Medicine & USMLE

Herpes Simplex Virus 2 (HSV2)

Viruses - DNA Viruses
  1. Herpesvirus Overview
  2. Herpes Simplex Virus 1 (HSV1)
  3. Herpes Simplex Virus 2 (HSV2)
  4. Varicella-Zoster Virus (HHV3)
  5. Epstein-Barr Virus (HHV4)
  6. Cytomegalovirus (HHV5)
  7. Human Herpesviruses 6 and 7 (HHV6 and HHV7)
  8. Human Herpesviruses 8 (HHV8)
  9. Poxvirus
  10. Hepadnavirus
  11. Adenovirus
  12. Papillomavirus (HPV)
  13. Polyomavirus
  14. Parvovirus

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