Hepatitis E virus (HEV)

• Virus that causes an acute hepatitis that self resolves
• Majority of infections are asymptomatic.
• Previously thought to only be acquired overseas, however 8-10% of NZ blood donors have serological evidence of infection.
• Can cause chronic infection in people with significant immunosuppression (e.g. liver transplantation)

• Hepatitis E is transmitted by the faecal-oral route.
• Genotypes 1 and 2 cause infection in humans only and are endemic in Asia and Africa
• Genotypes 3 and 4 are zoonotic and are present in Europe, USA and Asia. Infection is usually transmitted by consumption of undercooked meat such as pork. 90% of NZ pigs show serological evidence of infection.

Testing generally reserved for patients with acute hepatitis (ALT > 500) with history of travel to endemic regions or with no alternative diagnosis.

• Mimics to consider in patients with hepatitis: hepatitis A, B and C, HIV, syphilis
• In an outbreak setting a lower threshold for testing is usually warranted

Request Hep E serology

Hepatitis E virus serology – IgM and IgG

• Anti-HEV IgM is usually detectable 2-3 weeks after exposure and is usually negative after 3-6 months. Therefore detection is consistent with acute infection.
• Anti-HEV IgG is detectable early in the illness and is long lasting. Detection is usually consistent with prior infection if the IgM is negative.

Hepatitis E virus PCR

• Used to diagnose chronic HEV infection in immunosuppressed patients