What Is Cat Flu?
Cat flu, also known as feline upper respiratory infection (URI) or feline respiratory disease complex (FRDC), is a highly contagious illness in cats that affects the nose, throat, and eyes.
Despite the name, cat flu is not related to human influenza. It’s caused by a combination of viruses and bacteria that impact your cat’s respiratory system.
Understanding cat flu symptoms, causes, and treatment is essential to keeping your cat healthy, especially in multi-cat homes or high-contact environments.
What Causes Cat Flu?
The most common viral causes include:
Feline herpesvirus (FHV-1)
Feline calicivirus (FCV)
Less common bacterial contributors:
Bordetella bronchiseptica
Chlamydophila felis
Mycoplasma species
How Cat Flu Spreads
Cat flu spreads easily through:
Direct contact with infected cats
Contaminated objects (food bowls, bedding, toys)
Airborne droplets from sneezing or coughing
Some cats may be carriers without symptoms and still spread the virus.
Symptoms of Cat Flu in Cats
Symptoms vary depending on severity and immune response.
Sneezing
Nasal discharge (clear or colored)
Eye discharge (clear or colored)
Red, inflamed eyes (conjunctivitis)
Ulcers in the mouth, nose, or eyes
Fever
Loss of appetite
Lethargy
Dehydration
Severe cases may include difficulty breathing and require urgent care.
Diagnosis: When to See a Vet
If your cat shows symptoms, contact your veterinarian promptly.
Diagnosis may involve:
Physical examination
Blood tests
Swabs from eyes, nose, or mouth
X-rays in more serious cases
Early diagnosis helps prevent complications and speeds up recovery.
Treatment for Cat Flu
There is no single cure. Treatment focuses on supportive care.
Antibiotics — for secondary infections
Anti-inflammatory medication — to reduce discomfort
Eye drops or ointments — for eye infections
Fluid therapy — to prevent dehydration
Nutritional support — to maintain appetite
Antiviral medications — in severe cases
Always follow your veterinarian’s guidance and monitor your cat closely.
How to Care for a Cat with Flu at Home
Keep your cat warm and comfortable
Encourage eating (warm, strong-smelling food helps)
Gently clean eye and nose discharge
Reduce stress and keep the environment calm
How to Prevent Cat Flu
Prevention is the most effective protection.
Vaccination — reduces severity and duration
Isolation — keep sick cats separate
Hygiene — clean bowls, bedding, litter boxes
Stress reduction — supports immune health
Can Indoor Cats Get Cat Flu?
Yes. Indoor cats can still be exposed through:
Vet visits or grooming environments
Contact with infected animals
Contaminated clothing or objects
Final Takeaway
Cat flu is common, contagious, and sometimes serious — but manageable with early care.
Recognizing symptoms early, seeking veterinary care, and maintaining prevention can significantly improve outcomes.
If your cat shows signs of illness, seek care as soon as possible.
About the Author
Hello! I’m Dr Duncan Houston — an emergency care veterinarian, pet product designer, and pet parent to Gary, Kiko, and Bridie, a mix of big personalities with strong opinions and some of my best product testers. My work is shaped by what I see daily in practice — how animals behave under stress or boredom, what comforts them, and what truly supports their wellbeing. With over a decade in animal nutrition and product development, I founded WOOPF and PURRZ to create pet products grounded in veterinary expertise and built around natural behavior — designed to improve comfort, reduce stress, and encourage healthy play and interaction.
Frequently Asked Questions About Cat Flu
Can cat flu go away on its own?
Mild cases may improve without treatment, but many cats need supportive care.
How long does cat flu last?
Many cats improve within 7–10 days, but full recovery can take several weeks.
Is cat flu contagious to humans?
No. It does not spread to humans but is highly contagious between cats.
Can vaccinated cats still get cat flu?
Yes, but symptoms are usually milder and recovery is faster.
When should I worry about cat flu?
Seek immediate care if your cat has breathing issues, refuses food, or becomes extremely lethargic.
