Hepatitis E virus infection
Hepatitis E virus is a fecal-oral or foodborne RNA virus with four genotypes that usually causes self-limited acute hepatitis resembling hepatitis A, but carries a high mortality risk in pregnant patients and can become chronic in immunocompromised hosts, especially solid-organ transplant recipients. Diagnosis rests on HEV IgM or RNA, treatment is supportive for acute disease and ribavirin for chronic infection, and prevention is safe water and thoroughly cooked pork or venison.
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What this article covers
- Overview
Hepatitis E virus (HEV) is an RNA virus with worldwide distribution and four genotypes, causing acute hepatitis that clinically resembles hepatitis A in most patients.
- Epidemiology
Genotypes 1 and 2 predominate in developing countries (including India, Pakistan, Mexico, and Southeast Asia) with fecal-oral, water-related transmission, and can cause large epidemics, typically affecting young adults.
- Risk factors
For genotypes 1/2 disease: residence in or travel to a developing region with contaminated water, particularly during outbreaks affecting young adults.
- Pathophysiology
Transmission and severity vary by genotype: genotypes 1 and 2 spread through contaminated water and predominantly affect young adults in developing countries; genotypes 3 and 4 are zoonotic…
- Clinical features
Typical presentation resembles hepatitis A but with a longer incubation: jaundice, malaise, nausea, vomiting, anorexia, and right-upper-quadrant pain.
- Differential diagnosis
Hepatitis A virus infection: clinically similar but shorter incubation (15 to 50 days versus 2 to 5 weeks), never chronic even in immunocompromised hosts, and does not carry the same…
- Diagnosis
Acute hepatitis E is confirmed by HEV IgM or HEV RNA, obtained in a patient with an acute hepatitis picture and a compatible exposure (contaminated water in an endemic region, undercooked pork or…
- Management
Initially, for uncomplicated acute hepatitis E in an immunocompetent host, treatment is supportive: rest, hydration, and avoidance of hepatotoxic substances (alcohol, unnecessary medications); recovery is expected within 4 to 6 weeks.
- Complications
Fulminant hepatic failure in pregnancy: the most severe recognized complication, disproportionately affecting the third trimester and carrying substantial mortality; mandates urgent evaluation and…
- Prognosis
Generally excellent in immunocompetent, non-pregnant hosts, with recovery expected in 4 to 6 weeks.
- Prevention
Avoid untreated water in HEV-endemic regions (genotypes 1/2 risk), including for drinking, ice, and washing produce, when traveling to or residing in developing regions with epidemic HEV activity.
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Related articles
- Hepatitis A virus infection
Hepatitis A virus is a fecal-oral RNA virus that causes acute, host-immune-mediated hepatitis with a prodrome followed by jaundice, aminotransferases often exceeding 1,000 U/L, and full recovery in at least 90% of patients within 3 to 6 months. Diagnosis rests on HAV IgM, treatment is supportive, and prevention centers on a 2-dose inactivated vaccine plus prompt postexposure prophylaxis.
- Hepatitis B virus (HBV) infection
Hepatitis B virus is a bloodborne and sexually transmitted DNA virus that causes acute hepatitis and, when infection becomes chronic, progresses through immune-tolerant, immune-active, immune-control, and reactivation phases toward cirrhosis and hepatocellular carcinoma. Diagnosis rests on hepatitis B serology, chronic infection is treated with entecavir or tenofovir, and reactivation during immunosuppression is prevented with prophylactic antiviral therapy.
- Hepatitis C virus (HCV) infection
Hepatitis C virus is a bloodborne RNA virus, transmitted mainly by injection drug use, that produces mostly asymptomatic acute infection and chronic infection in 60% to 80% of cases. Diagnosis is by HCV antibody followed by HCV RNA, and direct-acting antiviral regimens cure more than 90% of patients, reducing but not eliminating the risk of cirrhosis and hepatocellular carcinoma.
- Hepatitis D virus (delta) infection
Hepatitis D virus is a defective RNA virus that can only infect a person who also has hepatitis B, producing either simultaneous HBV-HDV co-infection, which can resolve, or superinfection of pre-existing chronic HBV, which carries a high risk of fulminant hepatitis and chronic liver disease. Diagnosis requires HBsAg positivity plus HDV IgG, treatment of progressive disease is 12 months of pegylated interferon with 25% to 45% cure, and definitive prevention is hepatitis B vaccination.