Herpes, Genital



  • Genital herpes is a lifelong recurrent infection
  • Two types of HSV can cause genital herpes: HSV-1 and HSV-2
  • Most cases of recurrent genital herpes are caused by HSV-2
  • There is an increasing proportion of HSV-1 anogenital herpetic infections
  • ∼50 million persons in the U.S. are infected with HSV-2
  • Most reported cases involve the age groups between 16–40 yr
  • Genital herpes simplex virus (HSV) infections are designated as primary, nonprimary first episode, recurrent, asymptomatic
  • Primary HSV infection:
    • Refers to infection in a patient without preexisting antibodies to HSV-1 or HSV-2
    • Average incubation period after exposure is 4 d (range 2–12 d)
  • Nonprimary first episode:
    • Refers to acquisition of genital HSV-1 in a patient with preexisting antibodies to HSV-2 or vice versa
    • Associated with fewer lesions and less symptoms than primary infection
    • Antibodies against one HSV type offer some protection against the other
  • Recurrent HSV infection:
    • Refers to reactivation of genital HSV in which the HSV type recovered in the lesion is the same type as antibodies in the serum
    • Duration of lesions is shorter than with primary infection (10 vs. 19 d)
    • Symptoms can be less severe; genital lesions may be asymptomatic, fewer in number, atypical in appearance
    • Duration of viral shedding is shorter than primary infection (2 vs. 9 d)
  • Asymptomatic HSV infection:
    • Virus is shed intermittently and often transmitted by persons who are without lesions or symptoms
    • Asymptomatic shedding of HSV from the genital tract is most common source of transmission of infection


  • 70–90% caused by a DNA virus HSV-2:
    • Remainder caused by HSV-1
  • Infection with HSV-1 generally occurs in the oropharyngeal mucosa:
    • Trigeminal ganglion becomes colonized; harbors latent virus
    • Increasingly more common to detect evidence of HSV-1 in the genital tract, usually due to oral–genital sex
    • Recurrences of HSV-1 in the genital tract uncommon
  • Acquisition of HSV-2 infection is usually the consequence of transmission by genital contact:
    • Virus replicates in the genital, perigenital, or anal skin sites:
      • Latent virus in sacral ganglia
    • HSV-2 can also infect the mouth:
      • Recurrences at this site uncommon
  • HSV vaccines unsuccessful to date, research is ongoing
  • High association with HIV and other STDs

  • Contact isolation and universal precautions should be maintained
  • Those infected with HSV-2 are 2–3 times more likely to acquire HIV:
    • Patients who test positive for HSV-2 should also be tested for HIV

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