🧬 What is Feline Calicivirus (FCV)?

FCV is a highly contagious RNA virus in the Caliciviridae family, responsible for a significant portion of feline upper respiratory infections, often called “cat flu” :contentReference[oaicite:3]{index=3}.

🐾 Who’s at Risk?

• Kittens, seniors, immunocompromised cats
• Cats in shelters or multi-cat households :contentReference[oaicite:4]{index=4}
• What makes FCV tricky: many strains—up to 50% of URIs involve FCV :contentReference[oaicite:5]{index=5}

⚠️ Symptoms & Unusual Signs

Classic signs include:

• Sneezing, nasal & ocular discharge
• Fever, lethargy, poor appetite
• Painful mouth ulcers/stomatitis :contentReference[oaicite:6]{index=6}

Less common:

• Limping/polyarthritis—also called “limping calicivirus” :contentReference[oaicite:7]{index=7}
• Inflammation beyond the respiratory tract (rare strains) :contentReference[oaicite:8]{index=8}
• Highly virulent systemic FCV (VS-FCV): facial swelling, edema, jaundice—up to 67% mortality :contentReference[oaicite:9]{index=9}

🧫 How is FCV Transmitted?

• Spread via saliva, eye/nose secretions—can travel meters via sneezes.
• Virus survives days to weeks in environment, especially damp areas :contentReference[oaicite:10]{index=10}.
• Carriers shed virus long-term—some after recovery :contentReference[oaicite:11]{index=11}.

🩺 Diagnosing FCV

• Physical exam with signs like ulcers and discharge
• PCR testing of swabs, virus culture confirms diagnosis :contentReference[oaicite:12]{index=12}
• Bloodwork and imaging if complications appear

💊 Treatment & Supportive Care

No cure—treatment focuses on comfort and preventing secondary infection:

• Steamy bathroom for 10–15 min twice daily :contentReference[oaicite:13]{index=13}
• Clean discharges with warm cloths
• NSAIDs for pain and inflammation :contentReference[oaicite:14]{index=14}
• Antibiotics against secondary infections :contentReference[oaicite:15]{index=15}
• Soft, warm, strong‑smelling food to stimulate appetite :contentReference[oaicite:16]{index=16}
• Fluids, hospitalization, nebulization for severe cases :contentReference[oaicite:17]{index=17}
• Joint pain treatment: corticosteroids, rest if limping occurs :contentReference[oaicite:18]{index=18}

🏥 Recovery & Long-Term Concerns

• Most recover in 1–3 weeks; mild cases resolve quicker :contentReference[oaicite:19]{index=19}
• Chronic carriers may shed intermittently :contentReference[oaicite:20]{index=20}
• Some develop chronic stomatitis or polyarthritis :contentReference[oaicite:21]{index=21}
• VS-FCV prognosis is grave—requires intensive care and isolation :contentReference[oaicite:22]{index=22}

🛡️ Prevention & Vaccination

• FVRCP vaccine includes FCV—initial series then boosters every 1–3 years :contentReference[oaicite:23]{index=23}
• Vaccine reduces disease severity, not full immunity :contentReference[oaicite:24]{index=24}
• High‑virulence strains (VS-FCV): specialized CaliciVax available :contentReference[oaicite:25]{index=25}
• Hygiene: isolate infected cats, clean fomites with bleach solution, ventilated spaces :contentReference[oaicite:26]{index=26}

📌 Practical Advice for Cat Parents

• 📅 Keep vaccines up to date
• 🧼 Clean and isolate when one cat is sick
• 💨 Use steam therapy during flare-ups
• 🍲 Offer palatable, warm soft food
• 💧 Ensure hydration—wet food/fountains
• 📱 Use Ask A Vet for ongoing advice; Woopf & Purrz products help reduce stress during illness

📝 Summary Table