Feline Infectious Peritonitis (FIP) is a viral disease that affects cats worldwide. Over the past few years, significant advancements have been made in the diagnosis and treatment of this previously fatal condition. In this article, we will delve into the causes, symptoms, prevention, treatment, and care of FIP in cats.
Understanding FIP
FIP is caused by a virus known as feline coronavirus (FCoV). Coronaviruses are a common group of viruses that typically infect the upper respiratory or gastrointestinal tract of animals. However, the coronavirus causing FIP is specific to cats and does not affect humans.
Coronavirus infection is widespread among cats, especially in multi-cat households or colonies. It is estimated that 25-40% of household pet cats have been infected with FCoV, while the infection rate increases to 80-100% for cats living in close proximity to each other.
Most cats infected with FCoV show no signs or only experience mild diarrhea that resolves without treatment. However, in some cases, the virus mutates inside a cat, leading to the development of FIP. It is important to note that finding the coronavirus in a cat does not necessarily mean they have FIP, as it is challenging to differentiate between the two without further analysis.
When a cat develops FIP, the virus spreads throughout their body and interacts with their immune system, causing a wide range of clinical signs.
Signs and Symptoms of FIP
FIP can manifest in various ways, depending on which organs are affected and how the immune system responds. The early signs of FIP are often vague and include fluctuating fever, lethargy, and reduced appetite. These nonspecific symptoms can also be observed in other diseases, making FIP challenging to diagnose.
There are two main forms of FIP: wet (effusive) and dry. However, it’s important to note that cats with FIP often exhibit a combination of both forms or experience different presentations at different times.
In the wet form of FIP, fluid accumulates in the abdominal or chest cavity due to inflammation and damage to blood vessels caused by FIPV (FIP virus). This fluid accumulation leads to abdominal distension and breathing difficulties. The fluid is typically thick and bright yellow in color, containing a high protein content.
The dry form of FIP involves the formation of granulomas (masses of virus and inflammatory cells) in various organs, including the eyes, brain, liver, kidneys, lungs, and skin. Consequently, cats with dry FIP may display neurological symptoms, bleeding in the eyes, and vague signs of disease associated with lesions in internal organs.
Diagnosing FIP
Diagnosing FIP is challenging due to the lack of specific clinical signs and a simple blood test for confirmation. However, certain factors increase the likelihood of FIP, such as compatible clinical signs, higher risk categories (e.g., younger cats, colony cats), and specific changes in routine blood tests.
Routine blood tests may reveal lymphopenia (low lymphocyte count), neutrophilia (increased neutrophil count), anemia, elevated globulin concentrations, elevated liver enzymes, and elevated bilirubin. While these changes are not exclusive to FIP, the presence of multiple abnormalities, along with appropriate signs, increases the likelihood of FIP.
Obtaining a sample of fluid from the abdomen or chest cavity can be extremely helpful in diagnosing FIP. The fluid analysis reveals a high protein content and can provide further insights into the types of cells and proteins present. Additional tests, such as PCR and immunostaining, can be performed on fluid samples, needle samples, biopsies, and other tissues to detect the presence of the FIP virus.
Novel Treatments for FIP
In the past, FIP was considered fatal for most cats. However, significant developments in treatment have emerged in recent years. Studies have shown that antiviral drugs can be effective in curing FIP. Two antiviral drugs, remdesivir and GS-441524, have become legally available in several countries since 2021. These drugs have shown promising results in treating FIP, with response rates of approximately 85%.
The treatment course for FIP is long, lasting 84 days. Most cats can be treated at home with tablets or liquid medication, while severely ill cats may require initial treatment in a veterinary clinic with injectable antiviral drugs. It is important to consult with a veterinarian to discuss the best treatment options for a cat diagnosed with FIP.
While relapse is possible during or after the treatment course, it is uncommon. Cats that have been successfully treated for FIP with antiviral drugs have shown long-term health improvements. Ongoing research and the availability of other antiviral medications, such as molnupiravir, offer hope for further advancements in FIP treatment.
Preventing FIP in cats
Although a commercial vaccine for FIP is available in some countries, its efficacy is limited. The vaccine can only be administered to kittens over 16 weeks of age, which means they may have already been exposed to FCoV infection by the time they can receive the vaccine. Therefore, the vaccine is primarily recommended for breeding households with a history of FIP.
Reducing the risk of FIP in breeding households involves minimizing the number of cats in a group and keeping them in small, stable groups. Adequate litter box management, stress reduction, and preventive healthcare measures are crucial in preventing FIP. Breeding from older cats and isolating queens before giving birth can also help reduce the risk of FCoV transmission to kittens.
In rescue and rehoming facilities, good hygiene practices and avoiding overcrowding are essential for minimizing the risk of FIP. Cats should ideally be housed individually or in small stable groups, and litter boxes should be regularly cleaned and disinfected.
Conclusion
Feline Infectious Peritonitis (FIP) is a complex viral disease that affects cats globally. While it remains a challenging condition to diagnose and treat, significant advancements have been made in recent years. Antiviral drugs have shown promising results in treating FIP, offering hope for affected cats and their caregivers. However, prevention and early detection remain crucial in managing FIP. By understanding the causes, symptoms, prevention strategies, and available treatments, cat owners can provide the best care for their feline companions.
Remember, if you suspect your cat may have FIP, consult with a veterinarian for an accurate diagnosis and appropriate treatment options. With ongoing research and advancements in veterinary medicine, the future holds promise for better management and outcomes for cats affected by FIP.