Cat Feline Herpesvirus: Lifelong Infection and Flares

Feline herpesvirus-1 establishes lifelong latent infection in cats, causing recurrent episodes of upper respiratory illness that are triggered by stress and significantly affect quality of life throughout a cat's lifetime.

Key Facts

Feline herpesvirus-1 (FHV-1) is one of the two primary causes of feline upper respiratory disease
After initial infection, FHV-1 establishes latent infection in the trigeminal ganglion nerve tissue
Stress including rehoming, veterinary visits, new pets, and schedule changes triggers viral reactivation
Recurrent episodes include sneezing, nasal discharge, eye discharge, and corneal ulcers
FHV-1 corneal ulcers can cause significant pain and, if severe, permanent vision damage
Vaccines against FHV-1 do not prevent infection but reduce severity and duration of clinical signs
Lysine supplementation was once widely recommended but research now questions its efficacy

Welfare Considerations

Cats with FHV-1 experience recurrent episodes of respiratory illness that are triggered by the stresses of everyday life. Each rehoming event, veterinary visit, or household change may trigger a symptomatic flare. Corneal ulcers, when they occur, are genuinely painful - the cornea is densely innervated and ulceration causes a squinting, light-sensitive discomfort that persists until healing. Cats with recurrent flares spend significant portions of their lives managing illness that compromises their quality of life. Shelter cats are particularly burdened because the stress of shelter admission frequently triggers reactivation. The lifelong nature of herpesvirus infection means welfare management is a permanent consideration for affected cats.

What You Can Do

Minimize unnecessary stressors for cats with known FHV-1 to reduce flare frequency
Use Feliway diffusers during unavoidable stressful events including veterinary visits and moves
Seek veterinary care promptly for corneal ulcers to prevent permanent vision damage
Discuss famciclovir antiviral treatment with your vet for cats with severe or frequent flares
Maintain current vaccination status as it reduces severity of FHV-1 episodes even in already-infected cats