Cat flu in cats
Everything about cat flu: causes, symptoms, treatment and prevention. A contagious respiratory infection that mainly affects kittens and weak cats.
Cat flu (feline upper respiratory infection) is a viral respiratory infection in cats. It is not related to human flu—cats cannot catch human colds and vice versa. About 90% of cases are caused by herpes and calicivirus.
🦠 Causes
The main causes of cat flu:
- • Feline herpesvirus (FHV-1) – Causes rhinotracheitis. 80–90% of cats carry herpes latently—stress can trigger an outbreak. Often recurs.
- • Feline calicivirus (FCV) – Causes mouth ulcers, sneezing and fever. Various strains exist.
- • Bacteria – Bordetella bronchiseptica and Chlamydophila felis can cause secondary infections or sometimes occur primarily.
Transmission
Via direct contact (saliva, nasal and eye discharge) or indirectly via shared bowls, bedding, toys and contaminated hands. Highly contagious between cats.
⚠️ Symptoms
Severity varies—some cats have mild symptoms, others become seriously ill:
- • Sneezing and nasal discharge (clear or coloured)
- • Watery eyes, eye discharge
- • Fever and not eating
- • Mouth ulcers and eye ulcers (especially with calicivirus)
- • Coughing and lethargy
- • Without treatment: pneumonia or lasting eye damage
Risk groups
Very young kittens, older cats and cats with weakened immune systems are at highest risk of serious complications.
💊 Treatment
There are no effective antiviral drugs for cat flu. Treatment is supportive. Most cats recover within 5–10 days with veterinary care.
- • Ensure the cat eats—scented, warm food; sometimes force-feeding needed
- • Gently clean eye and nasal discharge
- • Antibiotics for bacterial infection
- • In severe cases: hospitalization, IV fluids, oxygen
Carrier status
Cats who have had cat flu can remain carriers. Herpesvirus stays latent in the nervous system—stress, illness or medication can trigger a new outbreak. Keep infected cats isolated until fully recovered (usually 2 weeks).
🛡️ Prevention: FVRCP vaccination
The FVRCP vaccination is a core vaccine for all cats. It protects against feline viral rhinotracheitis (herpes), calicivirus and feline distemper (panleukopenia).
Kittens: first vaccination at 6–8 weeks, boosters every 3–4 weeks until 16 weeks. Adult cats: booster every 1–3 years depending on vaccine. Ask your vet for the right schedule.
🩺 This information is general. Contact your veterinarian for a consultation and tailored advice.
More about health
View our health guide for vaccinations and more.
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