Cat Chronic Upper Respiratory Disease

Feline herpesvirus and calicivirus cause chronic upper respiratory disease in many cats, particularly those from shelter or multi-cat backgrounds.

Key Facts

Feline herpesvirus (FHV-1) is lifelong once acquired; most cats become latent carriers after primary infection.
Stress is the primary trigger for FHV-1 recrudescence, causing recurrent conjunctivitis, sneezing, and nasal discharge.
Feline calicivirus (FCV) causes oral ulceration, which is acutely painful and impairs eating.
Vaccination reduces severity but does not fully prevent infection from all strains.
Multi-cat households and catteries are highest-risk environments for transmission.

Welfare Considerations

Cats with chronic upper respiratory disease experience episodes of eye and nasal discharge, discomfort, and in FCV cases, significant oral pain. Severe FHV-1 recrudescence can cause corneal ulceration and permanent eye damage. Management includes L-lysine supplementation (though evidence for efficacy is mixed), antiviral eye drops (idoxuridine or ganciclovir), and stress reduction through environmental enrichment and Feliway diffusers. Chronic carriers require careful management in multi-cat settings to prevent transmission to naive individuals. Welfare in shelter settings depends heavily on rapid identification and isolation of respiratory cases.

What You Can Do

Vaccinate cats against FHV-1 and FCV according to your vet's protocol.
Minimise stress triggers in cats with recurrent herpesvirus flare-ups.
Seek veterinary treatment promptly for eye symptoms — corneal ulcers worsen rapidly without treatment.
Implement robust respiratory disease protocols in multi-cat environments including prompt isolation.