Feline Infectious Peritonitis: What Every Cat Owner Needs to Know

Cats are known for their mysterious nature. Unfortunately, so is one of the most dangerous feline diseases.

Feline infectious peritonitis (FIP) is a viral disease caused by a feline coronavirus (FCoV) mutation and can lead to severe illness and death. This article will explain what you need to know about this viral threat and how to protect your cat.

Feline infectious peritonitis explained

Around the world, many cats carry the FCoV without any sign of visible illness. This virus lives within the cat’s intestines and is shed through the feces, where it can be transmitted to other cats. In a small number of cats, the feline coronavirus mutates into the virus that causes FIP. The virus then lives and multiplies within the cat’s white blood cells, creating widespread inflammation and illness throughout the cat’s body.

While FIP is most commonly seen in kittens and cats under 2 years old, older cats can also be affected.

FIP transmission

FIP itself is not contagious between cats. However, its precursor, FCoV, is spread from cat to cat through direct contact with feces, saliva, and shared items such as food bowls or litter boxes. Minimizing your cat’s exposure to areas where feline coronavirus is common, such as shelters, boarding facilities, or catteries, may lower your cat’s risk for FIP.

Is my cat sick? Recognizing the symptoms of feline infectious peritonitis

Part of FIP’s mystery is in how it presents itself. The two forms of FIP include:

• Wet or effusive FIP — Cats with wet FIP experience fluid buildup in their abdomen or chest, causing visible swelling, difficulty breathing, and tiredness.
• Dry or non-effusive FIP — Dry FIP targets the brain, eyes, liver, and kidneys. This can cause seizures, vision changes, weight loss, or urinary signs.

Wet and dry FIP often share similar symptoms that suggest general illness. These include:

• Appetite loss
• Fatigue
• Weight loss or failure to gain weight
• Fever that doesn’t respond to antibiotics

In either case, FIP symptoms are often vague. Because cats tend to hide pain and illness, many owners don’t notice the early warning signs.

Treatment for FIP

“Pet owners seeing signs concerning for possible FIP should see their veterinarian as soon as possible,” says Bryan T. Clarke, DVM, DABVP (Canine and Feline) at All Creatures Animal Hospital AAHA-accredited hospital in Lutz, Florida. “The disease can progress quickly, and earlier diagnosis and intervention are critical for improving the chances of successful treatment. Testing, including blood tests, urine tests, and diagnostic imaging such as radiographs and ultrasonography are essential to not only confirm the diagnosis but also guide treatment decisions.”

Can cats survive FIP? Until recently, it was considered untreatable. Fortunately, a new and promising antiviral treatment is available in the U.S. This medication has been used in other countries for several years and has shown success in treating FIP. However, as with any new treatment, there are risks and unknowns.

“Treating FIP was viewed as all but impossible until GS-441524 became available in the US. So, though treatment often takes 12 weeks, it’s a miracle that we can now cure this once universally fatal disease,” Dr. Clarke emphasizes.

If your cat is diagnosed with FIP, your AAHA-accredited veterinarian will discuss potential options with you. Early FIP diagnosis and intervention are key to improving your cat’s outcome, so seek prompt veterinary care if your cat shows signs of FIP.

How can I protect my cat?

Without a vaccine for FIP, there is no sure way to prevent this devastating virus. Dr. Clarke advises that the only way to prevent FIP is to avoid FCoV exposure. However, that approach isn’t practical, given how highly contagious and common the mutation is. The best strategy for prevention is to focus on maintaining a healthy environment.

“Be sure to follow your veterinarian’s recommended preventive care plan, including immunizing against other infectious diseases, providing a low-stress and clean environment for your cat, protecting them from parasitic conditions with appropriate preventive medications, and having regular physical exams performed by your veterinarian to detect any other conditions,” Dr. Clarke recommends.

To ensure you have a clean and sanitary environment, consider the following factors:

• The litter box should be spot-cleaned daily and thoroughly cleaned and sanitized at least once weekly.
• Keep the litter box away from the food and water dishes.
• Clean food dishes after every meal and water dishes using hot, soapy water daily. Deep clean and disinfect them weekly.
• Regularly wash your cat’s bedding. The frequency will depend on your cat’s habits and any underlying medical conditions.

Reduce stress by providing your cat with plenty of mental and physical stimulation. This can include environmental enrichment (like scratching posts and window perches), a variety of toys appealing to different play styles, and incorporating regular interactive playtime in your schedule.

If you have a multi-cat home, ensure that they have enough space to avoid stress from overcrowding. Most experts recommend no more than three cats per room.

Get to know your cat

Understanding your cat’s normal behaviors and habits can help you know when to visit the veterinarian. Changes in your cat’s eating, sleeping, grooming, or play habits can signal hidden illness or pain. Bringing these concerns to your AAHA-accredited veterinarian can help your cat receive timely, potentially life-saving care.

FIP is a devastating and unusual disease, but early detection, emerging treatments, and preventive care may offer hope. By staying informed and partnering with your veterinarian, you can help protect and preserve your cat’s health. If you have concerns about FIP or any aspect of your cat’s well-being, contact your AAHA-accredited veterinarian.