What disease is FHV in cats?

FHV is short for feline herpesvirus, the pathogen of feline rhinotracheitis (cat flu), so FHV generally refers to cat flu. Many cats carry the herpesvirus, but not all infected cats show symptoms. Usually only when a cat’s resistance is low does the virus become active and cause clinical signs such as increased eye discharge, conjunctivitis, corneal dissolution, or respiratory symptoms like sneezing and coughing. Feline herpesvirus is highly contagious; if one cat in the household is infected and shows symptoms, failing to isolate it promptly can easily spread the infection to other cats.