Hepatitis E

HEPATITIS E

Hepatitis E is the cause of another form of hepatitis that is spread by the fecal–oral route and therefore resembles hepatitis A. Hepatitis E virus is an RNA virus that is similar to but distinct from caliciviruses. The viral particles in stool are spherical, 27 to 34 nm in size, and unenveloped and exhibit spikes on their surface. Like hepatitis A, infection with this virus is frequently subclinical. When symptomatic, it causes only acute disease that may fulminate, especially in pregnant women. In endemic, developing areas, it has the highest attack rate in young adults, and infection is usually associated with contaminated drinking water. It does not appear to spread from person to person. Most cases have been identified in developing countries with poor sanitation (eg, in Asia, Africa, and the Indian subcontinent), and recurrent epidemics have been described in these areas. Rarely have cases been identified in the United States, and these have been in visitors or immigrants from endemic areas. The incubation period is approximately 40 days. The diagnosis may be confirmed by demonstrating the presence of specific IgM antibody. It is likely but un-proven that ISG provides protection; no treatment is available. Liver transplant may be the only recourse in seriously ill patients.