Feline infectious peritonitis

What is feline infectious peritonitis?

FIP is a fatal disease affecting cats and kittens. Caused by a common virus called feline coronavirus, there are two forms: wet (effusive) and dry (non-effusive). Both are serious and can be fatal, but cats with the effusive form have a shorter life expectancy. The virus spreads through the whole body, and symptoms will vary from cat to cat.

What is feline coronavirus?

Feline coronavirus is a virus that infects cats through contact with infected feces.

This can occur when they groom each other, or when they share litter boxes, food bowls or grooming equipment.

How does feline coronavirus cause feline infectious peritonitis?

There are two main types of feline coronavirus that affect cats and kittens:

• Enteric coronavirus
• The coronavirus that causes FIP

The so-called "enteric" coronavirus is mainly restricted to the intestines. It multiplies there and may cause diarrhea—this is particularly likely to happen to kittens, especially when they live in communities with other cats. Very often, the virus has no symptoms.

The coronavirus that causes FIP, is currently considered to be a mutant form of the enteric coronavirus. Scientists don't yet understand how the relatively benign coronavirus mutates into the fatal FIP.

How do cats get FIP?

Coronaviruses are primarily passed on from cat to cat when they come into contact with infected feces - where they can live in normal circumstances for up to 36 hours. 

The virus can then lay dormant in a cat for years, and if they're very unlucky can mutate into FIP without warning. Thankfully, the majority of cases where cats are infected with coronavirus are harmless and do not mutate into deadly infections like FIP. 

Is FIP contagious?

FIP is relatively rare, and the mutation of the coronavirus that causes FIP is not contagious. The enteric coronavirus itself, however, is very contagious.

What are the symptoms of FIP?

A cat or kitten suffering from FIP may show a variety of different symptoms or no symptoms at all at first. The symptoms they do show will depend on whether or not they suffer from the dry (non-effusive) or wet (effusive) form of the disease. We've broken down some of the most symptoms of each type below:

• Loss of appetite
• Fever
• Weight loss
• Jaundice
• Diarrhea
• Swelling caused by a build-up of fluid in the abdomen
• Difficulty breathing

Dry (non-effusive) FIP symptoms

• Fever
• Vomiting
• Loss of appetite
• Diarrhea
• Seizures
• Nodular growths (granulomas) on their internal organs
• Neurological symptoms such as blindness and paralysis

Can I test my cat for FIP?

Today, veterinarians have access to specific techniques to enable them to detect the presence of coronavirus. However, most analyses do not distinguish between the enteric coronavirus and the coronavirus mutation that causes FIP.

When will a veterinarian run these tests?

Treatment for FIP

Unfortunately, there is currently no proven cure for FIP. There are, however, anti-viral medications in use which have had some success in helping cats with the dry (or non-effusive) form of the disease. If your cat has been diagnosed with FIP, you should talk to your vet about your options. 

Unfortunately, almost all cats who develop the disease will die, or have to be euthanized.  The only treatments veterinarians may offer are palliative and may include:

• Pain medication: to reduce pain and stress during the final stages of the disease
• Drainage: to remove built-up fluid and reduce discomfort
• Anti-inflammatories: to help reduce inflammation and pain in the short term

How long can a cat live with FIP?

A cat infected with feline coronavirus can live for years without any other infections developing. However, a cat who develops FIP is likely only to live for a very short time after they are diagnosed, due to the seriousness of the symptoms and complications they bring.

If a cat has developed wet FIP, where fluid fills the body cavity and causes problems with their breathing, they will almost always have passed within 5 weeks of their diagnosis. If they contract the dry form of FIP, they may live a few months if the virus doesn't mutate into wet FIP during this time.

What are the final stages of FIP in cats?

Once diagnosed with FIP, many veterinarians will recommend euthanizing your cat to avoid unnecessary pain. However, if the disease is allowed to develop to its later stages the symptoms are quite extreme. Cats with dry, or non-effusive FIP may be unable to walk, unable to see and may ultimately become paralyzed. For cats with (wet) FIP, you may see their abdomen expand as blood and fluid leak into their body cavities and they struggle to breathe.

When to euthanize a cat with FIP

Deciding to euthanize your cat may be one of the hardest decisions of your life. When it comes to FIP though, it may be the most humane option. Cats with FIP may go through a lot of suffering as the condition progresses. Your veterinarian will advise you when may be the best time for you to allow your cat to pass rather than live through the pain.

Is there a vaccine against FIP?

There is an available vaccine for feline infectious peritonitis, but its effectiveness remains a controversial topic.

To understand which vaccines your new kitten will require, it's important to speak to your veterinarian. They will provide recommendations based on the cat's lifestyle by analyzing a variety of factors including whether they'll go outside and be in contact with other cats.

If you're concerned about your kitten's health or have any questions about which vaccines they should have, always make sure you speak to your veterinarian.