Reovirus Infections in Cats: Vet Guide 🐱🩺 2025

By Dr Duncan Houston BVSc, veterinarian & founder of Ask A Vet.

Reoviruses belong to the family Reoviridae and commonly affect the gastrointestinal and respiratory systems of cats. Often called “respiratory-enteric orphan viruses,” these pathogens usually cause mild disease—but in kittens, seniors, or immune-compromised cats, they can trigger more serious symptoms like pneumonia, dehydration, or neurological signs. This guide aims to help you:

• 🔍 Understand what feline reovirus is
• 🌡️ Learn how it spreads, and which cats are at risk
• 🚨 Recognize clinical signs affecting GI, respiratory, and neurologic systems
• 🧪 Navigate diagnostic testing
• 💊 Provide supportive care strategies
• 🛡️ Implement prevention and hygiene protocols
• 🤝 Use Ask A Vet telehealth to support recovery

🔭 What is Feline Reovirus?

Reoviruses are non-enveloped, double-stranded RNA viruses classified under Reovirales—named for their ability to infect the Respiratory and Enteric tracts and originally called "orphan viruses" due to historically unknown disease associations :contentReference[oaicite:2]{index=2}. Cats may harbor orthoreovirus, causing either mild GI, upper respiratory, or systemic disease.

🌍 Transmission & Risk Factors

• 🦠 **Fecal–oral route:** ingestion of contaminated food, water, or litter :contentReference[oaicite:3]{index=3}
• 💨 **Aerosolized droplets:** inhaling virus-laden particles :contentReference[oaicite:4]{index=4}
• 🏠 **High-risk environments:** crowded shelters or multi-cat homes :contentReference[oaicite:5]{index=5}
• ⚠️ **Susceptible cats:** kittens, seniors, immunocompromised, or those with stress/other infections :contentReference[oaicite:6]{index=6}

🚨 Clinical Signs

The disease manifests variably depending on organ system involvement:

1. Gastrointestinal

• Diarrhea, often watery :contentReference[oaicite:7]{index=7}
• Vomiting leading to dehydration :contentReference[oaicite:8]{index=8}
• Weight loss, lethargy

2. Respiratory

• Sneezing, nasal discharge
• Coughing, mild fever and mucus membrane congestion :contentReference[oaicite:9]{index=9}
• Conjunctivitis (red eyes, eye rubbing) :contentReference[oaicite:10]{index=10}

3. Neurological

• Loss of balance (ataxia)
• Muscle tremors
• Difficulty walking, occasionally seizures :contentReference[oaicite:11]{index=11}

Most healthy adult cats experience mild illness, but young or immunocompromised felines may develop respiratory distress or severe dehydration requiring aggressive care. :contentReference[oaicite:12]{index=12}

🧪 Diagnosis

• Physical exam & history: assess signs and exposure risk.
• Fecal/respiratory PCR or viral culture: confirms reovirus.
• Bloodwork: CBC/chemistry may show dehydration or mild inflammation.
• Urinalysis: rule out kidney involvement.
• Imaging: X-rays or chest ultrasound for pneumonia or gut changes.
• Neurologic exam: if ataxia or tremors are present.

💊 Treatment & Supportive Care

No specific antiviral exists for reovirus—care is supportive:

• 💧 **Fluid therapy:** IV or SC fluids with electrolytes to combat dehydration.
• 🍲 **GI support:** Bland diet or prescription GI formulas; antiemetics like maropitant or ondansetron.
• 🧊 **Respiratory relief:** Steam therapy, humidification, and bronchodilators if wheezing.
• 😴 **Warmth & rest:** Especially for weak kittens or febrile cats.
• 😍 **Ocular care:** Clean discharge, apply lubricants or topical antibiotics for conjunctivitis.
• 💊 **Antibiotics:** Only if secondary bacterial infections are suspected.

Most uncomplicated cases resolve in 7–14 days. Monitor hydration and respiratory signs—hospitalization may be necessary in severe cases. :contentReference[oaicite:13]{index=13}

🛡️ Prevention & Hygiene

• 🧼 Clean litterboxes and bowls daily using disinfectants effective against non-enveloped viruses (e.g., accelerated hydrogen peroxide).
• 🚫 **Isolate sick cats** until symptoms fully resolve.
• 🧴 Maintain good ventilation and minimize crowding in multi-cat environments.
• 💧 Provide clean, fresh water and spilled runoff cleanup to prevent fecal-oral spread.
• 👍 Reduce stress via enrichment, routine, and minimal environmental change.

📆 Prognosis

• 👍 **Healthy adults:** excellent recovery.
• ⚠️ **Kittens/seniors:** guarded prognosis—depends on severity and hydration care.
• 🫁 **Respiratory cases:** may need extended hospitalization if pneumonia develops.
• 🔄 **Follow-up:** Recheck hydration, weight, and respiratory signs post-recovery.

🤝 Ask A Vet Telehealth Support

Ask A Vet can assist you in:

• 📱 Evaluating signs and deciding on home vs hospital care.
• 💉 Guiding home fluid administration and diet management.
• 📈 Monitoring respiratory and GI recovery remotely.
• 🏠 Advising on isolation setup and environmental disinfection.
• 📞 Helping you recognize when escalation to in-clinic care is necessary.

✅ Key Takeaways

• Reovirus causes mild GI or respiratory illness in most adult cats.
• Kittens, elderly, or ill cats can get sicker—watch for vomiting, diarrhea, nasal discharge, eye issues.
• No specific antiviral; supportive care is essential.
• Disinfection, isolation, and stress reduction prevent spread.
• Ask A Vet telehealth supports you from diagnosis through recovery.

📞 Final Thoughts

Though often mild, reovirus infections should be taken seriously in vulnerable cats. Quick action, gentle supportive care, and expert telehealth help from Ask A Vet ensure the best outcomes. 🐱💜

Need help giving fluids, tracking symptoms, or setting up safe isolation protocols? Visit AskAVet.com and download the Ask A Vet app today for personalized telehealth support!