Non-enveloped, spherical, 32-34 nm in diameter. RNA genome is enclosed within a capsid
composed of 60 capsid proteins, assembled into T=1 isometric icosahedral particle.
Hepatitis E Virus
Monopartite, linear, ssRNA(+) genome . The 5’ end is capped and the 3’ terminus is
ORF1 encodes nonstructural proteins; ORF2 encodes capsid protein; ORF3 encodes small
By Oral,Fecal route. Zoonotic & Fomite.
Host : Human, pig, monkey,
some rodents,& chicken.
Primary site :
Secondary site :
possibly cells in
Treatment options for chronic hepatitis include:
The first step in the treatment is reduction of immuno supression medication in 16 solid organ transplant
recipients with chronic hepatitis E ,led to clearance of HEV in 4 cases (25%) .
A second possible treatment option is administration of pegylated -interferon α with ribavirin.
Treatment durations varied between 3 and 12 months.
Ribavirin has also been used in a not -transplanted patient with severe acute hepatitis E who showed rapid
improvement of symptoms and liver function tests during treatment .
No commercial HEV vaccine is currently available. A
vaccine developed by GSK & the Walter Reed Army
Institute that was successfully tested in a Phase II study
(Shrestha 2007). However, this vaccine has not been
A group from China reported data recently from a very large successful Phase III vaccine trial (Zhu 2010) . This trial
included almost 110,000 individuals who received either a recombinant HEV vaccine (“HEV 239”) or placebo. The
vaccine efficacy after 3 doses was 100%. Moreover, the efficacy of this vaccine needs to be evaluated in special risks
groups such as patients with end-stage liver disease or immuno suppressed individuals. It is also unknown if HEV -239
also protects from HEV genotype 3 infection (Wedemeyer and Pischke 2011)