Excerpt from Herpes Simplex

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Background

Herpes simplex virus (HSV), a large complex DNA virus, commonly infects the skin and the mucous membranes in the regions of the mouth, genitalia, and eye. Two antigenically related strains of HSV can be distinguished, type 1 and type 2. Type 1 most commonly is associated with infections of the orofacial area and the ocular surface, while type 2 causes genital disease.

Pathophysiology

Infection is spread by direct contact of skin or mucous membranes to infected secretions. The initial attack generally is self-limited and often is subclinical. However, herpetic disease is recurrent, and a wide range of clinical manifestations can result from an infection with this agent. The most common site of primary infection in humans is the skin and the mucous membrane innervated by the trigeminal nerve. The virus is transported via the nerve axon to its cell body in the sensory ganglion where it persists in a latent state until reactivation. Some indication exists that the human cornea also may harbor latent virus. Recurrent disease is the result of reactivation of this latent virus.

Frequency

United States

Of adults in the US, 50-90% have antibodies to HSV type 1, indicating previous exposure to the virus. Incidence of ocular HSV infection is approximately 0.15%.

Mortality/Morbidity

HSV keratitis is the most frequent cause of corneal blindness in the US, with reports of any visual disability as high as 40%.

Sex

This condition has a slightly higher male predominance.

Age

The mean age of presentation is in the late fifth to early sixth decade of life.

Please click here to view the full topic text: Herpes Simplex