Feline Herpesvirus Management: A Deep Welfare Guide
Virus Biology and Latency
FHV-1 is an alphaherpesvirus that infects cats worldwide. Following primary infection (typically as a kitten), the virus establishes lifelong latency in the trigeminal ganglia. Stress triggers viral reactivation and shedding, causing recurrent clinical signs. Approximately 80% of cats that recover from primary FHV-1 infection become latently infected. Reactivation is unpredictable: major life stressors (rehoming, new cats, surgery, illness) are common triggers.
Clinical Manifestations
FHV-1 causes upper respiratory tract signs (sneezing, nasal discharge, conjunctivitis) and ocular signs (corneal ulceration, stromal keratitis, symblepharon). Chronic rhinitis and sinusitis develop when primary infection causes irreversible nasal turbinate damage. Eosinophilic dermatitis and skin ulceration are rare but reported FHV-1 manifestations. Severity varies from mild transient episodes to severe chronic disease.
Antiviral Treatment
Famciclovir (oral prodrug converted to penciclovir in cats) is the most effective and safest systemic antiviral for FHV-1 in cats. Topical cidofovir (0.5% ophthalmic solution) is effective for corneal disease. Topical ganciclovir gel is an alternative. Acyclovir is not recommended (poor bioavailability, potential toxicity in cats). Antivirals reduce severity and duration of active disease but do not eliminate latent infection.
Stress Reduction for Welfare
Minimising stress is the cornerstone of long-term FHV-1 management. Environmental enrichment, stable group composition, Feliway pheromone diffusers, and predictable routine reduce reactivation frequency. In multi-cat households, ensuring adequate resources (litter trays, feeding stations, resting spots) reduces inter-cat tension. Identifying and addressing specific stressors improves welfare outcome.
Nutritional Support and Supplements
Lysine supplementation was historically promoted to reduce arginine availability for viral replication, but current evidence does not support benefit and international feline specialist bodies no longer recommend routine supplementation. Omega-3 fatty acids support immune function. Maintaining good nutrition, dental health, and body condition supports immune surveillance. Regular veterinary monitoring of chronically affected cats allows early intervention during reactivation episodes.