Hepatitis E FAQs for Health Professionals
Index of Questions
Overview and Statistics
What is Hepatitis E?
Hepatitis E is a liver disease caused by the Hepatitis E virus (HEV). HEV infection usually results in a self-limited, acute illness. It is widespread in the developing world. Although rare in developed countries, locally acquired HEV infection can result in acute hepatitis with tendency to progress to chronic hepatitis mainly among solid organ transplant recipients.
How common is Hepatitis E in the United States?
Hepatitis E is believed to be uncommon in the United States. However, some studies have found a high prevalence of antibodies to HEV in the general population. When hepatitis E does occur, it is usually the result of travel to a developing country where Hepatitis E is endemic. Thus far a dozen cases have been reported among persons with no history of travel to HEV-hyperendemic countries. No clear exposure was identified for these domestically acquired (non-travel related) cases.
Where is Hepatitis E most common?
Hepatitis E is most common in developing countries with inadequate water supply and environmental sanitation. Large hepatitis E epidemics have been reported in Asia, the Middle East, Africa, and Central America. People living in refugee camps or overcrowded temporary housing after natural disasters can be particularly at-risk. Increasingly, sporadic Hepatitis E cases not associated with travel have been identified in developed countries. The unique characteristics of HEV is that it displays different epidemiological and clinical characteristics between developing and developed countries.
Transmission and Exposure
How is the Hepatitis E virus spread?
Hepatitis E virus is usually spread by the fecal-oral route. The most common source of infection is fecally contaminated drinking water. In developed countries sporadic outbreaks have occurred following consumption of uncooked/undercooked pork or deer meat. Consumption of shellfish was a risk factor in a recently described outbreak.
Can the Hepatitis E virus be spread by animals?
There is a possibility of zoonotic spread of the virus. HEV RNA had been extracted from meat and organ of some animal species including pigs, boar, and deer. Foodborne infection could occur from consumption of uncooked/undercooked products from infected animals.
What are the signs and symptoms of Hepatitis E?
When they occur, the signs and symptoms of Hepatitis E are similar to those of other types of acute viral hepatitis and can include:
- Loss of appetite
- Abdominal pain
- Dark urine
- Clay-colored stool
- Joint pain
The ratio of symptomatic to asymptomatic infection in outbreak settings is reported to range from 1:2 to 1:13.
Who is most likely to have symptomatic HEV infection?
Symptomatic illness following HEV infection acquired sporadically or during outbreak in developing countries commonly occur among older adolescents and young adults (aged 15–44 years). Children infected with HEV usually have mild or no symptoms. Pregnant women are more likely to experience severe illness including fulminant hepatitis, and death. Hepatitis E in developed countries commonly affects older men (>45 years of age).
How soon after exposure will symptoms appear?
When symptoms occur, they usually develop 15 to 60 days (mean: 40 days) after exposure.
How long does an HEV-infected person remain infectious?
The period of communicability has not been clearly determined, but virus excretion in stool has been demonstrated up to 14 days after the onset of jaundice.
How serious is Hepatitis E?
Most people with Hepatitis E recover completely. The overall case-fatality rate is about 1%. However, for pregnant women, Hepatitis E can be a serious illness with mortality reaching 10%–30% among pregnant women in their third trimester of pregnancy. Hepatitis E could also be serious among persons with preexisting chronic liver disease resulting in decompensation and mortality.
Can Hepatitis E become chronic?
To date, there is no report of progression of acute hepatitis E to chronic Hepatitis E in developing countries. However, more and more cases of Hepatitis E with progression to chronic hepatitis and chronic liver disease are being reported among cases acquired in the developed countries. These chronic cases are exclusively among persons who are on immunosuppressive treatment for solid organ transplant.
Diagnosis and Treatment
How is Hepatitis E diagnosed?
Because cases of Hepatitis E are not clinically distinguishable from other types of acute viral hepatitis, diagnosis can be confirmed only by testing for the presence of antibody to Hepatitis E or HEV RNA. No serologic tests to diagnose HEV infection have been approved by FDA for use in the United States. Several tests are available for research purposes and some commercial laboratories use commercially available assays in other countries.
HEV infection should be considered in any person with symptoms of hepatitis who has traveled to an Hepatitis E endemic region, recently travelled from an endemic area, or from an outbreak afflicted region and who is negative for serologic markers of Hepatitis A, B, C, and other hepatotropic viruses. A detailed history regarding sources of drinking water, uncooked food, and contact with jaundiced persons should be obtained to aid in diagnosis. There are increasing numbers of domestically acquired cases of hepatitis E and diagnosis should be suspected when no etiology can be identified on thorough evaluation.
How is Hepatitis E treated?
Hepatitis E usually resolves on its own without treatment. There is no specific antiviral therapy for Hepatitis E. Physicians should offer supportive therapy. Patients are typically advised to rest, get adequate nutrition and fluids, and avoid alcohol. Hospitalization is sometimes required in severe cases and should be considered for pregnant women.
How is Hepatitis E prevented?
Prevention of Hepatitis E relies primarily on good sanitation and the availability of clean drinking water. Travelers to developing countries can reduce their risk for Hepatitis E by not drinking unpurified water. Boiling and chlorination of water will inactivate HEV. Immune globulin is not effective in preventing Hepatitis E.
Is there a vaccine for Hepatitis E?
No FDA-approved vaccine for Hepatitis E is currently available in the United States.