Microbiology · RNA hepatitis viruses
Hepatitis E virus !
- Virus
- Non-enveloped (naked)
- Contact
- Exam priority: medium
A virus spread through contaminated water or undercooked meat. It usually clears on its own, but in pregnancy it can cause severe liver failure.
Updated 2026-11-01
Also called: HEV
At a glance
- Shape
- Icosahedral
- Genome
- Single-stranded, positive-sense RNA
- Envelope
- Non-enveloped (naked)
- Family
- Hepeviridae, genus Paslahepevirus
- Size
- About 27 to 34 nm
Morphology
- Naked capsid in stool; in blood it circulates wrapped in cell membrane (quasi-enveloped)
- Four main genotypes infect humans
Transmission
- Faecal-oral, mainly through contaminated drinking water (genotypes 1 and 2)
- Zoonotic: undercooked pork, wild boar or deer meat (genotypes 3 and 4)
- Transfusion and vertical spread, less often
Reservoir: Humans (genotypes 1 and 2); Pigs and other mammals (genotypes 3 and 4)
Isolation precautions
What the care team adds to standard precautions.
- Contact
- Gown and gloves; dedicated equipment. For C. difficile, soap-and-water hand washing.
Virulence factors
- Immune-mediated liver damage
- In pregnancy, higher risk of acute liver failure through mechanisms still under study
- In immunosuppressed people genotype 3 can persist and cause fibrosis
Diseases it causes
- Acute hepatitis E; severe in pregnancy and chronic in transplant recipients Viral hepatitis →
Clinical picture
- Self-limited acute hepatitis similar to hepatitis A
- In the second and third trimesters: acute liver failure, fetal loss and maternal death
- Chronic infection in immunosuppressed transplant recipients
- Possible neurological features, such as Guillain–Barré syndrome
Diagnosis
- Anti-HEV IgM in blood
- RT-PCR on blood or stool, useful in chronic cases or low-endemic areas
Treatment
Supportive care in the acute form. In chronic infection after transplant, immunosuppression is reduced and ribavirin may be used.
Drug class only; doses and regimens are set by the clinician from the current guideline.
Prevention
- Safe water and sanitation
- Thorough cooking of pork and game
- A vaccine is approved in a few countries (not available in Colombia)
Test yourself
Think of the answer, then tap the question to see it.
In which patients does hepatitis E carry the highest mortality?
Pregnant women, especially in the third trimester, through acute liver failure.
Which hepatitis E genotypes are zoonotic?
Genotypes 3 and 4, acquired from undercooked pork or other mammal meat.
Who can develop chronic hepatitis E?
Immunosuppressed people, above all organ transplant recipients.
Related
Related conditions
← Back to the group: RNA hepatitis viruses
Educational content on microorganisms; not a treatment guide and no substitute for a health professional's advice. No doses are given.
Sources: Hepatitis E (World Health Organization (WHO), 2025); Appendix A: Type and Duration of Precautions Recommended for Selected Infections and Conditions (CDC, 2024).
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Representative model, for educational purposes only.