Breeders, Shelters & Rescues

This title is purposeful as FIP is like that deviant stalker, ever watchful, ever ready to pounce and cause havoc. And while FIP remains one of the most misunderstood diseases of today, there is no getting away with the fact that it is also one of the most feared diseases in rescues and catteries worldwide. And with good reason! FIP kills. For long there has been a severe chasm that divides breeders and rescuers. Often a divide that can come to blows yet FIP is the one thing that doesn’t discriminate between either. IT is a common ground that exists between these two opposite camps – to understand this disease and how to control it.

So, as always, before you can do anything you need to know what you are dealing with. FIP stems from a mutation of the feline coronavirus. This virus differs from other feline viruses in a number of ways, namely:

1. Antibodies may play a role in the development of FIP itself and may not serve a protective function

2. Antibody titres are not a useful diagnostic toll for FIP or its prognosis, and

3. A vaccine is available but this itself causes much heated debate.

The first confusion arises with the nomenclature of this disease and some tests associated with it. The various terms are FCoV, FECV, FIPV, FIP …all related but very dissimilar. FCoV denotes what is generally called Feline Coronavirus. FCoV can be likened to twins (courtesy Dr Susan Little DVM, DABVP (Feline)), one good, known as FECV, and one evil, known as FIPV. Together FECV and FIPV make up FCoV. The good twin is the more common and benign form of the virus and is referred to as FECV or feline enteric coronavirus while the bad twin, the pathogenic form, is referred to as FIPV (feline infectious peritonitis virus). What is important to note is that feline coronaviruses are complex and due to their RNA structure they are not set in stone as two definitive strains and most field strains are intermediate between the two extremes. The twins are not genetically distinguishable and no test exists to isolate one from the other. It is the pathogenic form of the virus that has the capacity to mutate to the nasty disease we all have come to dread, FIP or feline infectious peritonitis.

Both catteries and rescue shelters are at risk because of the number of cats housed and the use of common toilet facilities. FIPV and FECV can be found within these colonies and it is possible for a small percentage of our good twin, FECV, to defect to the dark side and mutate to FIPV. But it is FIPV that is the coronavirus that mutates to form FIP. Colonies are the ideal places for this mutation to occur because most, if not all, conditions are met. Mutation occurs when any of the four factors come to together to create a perfect storm – a genetic susceptibility, exposure to and infection with FCoV (due to chronic shedders and cat-dense environments), immunity issues and a stressor. The mutation occurs within individual cats and it is accepted knowledge that cats cannot ‘catch’ FIP; they develop it within their selves from their own mutant strain of the virus. How the cat responds is responsible for the clinical signs we see and why there is such a spectrum of what we see. The mechanism of infection is widely documented and available for anyone, but the best source is the YouTube video by Dr Diane Addie PhD, BVMS, MRCVS https://youtu.be/rkqUjeQNEQs

Controlling feline coronaviruses is paramount if any rescue shelter or cattery is to be successful. The methods will differ because the management is different. It is therefore best to discuss them as two separate entities.