Hepatitis E virus

From IDWiki
(Redirected from Hepatitis E)

Background

Microbiology

  • Refers to viruses in the Hepeviridae family of RNA viruses
    • Genus Orthohepevirus, which infects terrestrial mammals and contains species A-D
      • HEV-A is the main human pathogen
        • Genotypes 1 and 2 only infect humans
        • Genotypes 3 and 4 circulate in pigs but can infect humans
      • HEV-C circulates in rodents and ferrets
    • Genus Piscihepevirus, which infects the cutthroat trout and is not of clinical interest
  • Four genotypes, g1 through g4

Epidemiology

  • Present globally
  • g1 and g2 are more common in developing countries
    • Cause epidemic hepatitis
    • Transmitted fecal-orally
    • Associated with contaminated water and poor sanitation
  • g3 and g4 more common in the North America and Europe
    • Zoonoses associated with pigs; humans are incidental hosts
    • Most severe infections in pregnant women
  • May also be transmitted by transplant or transfusion

Clinical Manifestations

  • Incubation period of about 4 to 6 weeks
  • Flu-like prodrome lasting 1 to 10 days with a low-grade fever, followed by hepatitis
  • May develop pale stools, dark urine, and jaundice
  • Hepatomegaly and sometimes splenomegaly
  • Liver enzyme abnormalities, over 1000 initially, and hyperbilirubinemia
  • Usually self-limited, but some patients progress to fulminant hepatitis
  • In immunocompromised patients, may lead to chronic infection and cirrhosis
  • Particularly high mortality rate in pregnant women (25% in third trimester)