Herpes simplex virus.

Abstract

1. Linda A. Waggoner-Fountain, MD* 2. Leigh B. Grossman, MD† 1. *Assistant Professor of Pediatrics, Division of Infectious Diseases 2. †Professor of Pediatrics and Head, Division of Infectious Diseases, University of Virginia School of Medicine, Charlottesville, VA After completing this article, readers should be able to: 1. Describe the epidemiology of herpes simplex virus (HSV) and the distinctive epidemiologic features of HSV type 1 and type 2. 2. Characterize the pathogenesis, diagnosis, treatment, and outcome of HSV infections in the neonate. 3. Explain the variety of clinical manifestations and methods of diagnosis of HSV infections in older children and adolescents. 4. Discuss the appropriate potential prevention and therapy of HSV infections in infants, children, and adolescents. Herpes simplex infections have various presentations, depending on the immune status, the age of the host, and the route of transmission. Herpes simplex viruses (HSVs) are enveloped, double-stranded DNA viruses. The two serotypes of HSV are classified as HSV-1 and HSV-2. Infections with HSV-1 usually involve the face and skin “above the waist,” although HSV-1 also can cause genital infection. Infections with HSV-2 usually involve the genitalia and skin “below the waist” in sexually active adolescents and adults. Most HSV disease in neonates is due to HSV-2. HSV-2 also causes oral lesions in approximately 25% of the infected population. Throughout this article, we categorize HSV disease by the specific host. ### Neonatal The incidence of neonatal HSV infection is estimated at 1 per 3,000 to 20,000 live births. Between 20% and 40% of infants infected with HSV are born preterm. In the United States, approximately 75% of neonatal infections are due to HSV-2, with the remainder due to HSV-1. HSV infection develops in 33% to 50% of exposed infants born vaginally to mothers who have primary genital infection. The risk to an infant born to a mother shedding HSV as a result of reactivated infection is much lower (0 to 5%). More than 75% of infants who acquire HSV infection have been born to women who had no signs or symptoms suggestive of HSV infection before or …