The Changing Epidemiology of Herpes Simplex Virus Type 1 Infection: The Associated Effects on the Incidence of Ocular Herpes

Herpes simplex virus type 1 (HSV-1) with a worldwide distribution has been reported in all human populations, resulting in a clinical spectrum of infections. Although HSV type 2 (HSV-2) is known as the most common cause of genital herpes, an increasing number of cases with genital herpes are caused by HSV-1. The present study aimed to discuss the changes in the epidemiology of HSV-1 infection including the decline in the general incidence of HSV-1 infection in childhood and the increased rate of genital herpes, caused by HSV-1. Moreover, changes in the epidemiology of ocular herpes, i.e., the reduced rate of primary ocular herpes in children and increased incidence of ocular HSV infection in adults, were discussed.