Description
Hepatitis A is a self-limited disease and chronic stage or
other complications are rare. Infections occur early in life in
areas with poor sanitation and crowded living conditions.
With improved sanitation and hygiene, infections are
delayed and consequently the number of persons
susceptible to the disease increases. Because the disease
is transmitted through the fecal-oral route, in dense
populated regions an outbreak can arise from single
contaminated source. The cause of hepatitis A is hepatitis
A virus (HAV)-non enveloped positive strand RNA virus
with a linear single strand genome, encoding for only one
known serotype. HAV has four major, structural
polypeptides and it localizes exclusively in the cytoplasm
of human hepatocites. The infection with HAV induces
strong immunological response and elevated levels first of
IgM and then IgG are detectable within a few days after
the onset of the symptoms. IgG is an indicator of past
infection and immunity to HAV.
