The initial infection by herpes simplex virus is often inapparent and occurs through a break in the skin or mucous membranes, such as in the eye, throat, or genitals. Latent infection often persists at the initial site despite high antibody titers. Recurrent disease can be triggered by temperature change, emotional distress, and hormonal factors. Type 1 herpes simplex virus is usually, but not exclusively, associated with ocular and oral lesions; type 2 is usually, but not exclusively, associated with genital and anal lesions. Type 2 infection is more common. In addition to mucocutaneous infections, the CNS and occasionally visceral organs can be involved.