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  • Herpes simplex viruses (HSVs) are common human DNA viral pathogens that intermittently reactivate. After replication in the skin or mucosa, the virus infects the local nerve endings and ascends to the ganglia where it becomes latent until reactivation.

  • There are two types of HSV: HSV-1 and HSV-2. HSV-1 is mostly associated with orofacial disease, whereas HSV-2 usually causes genital infection, but both can infect oral and genital areas and cause acute and recurrent infections.

  • Most of the adult population is seropositive for HSV-1, and the majority of infections are acquired in childhood. About one-fourth of adults are infected with HSV-2 in the United States. Acquisition of HSV-2 correlates with sexual behavior.

  • Most primary HSV infections are asymptomatic or not recognized, but they can also cause severe disease. Most recurrences are not symptomatic and most transmissions occur during asymptomatic shedding.

  • Genital herpes is the most prevalent sexually transmitted disease worldwide and is the most common cause of ulcerative genital disease; it is an important risk factor for acquisition and transmission of HIV.

  • HSV can cause diseases involving the eye, CNS, and neonatal infection. Cellular immunity defects are a risk factor for severe and disseminated disease.

  • Diagnosis is made by polymerase chain reaction, viral culture, or serology, depending on the clinical presentation.

  • Treatment is with acyclovir, valacyclovir, or famciclovir. Regimens and dosages vary with the clinical setting. Resistance is rare, other than in immunocompromised patients.

Herpes simplex virus (HSV) infections are common worldwide and are caused by 2 closely related types of HSV. Their main clinical manifestations are mucocutaneous infections, with HSV Type 1 (HSV-1) being mostly associated with orofacial disease, and HSV Type 2 (HSV-2) usually being associated with genital infection. HSV-1 is increasingly becoming a more common cause of genital mucosal infections in young women in the United States than HSV-2.1


The incidence of primary infection with HSV-1, which is responsible for the vast majority of recurring labial herpes, is greatest during childhood, when 30% to 60% of children are exposed to the virus. Rates of infection with HSV-1 increase with age and reduced socioeconomic status. From 20% to 40% of the population has had episodes of herpes labialis. The frequency of recurrent episodes is extremely variable, and, in some studies, averages approximately once per year. From 2005 to 2010 the seroprevalence of HSV-1 in the United States was 30% in persons 14 to 19 years of age, 50% in persons 20 to 29 years of age, and 62% in persons 30 to 39 years of age.2 The rate of HSV-1 declined by 7% from 1999-2004 to 2005-2010.

Acquisition of HSV-2 correlates with sexual behavior and the prevalence of infection in one’s potential sexual partners. Antibodies to HSV-2 are rare in people before the onset of intimate sexual activity and rise steadily thereafter. From 2005 to 2010 the seroprevalence of HSV-2 in the ...

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