Introduction

Feline herpesvirus (FHV) infection, also called feline viral rhinotracheitis (FVR), is an acute upper respiratory tract disease that affects both domestic and wild cats. FHV is highly contagious among cats and tends to attacks animals with weakened immune function. It is most frequently diagnosed in multi-cat households and in cats kept in crowded, unsanitary conditions.

Symptoms of Feline Herpesvirus Infection

The most common initial sign of FHV infection is the sudden onset of sneezing fits, accompanied by eyelid spasms or squinting (blepharospasm), conjunctivitis (inflammation and redness of the membrane lining the inner surface of both eyelids) and ocular discharge. Nasal discharge and inflammation of the mucous membrane of the nose (rhinitis) is also quite common. These initial symptoms frequently are closely followed by anorexia, fever, cough, overall malaise and, if the affected feline is pregnant, abortion. The clinical signs of feline herpesvirus infection can resemble flu-like symptoms, and for this reason FHV infection is sometimes referred to as “feline influenza.” The initial symptoms generally last for about one week.

After the initial signs of feline herpesvirus infection resolve, many cats develop secondary bacterial or other infections. These infections tend to localize to the eyes, nose and mouth and can persist for weeks. Corneal ulceration can also occur. Many of these infections wax and wane, usually recurring during times of stress or immunosuppression. Others become chronic and can stabilize or worsen with time. Like other herpesvirus infections, FHV typically remains latent in an infected cat’s system for life. Future outbreaks of clinical disease may or may not occur. Cats that become pregnant or experience other stressful medical, emotional or environmental conditions, are predisposed to recurrence of clinical disease.