Feline Herpesvirus (FVR)

Feline herpesvirus (FHV-1), also called feline viral rhinotracheitis, is the leading cause of the sneezing, snuffly 'cat flu' that sweeps through shelters, catteries and multi-cat homes. It is extraordinarily common — the majority of cats are exposed at some point — and it has one defining feature: once a cat is infected, the virus never truly leaves. It retreats into the nerve tissue and lies dormant, ready to reactivate when the cat is stressed, unwell, or immune-suppressed.

An acute infection looks much like a heavy human cold: bouts of sneezing, a runny nose, watery eyes and a general dip in appetite and energy. In herpesvirus, though, the eyes often bear the brunt. Conjunctivitis, squinting and, in more serious cases, ulcers on the surface of the eye are all hallmarks, and repeated flare-ups can cause lasting damage if not treated. Kittens are especially vulnerable and can become seriously ill.

Because the virus itself cannot be eliminated, care focuses on supporting the cat through each episode and reducing how often flares occur. Keeping the eyes and nose clean, tempting a congested cat to eat with strong-smelling warm food, and treating secondary bacterial infections all help enormously. Reducing stress — stable routines, calm introductions, and not overcrowding cats — is one of the most effective long-term strategies, since stress is the classic trigger for reactivation.