Feline herpesvirus, also known as feline viral rhinotracheitis, is a common viral infection in cats caused by the feline herpesvirus type 1. It primarily affects the upper respiratory system, leading to symptoms such as sneezing, nasal discharge, and conjunctivitis. The virus is highly contagious among cats, especially in crowded environments like shelters. Once infected, cats can carry the virus for life, experiencing periodic flare-ups, particularly during times of stress. Vaccination is available and recommended to help prevent severe illness and reduce the spread of the virus among feline populations.