirus (FCoV) and feline infectious peritonitis (FIP). The purpose of this website is to make FCoV/FIP information available to the veterinary profession and to help and guide distressed cat guardians when they receive a diagnosis of FIP.

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This book is available as an e-book from this website - see above - or as a paperback or kindle in English or Spanish from Amazon:

Download a free sample eBook of "My Cat Has FI P - What Now?"

This book is written for anybody unfortunate enough to have had FIP diagnosed in their cat. It will help you through the maze that is FIP diagnosis, to decide what your options are for treatment and to safeguard your other cats, or how and when to safely add a new cat to your household.

Please note that this is a zip folder containing an .exe file and that you may have to alter your firewall or virus protection program to allow it to download. This is a new experiment for us, so please let us know if you encounter any problems downloading it (email e-books [at] catvirus.com). You can still use the regular Buy Now buttons below to purchase the e-book if you prefer.

At present, you can only buy the whole eBook directly (and within minutes) from the sample eBook in US dollars. To buy it in GB pounds or Euros, please use the Paypal links below and we will manually send you an activation key within 24 hours. A physical version can be obtained from any of the Amazon websites.

Note that everything in these books is available for free here on the website!

...... Download a current FIP treatment sheet from the Downloads menu to take with you to your veterinary surgeon.

5. Everything you need to know if your cat or kitten is diagnosed as having diarrhoea caused by FCoV

6. Everything you need to know if you work in a rescue shelter or boarding cattery

8. Everything you need to know if you keep a lot (over 6) pet cats, or have a cat sanctuary or colony

As regular visitors to the site will know, one of my dreams is to eradicate FCoV, and therefore FIP, from the whole world! Some years ago, the veterinary surgeons on the Falklands Islands, suspecting that the cats who lived there were already FCoV free, instituted a policy where all cats being imported to the Islands had to test negative for antibodies to Feline Coronavirus, the virus which cases Feline Infectious Peritonitis (FIP). We published a paper (will open in a new window) in the Journal of Feline Medicine and Surgery (JFMS), the journal of the International Society of Feline Medicine, showing that this policy was effective.

On a smaller scale, you can keep the cats in your household FCoV free (and therefore FIP free) by testing new incoming cats and kittens for FCoV antibodies BEFORE bringing them into the house. Too often I hear sad tales of an existing pet developing FIP after the introduction of a cat or kitten from a high-risk source, such as a breeder or rescue shelter. There are good breeders out there producing FCoV-free kittens - be sure to demand a FCoV antibody test before purchase. If the test turns out to be positive, then one can test the faeces to determine whether the cat is actually shedding virus, and if so, wait 2-3 months and re-test if you're keen to have that particular cat (or rehome the cat to somebody with no other cats).

CPD for veterinary surgeons: this section is undergoing updating, but news of webinars, new videos and papers get sent to my veterinary subscribers, so please watch your inboxes and if my emails go to spam, please whitelist my address.

When I began this website, FIP was incurable. Now, Professor Niels Pedersen, of the University of California, Davis, has given us an anti-viral which has caused remission in 24 of 31 cats, as reported in his paper published February 2019. The anti-viral, GS-441524, is not yet easily available or affordable. However, pills called Mutian, which also contain a nuceloside analogue, are curing many cats in my experience.

Feline interferon omega (Virbagen Omega by Virbac) has cured some cases and given others a period of remission. For cats with FIP-related lymphopenia, many cats are given Polyprenyl Immunostimulant from Sass & Sass.

My dream is for no cat ever to contract FIP in the first place, never mind die of it.

I am happy to announce that my You Tube channel dealing primarily with Feline Infectious Peritonitis and Feline Chronic Gingivostomatitis, has already been viewed over 200,000 times. However, since YouTube was taken over by Google, it has deteriorated dramatically in quality and it no longer respects free speech, but has become a propaganda machine like the dinosaur media it once replaced. Therefore I now upload my videos first to Bitchute, who seem to respect the values of human freedom. Below are the links to my channels (they will open in new tabs).

Rumble channel: unfortunately in France we cannot access Rumble due to the tyrant Macron, so I cannot continue to upload to Rumble at present.

I am deeply grateful to talented French veterinary animator Dr Francois Bagaini of Vetocyte.fr for bringing some of my ideas to life by his animations. These videos form a key part of my dream to eradicate FCoV and therefore FIP - once people learn how to prevent their cats catching the infection, then FIP will simply no longer occur. Please share the videos and press the thumbs up "like" button if you would like to help eradicate FIP ,

Our most recent video shows how people can prevent FCoV gaining entry into their household of cats by testing newcomer cats (or kittens) for FCoV antibodies:

Here is our cartoon indicating how FCoV is transmitted, this video has already had over 228,000 views of the English version:

It has been known for a while that ferrets had a unique coronavirus of their own (ferret enteric coronavirus, FECV) which causes epizootic catarrhal enteritis [3,4]. They also suffer from a disease which looks very much like infectious peritonitis of cats [1,2] and I am most grateful to Dr Jerry Murray, a ferret expert in Dallas, Texas, for bringing this to my attention.

Reported clinical signs include anorexia, weight loss, diarrhoea, large palpable abdominal masses. Effusions have not been described. Antibody against feline infectious peritonitis virus can be used in immunohistochemistry to confirm diagnosis.

At present moment, treatment is similar to that of FIP in cats - prednisolone. It is unknown whether interferon would help these ferrets or whether Primucell vaccination (Pfizer) would be effective in preventing it, though there is no reason to suppose it would not be protective (however, it would be used off-licence).

Addie DD, Toth S, Herrewegh AAPM, Jarrett O. 1996. Feline coronavirus in the intestinal contents of cats with feline infectious peritonitis. The Veterinary Record. 139: 522-523.

Addie DD, Jarrett JO. 2001. Use of a reverse-transcriptase polymerase chain reaction for monitoring feline coronavirus shedding by healthy cats. Vet. Rec. 148:649-653.

Addie D.D, Schaap I.A.T, Nicolson L, Jarrett O. 2003. Persistence and transmission of natural type I feline coronavirus infection. J. Gen. Virol. 84 (10): 2735-2744.

Addie D, Houe L, Maitland K, Passantino G, Decaro N. 2020. Effect of cat litters on feline coronavirus infection of cell culture and cats. J Feline Med Surg. 22(4) 350–357. doi.org/10.1177/1098612X19848167.

Addie, D.D.; Silveira, C.; Aston, C.; Brauckmann, P.; Covell-Ritchie, J.; Felstead, C.; Fosbery, M.; Gibbins, C.; Macaulay, K.; McMurrough, J.; Pattison, E.; Robertson, E. Alpha-1 Acid Glycoprotein Reduction Differentiated Recovery from Remission in a Small Cohort of Cats Treated for Feline Infectious Peritonitis. Viruses 2022, 14, 744. https://doi.org/10.3390/v14040744

Juan-Salles C, Teifke JP, Morera N, Jiminez J, Montesinos A, Ardiaca M, Loehr CV, Garner MM. 2006 Pathology and immunohistochemistry of a disease resembling feline infectious peritonitis in ferrets (Mustela Putorius Furo). Vet Pathol 43:5 p845

Williams BH, Kiupel M, West KH, Raymond JT, Grant CK, Glickman LT. 2000 Coronavirus-associated epizootic catarrhal enteritis in ferrets. J Am Vet Med Assoc 217(4):526-30.

Wise AG, Kiupel M, Maes RK. 2006 Molecular characterization of a novel coronavirus associated with epizootic catarrhal enteritis (ECE) in ferrets. Virology. 349(1):164-74.

Italian cat breeders and veterinary surgeons filled the hall to hear about FIP and Coronavirus in Tuscany in June 2013

The event was organised by the wonderful Loretta Bartolucci and Italian veterinary surgeon Dr Francesca Serena, who gave an introductory lecture on stress and feline welfare. Francesca and Loretta can be seen below flanking the translator Nico, who did a really excellent job.

I was proud to be invited to contribute to the Fourth Edition of Prof. Craig Greene's legendary textbook "Infectious Diseases of the Dog and Cat." For me, this is the Bible of canine and feline infectious disease. It is available from Amazon. [Note - it is for veterinary surgeons only.]

Dr Diane D Addie is a veterinay surgeon and virologist who has spent the last 23 years researching feline infectious peritonitis (FIP) and feline coronavirus infection (FCoV). She qualified as a veterinary surgeon from the University of Glasgow, in Scotland, and spent 8 years in small animal practice in the north of England. She returned to Glasgow Veterinary School to research into FIP, her PhD was entitled "Studies on the humoral immune response to feline coronavirus." She is Honorary Senior Research Fellow at the University of Glasgow, Scotland, U.K and Director of the Feline Institute Pyrenees in France. Dr Addie serves on the European Advisory Board of Cat Disease.

Her dream is to eradicate FIP, at least from pedigree/purebred cats, and preferably also from rescue shelters, within the next 10 years. By becoming informed and spreading reliable knowledge, or by fundraising for research you can help her fight FIP.

She takes the stand that she prefers not to experiment on animals and all her studies have been on animals who have become infected or sick naturally and whose veterinary surgeons or guardians have contacted her.

In 2003 she received the Amoroso award for for outstanding contributions to small animal studies by a non-clinical member of university staff. She served on the council of Cats Protection for 20 years and is currently a patron of the Celia Hammond Animal Trust.

The opinions and recommendations given on this website are completely independent - Dr Addie is not in on the payroll of any corporation, nor does she hold shares in any company mentioned on this site, nor is she on any board of directors of any corporation or company whose products are mentioned on this site, with the exception of the ebooks for sale on this site, where she receives up to 65% of the income, this being her main source of income. Dr Addie takes no income from donations made to the Angelica Trust.

She is a member of the European Advisory Board of Cat Disease whose meetings are funded by Merial, but whose veterinary members are volunteer and are unpaid. Merial simply pays the travel expenses and hotel.

Your use of this website at your own risk. This site is for information purposes only and is in no way intended to replace a consultation with a fully qualified veterinary surgeon (veterinarian). The information in this site cannot and should not be used as a basis for diagnosis or choice of treatment. Dr Addie excludes all liability whatsoever for any loss or damage arising out of use of this site or reliance upon its contents and strongly advises all users with veterinary related queries to consult a veterinary surgeon.

The answer to most of your FIP questions is here on the website and in my book "FIP and Coronavirus." If you do want a consultation with me, details of how to do so are below: please note thatI will HAVE to have your veterinary surgeon's consent before I can give you my opinion (RCVS rules).

Emails to my former address (draddie[at]btinternet.com) will no longer be received / replied to. Emails to my University of Glasgow email address will still be received, but there is a very long delay in getting them, thus a delay in responding.

For private, individual, consultation regarding your own pet, you must obtain the permission of your veterinary surgeon in writing for me to consult with you before you contact me (these are the rules of the Royal College of Veterinary Surgeons). Email: draddie [at] catvirus [dot] com.

* Because of the high input of my personal attention and time to the people in this group, this option is limited to only 10 people at any one time, so may not be available, but you can try it and see: if there is no vacancy you can take a one month option or get a refund.

Dr Diane D. Addie is available for consultations for infectious disease control or diagnosis to veterinary hospitals, rescue shelters, boarding and breeding catteries and industry. She is also available to laboratories for consultation for the development of diagnostic tests.

Melody Amundson made this site possible by generously offering her fantastic web designing skills free of charge as her generous donation to the cause of fighting Feline Infectious Peritonitis. She gave of her time and skills for over 8 years to keep this website working! You can see how artistic she is from the beauty of this website and the Orion Foundation website, and another example is her lovely colouring book for children, which you can purchase from her Devon Heaven website. Melody is a breeder of Devon Rex kittens and is active in the cat show world in the USA. She also forays into the world of cat rescue and any cat who crosses her path will benefit from the encounter!

Renata Fernandes of rftranslations arranged translations of the site into other languages. Each language had 4 translators working on the website's text plus a proofreader at the end. Over 30 people from different parts of the world were willing to help get rid of coronavirus by using their translating skills and did so ENTIRELY VOLUNTARILY! This was an astonishing donation to help spread the word on FIP!

Unfortunately I am unable to answer all the queries that come to my inbox. I'm very sorry, but I'm sure you'll appreciate that every moment spent responding to queries is a moment less to devote to research. In addition, it would be unethical for me to advise another veterinary surgeon's client without their consent. Time permitting, if you donate to FIP research and provide written consent for me to respond to you from your veterinary surgeon, I will try to answer some queries. Go to the Angelica Memorial Page to make a donation.

Forums and chat groups provide support and answer queries for people with a cat suspected of having FIP or for those who are unfortunate enough to have lost a cat to FIP. The one I personally recommend is the FIP Advisory and Care group:

I also host a subscription only Facebook page called EndFIP which can be found on this address:

The site is continually being updated and new material added. I hope that you will find the answer to your questions here and that you’ll come back soon.

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