Herpes Simplex Virus 2 (HSV2)

Key Points

Herpes simplex virus 2 (HSV-2)

• Characteristics
  • Member of Herpesvirus family
    • Also known as human herpesvirus 2 (HHV-2)
    • Enveloped DNA virus with double-stranded, linear DNA 
      • Herpesviruses are unique in that they get their envelope by budding from nuclear membrane of host cell
• Transmission
  • Contact with infected lesions
    • Sexual transmission
      • May be prevented with condom use
    • Perinatal contact is also possible
• Pathophysiology and Presentation
  • Viral infection manifests as grouped vesicles on erythematous base
    • Can ulcerate, leading to lesions in various states of healing (vesicles, pustulations, ulcers, scabbing, etc.)
  • Primary infection
    • Herpes genitalis (genital ulcers)
      • Associated with fever, dysuria (pain with urination), inguinal lymphadenopathy
      • May occur in neonates
        • From exposure to infected genitalia of mother
  • Dormancy in sensory ganglia
    • Enters sensory nerve and moves via retrograde transport from genitals
    • Commonly in sacral ganglia
  • Reactivation
    • Replicates in ganglia with anterograde transport to epithelial cells, where virus continues to replicate
    • Same symptoms as primary infection; but less severe
    • Extragenital manifestations are rare
      • Viral meningitis more common in HSV-2 than HSV-1
• Diagnosis
  • PCR and viral culture is gold standard
  • Tzank smear of lesions
    • Epithelial cells scraped from lesion, prepared on Wright-Giemsa stain
    • Multinuclear giant cells
      • intranuclear inclusions (Cowdry type A bodies)
• Treatment
  • Acyclovir and related drugs (famciclovir/valacyclovir)
    • Guanosine analog that inhibit viral DNA polymerase (viral DNA synthesis)
    • Requires herpes viral thymidine kinases (phosphorylation) for conversion into their active form