Feline infectious peritonitis (FIP) is a fatal disease that is observed in cats. Studies have reported that, this disease affects 5% of cats residing in catteries and multi-cat households. The incidence of this disease in households with one or two cats is 1 in 5000 and increases significantly in households with more number of cats. FIP is caused by a virus known as Feline Infectious Peritonitis Virus (FIPV). Initially, a cat gets infected by a virus known as feline coronavirus (FCoV) which has two forms, an avirulent form (unable to produce disease) and a virulent form (extremely infectious). The avirulent form is called feline enteric coronavirus (FECV) which mutates to virulent form, feline infectious peritonitis virus (FIPV) in the cat. This virulent form of virus invades macrophages or white blood cells and starts replicating, thereby, causing progression of the disease.
This disease progresses in three stages. The first stage continues for two to four weeks after the cat acquires the virus. During this stage, the cat sheds a significant amount of virus, through which other cats can also get infected. The second stage can continue for some weeks or even several years, during which the virus remains in a dormant state in the cat. Only when the cat is stressed-out, it may shed some virus or else, it remains non-communicable. The last stage begins when illness is triggered and ends with death of the cat. During this stage too, the disease does not spread to other cats.
The identification of FIP, like any other disease, is extremely important to provide treatment as soon as possible because cats cannot express their sufferings through speech. Following section deals with the identification, treatment, and prevention of this lethal and incurable disease.
How to Identify FIP in Cats
Through SymptomsThere are two forms of FIP, namely, dry form and wet form. Given below are symptoms observed in each of them.
Dry Form or Effusive FIP
- Chronic weight loss
- Loss of appetite
- Ocular signs like irregular and discolored appearance of the eye
- Neurological signs like paralysis, loss of balance, disorientation, tremors, convulsions, etc.
Wet Form or Non-effusive FIP
- Weight loss
- Loss of appetite
- Difficulty in breathing
- Fluid accumulation in chest and abdomen
Through Diagnostic Tests The diagnosis of FIP is not easy and needs a cumulative analysis of medical history, symptoms observed, and laboratory test results. The following diagnostic tests are conducted to confirm the disease in a cat.
- Blood Tests: Complete blood count is carried out to diagnose FIP. The level of hemoglobin, white blood cell count, creatinine, BUN, bilirubin, and serum proteins in the cat’s body are measured. Deviations from normal level help in confirming the disease.
- Biopsy: This is the best way to confirm FIP in cats. Affected tissues are examined by a veterinary pathologist and special tests are performed to confirm the presence of virus in collected tissue samples.
- Fluid Sample Analysis: For the confirmation of wet form of FIP, fluid samples are drawn from the chest or abdomen of the cat, and tests are performed on them.
- FCoV Test: This test detects antibodies produced in the cat’s body in response to the FCoV virus. The result is mentioned as a “titer”. Detection of antibodies even after a titer of 1:100 (1 ml of sample diluted in 100 ml of diluting agent) means that the test sample is positive. The presence of antibodies, however, does not confirm FIP in the cat.
A high titer in FCoV test could mean four things. First, the cat was infected by the virus, but has eliminated it. Second, it is still a carrier of the virus. Third, the cat is vaccinated for the disease and fourth, the cat has developed FIP. The probability of a cat having FIP is 88.9% when the test results show less number of white blood cells (1.5 x 103 cells/µl), positive FCoV test (titer > 1:60) and elevated blood globulins (> 5.1 gm/dl). In fluid sample test, if the fraction of gamma globulins is greater than 32%, there are 100% chances that the cat has developed FIP.
Treatment Options for FIP
Since there is no known cure for FIP yet, treatment provided is generally targeted to decrease the discomfort and suffering associated with it. As the dry form progresses slowly, the cat may survive for several years. But dealing with wet form is difficult, as it progresses too rapidly and ultimately leads to death of the cat in a short period of time. Treatment provided for FIP includes;
- Blood transfusions
- Fluid Therapy
- Healthy diet
- Ophthalmic solutions for ocular problems
- Draining of accumulated fluid in wet form
- Medications like immunosuppressive drugs and antibiotics
- Litter boxes must be cleaned and disinfected regularly.
- In catteries, cats must be divided in groups of 4 or 5 and kept separately.
- Items like dishes and other articles, which are suspected to be contaminated with the virus, must be kept away from cats.
- Cats suspected to have acquired the virus must be isolated from rest of the population.
- Kittens must be removed from pregnant queen cats between 4-6 weeks of pregnancy if, it is suspected to have developed FIP.
- A vaccine is available for prevention of FIP in cats. This vaccine is administered intranasally to cats which are at least 16 weeks old. It is not 100% effective and must be administered only when a veterinarian approves of it. However, the American Association of Feline Practitioners Feline Vaccine Advisory Panel does not recommend its use.
The most common mode of FECV transmission is fecal matter produced by infected cats. Healthy cats can acquire the virus either by inhalation or ingestion. Therefore, it is very important to keep infected cats separately. By carefully monitoring the signs and symptoms of FIP, cat owners can immediately contact a veterinarian for check-up so that necessary care and treatment is provided well in advance.