Ehepatiidi

Ehepatiidi, or hepatitis E, is a liver disease caused by hepatitis E virus (HEV), a non-enveloped, positive-sense RNA virus in the Hepeviridae family. In humans, HEV infection is typically acquired via the fecal-oral route, most often through water contaminated with feces in areas with poor sanitation. A subset of genotypes (genotypes 3 and 4) is zoonotic and can be transmitted through consumption of undercooked pork, game meat, or shellfish in developed countries.

Epidemiology and risk factors vary by genotype. Genotypes 1 and 2 are common in outbreaks in low- and middle-income regions, where contaminated water is the main vehicle of transmission. Genotypes 3 and 4 are found in many parts of the world and can cause sporadic cases in otherwise healthy adults as well as chronic infections in immunosuppressed individuals, such as solid organ transplant recipients. Pregnancy, particularly with genotype 1, is associated with higher mortality in some outbreaks.

Clinical features range from asymptomatic to acute hepatitis. The incubation period is about 2-10 weeks. Symptoms include fever, fatigue, nausea, abdominal pain, and jaundice, with elevated liver enzymes. Most infections resolve spontaneously within weeks. Chronic hepatitis E can occur in immunocompromised patients and may progress to cirrhosis if untreated.

Diagnosis relies on serology and molecular testing. Anti-HEV IgM indicates recent infection, while anti-HEV IgG indicates past exposure. HEV RNA can be detected by PCR in serum or stool. Differential diagnosis includes hepatitis A, B, C, and D.

Treatment is usually supportive. Chronic HEV infection may be treated with ribavirin in immunocompromised patients, and reducing immunosuppression when possible. Prevention focuses on safe water and sanitation, hygiene, and proper cooking of pork and other meats. A vaccine (HEV 239, Hecolin) is licensed in China but is not widely available elsewhere.

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