Introduction
Feline Infectious Peritonitis (FIP) is one of the most complex and concerning diseases in feline medicine. Caused by a mutated feline coronavirus (FCoV), FIP can progress rapidly and affect multiple organs, leading to severe illness. For years, it was regarded as an incurable condition, but with the introduction of advanced antiviral therapies, effective treatment is now possible. This guide explains FIP symptoms, how the disease is diagnosed, the treatment options available, and essential prevention strategies for cat owners.
1. Recognizing Symptoms of FIP
Symptoms of FIP vary depending on whether the cat has the effusive (wet) form or the non-effusive (dry) form.
Wet (Effusive) FIP: Characterized by fluid buildup in the abdomen or chest. Cats may have swollen bellies, difficulty breathing, persistent fever, lethargy, and weight loss.
Dry (Non-Effusive) FIP: More challenging to detect. Symptoms include neurological problems such as seizures, imbalance, or paralysis; eye changes like uveitis or retinal lesions; chronic fever; and gradual weight loss.
General Signs: Poor appetite, depression, anemia, and chronic inflammation. Early symptoms may resemble other illnesses, so careful evaluation is essential.
2. How FIP Is Diagnosed
There is no single definitive test for FIP. Instead, veterinarians rely on a combination of medical history, physical examination, and laboratory findings.
Blood Tests: High globulin levels, low albumin-to-globulin ratio, anemia, and elevated white blood cell counts are common.
Fluid Analysis: In effusive FIP, fluid from the chest or abdomen is examined. FIP fluid is typically thick, yellow, and protein-rich.
Imaging: Ultrasound or X-rays can detect fluid accumulation, enlarged lymph nodes, or organ involvement.
PCR Testing: Detects coronavirus RNA, though a positive result does not always mean FIP.
Clinical Evaluation: Veterinarians combine test results with clinical signs to reach a presumptive diagnosis.
3. Treatment Options for FIP
The biggest breakthrough in FIP treatment has been the development of antiviral drugs that inhibit viral replication.
GS-441524: A nucleoside analog proven highly effective in blocking viral replication. Survival rates in treated cats now exceed 80–90%.
Pronidesivir (NeoFipronis®): An oral formulation of GS-441524 specifically designed for veterinary use. Easier to administer and less stressful for cats compared to injections.
Remdesivir: Used in some countries as an alternative, since it metabolizes into GS-441524 in the body.
Treatment Duration: Typically requires 12 weeks of continuous therapy, with dosages adjusted for weight and disease severity. Neurological or ocular cases require higher dosages.
4. Supportive Care During Treatment
Antivirals are the cornerstone, but supportive measures enhance recovery and improve quality of life.
Nutritional Support: High-quality, protein-rich diets help maintain body weight and strength.
Immune Support: Taurine, omega-3 fatty acids, probiotics, and vitamins support general health.
Anti-inflammatory Medications: Used selectively to reduce severe inflammation, though less critical with effective antiviral treatment available.
Symptom Management: Intravenous fluids, appetite stimulants, or antibiotics may be used as needed.
5. Monitoring and Follow-Up
During and after treatment, regular veterinary check-ups are essential.
Blood Monitoring: CBC and biochemical tests every few weeks to assess response and detect organ stress.
Weight Tracking: Weight gain indicates positive response to treatment.
Neurological Assessments: In dry FIP cases with neurological involvement, progress must be monitored closely.
Post-Treatment Surveillance: Even after completing the full course, periodic checks ensure no relapse occurs.
6. Prevention of FIP
Since not every coronavirus infection leads to FIP, prevention focuses on reducing viral load and supporting immunity.
Hygiene: Keep litter boxes clean and reduce overcrowding in multi-cat households.
Stress Reduction: Cats in low-stress environments have stronger immune defenses.
Cattery Management: Breeders must avoid high-density housing and monitor breeding lines for FIP history.
Wellness Care: Regular veterinary visits and balanced nutrition strengthen resilience against infection.
7. The Future of FIP Research
The future is optimistic. Ongoing research aims to refine antiviral drugs, develop safe vaccines, and explore combination therapies for more complex cases. With more veterinary-approved products like Pronidesivir becoming available, treatment will become more accessible and standardized.
Conclusion
FIP has transformed from a fatal disease into a treatable condition thanks to modern antiviral therapy. By recognizing symptoms early, ensuring accurate diagnosis, and committing to full-course treatment, cat owners can provide their pets with a real chance at recovery. Combined with preventive care, these advances bring new hope for cats worldwide.