Feline Infectious Peritonitis (FIP) is a serious and often fatal disease affecting cats, caused by a mutation of the feline coronavirus. Understanding FIP is essential for cat owners, especially those with multiple cats, to prevent spread and ensure early intervention. Households with several cats are at greater risk as the virus can be transmitted through faeces and respiratory secretions, contaminating shared spaces. People can also inadvertently carry the virus on their hands or clothing between cats, so good hygiene helps reduce transmission risk.
The virus primarily targets cats with compromised immune systems, including young kittens with immature immunity, and older cats whose immunity may decline with age. It spreads within the cat's body via infected white blood cells. While kittens from 3 months to 3 years are most vulnerable, senior cats may also develop FIP due to weakened defences. The disease is caused by a mutation of the common feline coronavirus found in many healthy cats, which mutates in some individuals leading to FIP.
FIP manifests in two main forms with differing symptoms:
Both forms cause general signs such as dull coat, weight loss, lethargy, and depression. The wet form tends to progress rapidly with symptoms including persistent fever not responding to treatment, loss of appetite, swollen abdomen, breathing difficulties, sneezing, and nasal discharge. The dry form can lead to slow poor growth in kittens, anaemia, jaundice, fever, eye inflammation, and neurological signs like vision loss or lack of coordination.
FIP occurs when a typically harmless feline coronavirus mutates within the cat’s body, especially if the immune system struggles to control it. This mutation converts a standard coronavirus infection into the much more severe FIP virus which invades and infects white blood cells. The virus may lie dormant for months before mutation and disease onset. This complex interaction explains why not all cats exposed to the coronavirus develop FIP.
Diagnosing FIP can be challenging due to overlapping symptoms with other diseases. Veterinary diagnosis often involves a combination of tests including:
In complicated cases, exploratory surgery may be necessary to obtain tissue samples for definitive diagnosis.
Treating FIP remains difficult but recent advances have transformed outlooks for some cats.
Early veterinary intervention and close monitoring by your vet are essential to optimise treatment success and maintain your cat’s quality of life.
The prognosis for cats diagnosed with FIP is often guarded, especially with the wet form. Providing supportive care at home focused on comfort is key. During active disease stages, affected cats should be separated from others to reduce coronavirus spread. Cleaning and disinfecting living areas and feeding bowls regularly is crucial in multi-cat households.
While FIP remains a daunting diagnosis, ongoing research and treatments such as antiviral therapy offer new hope for many cats and their owners.
For advice on finding healthy cats or kittens, choosing responsible breeders, or adoption, always consult qualified professionals.