Feline Herpesvirus Dermatitis

Overview

Sneezing, lethargy, anorexia, fever, conjunctivitis, lymph node enlargement and serous/mucopurulent nasal and ocular discharge. Corneal or oral ulceration may be in more severely affected cats. Some cats will develop one or more ulcers on their faces, trunk, distal extremities, and footpads.

Signs & Symptoms

Cats commonly develop sneezing, lethargy, anorexia, fever, conjunctivitis, lymph node enlargement and serous/mucopurulent nasal and ocular discharge. Corneal or oral ulceration may be in more severely affected cats. Some cats will develop one or more ulcers on their faces, trunk, distal extremities, and footpads; skin ulcerations may be crusted. Degree of itchiness varies.

Causes & Transmission

Feline herpesvirus-1 causes an upper respiratory disease and skin/oral ulceration. Transmission is via direct or indirect contact with respiratory/ocular/oral secretions.

Affected Animals

This is a common, worldwide disease of cats with highest incidence found in shelters, catteries, and boarding facilities. In adult cats, stress or immunosuppressive drugs can trigger the disease.

Complications & Prognosis

The prognosis is typically good. Most cats will recover within 3 weeks. Some cats may remain carriers or be prone to relapses. Feline herpervirus-1 is contagious to other cats, but not to dogs and humans.

Treatment

Steroids should be avoided, as they will make the viral infection worse. Secondary bacterial infections of the respiratory tract/skin/eyes should be treated with oral or ophthalmic antibiotics. Corneal ulcers may require antiviral ophthalmic eye drops. Other treatments to be considered include oral alpha-interferon and lysine supplementation, which have mild antiviral effects. More potent antiviral therapy with topical imiquimod cream and/or oral famcyclovir can be used for refractory skin ulcers.

Diagnosis

Herpesvirus can be isolated from oropharyngeal swabs or conjunctival smears. Biopsies of skin crusts and ulcers should be performed and will reveal epidermal necrosis and ulceration, superficial crusting, and mixed inflammation often with large numbers of eosinophils. Viral intranuclear inclusion bodies may be seen within epidermal cells and special immunological stains of biopsy specimens can aid in virus identification. It is important to perform appropriate testing to rule out other diseases that can cause similar symptoms. Other diseases, which can cause respiratory signs, include feline calicivirus, BordetellaChlamydia, and Mycoplasma. In the absence of respiratory signs, differentials for skin ulcerations include dermatitis due to feline leukemia, drug eruption, erythema multiforme, pemphigus vulgaris and systemic lupus erythematosus. Additionally, diseases that can cause crusty or itchy skin lesions include bacterial or fungal skin infections, skin parasites, or allergic skin disease such as food allergy or atopy.