HEV is a small nonenveloped virus that causes an acute, usually self-limited, infection that is spread by the fecal " “oral route. HEV is endemic in Southeast and Central Asia, with several outbreaks observed in the Middle East, northern and western parts of Africa, and Mexico. In developed countries, HEV infection occurs mainly in persons who have traveled to disease endemic areas.
Transmission of HEV may also occur parenterally. Direct person-to-person transmission is rare. Unusually high mortality (approximately 20%) occurs in patients infected in the third trimester of pregnancy. There is no carrier state associated with HEV.
Viremia and virus shedding occur in the preicteric phase and last up to 10 days into the clinical phase. After an incubation period ranging from 15 to 60 days, HEV-infected patients develop symptoms of hepatitis with appearance of anti-HEV IgM antibody in serum, followed by detectable anti-HEV IgG antibody within a few days. Anti-HEV IgM remains positive for up to 6 months after onset of symptoms, whereas anti-HEV IgG levels usually persist for years after infection. Anti-HEV IgG is the serologic marker of choice for diagnosis of past HEV infection.
Normal range: Negative.
Use
HEV antibody IgM: diagnosing acute or recent (<6 months) hepatitis E infection
HEV antibody IgG: diagnosis of past hepatitis E
Interpretation
Increased in previous or current hepatitis E infection