Hepatitis means inflammation
of the liver, and the most common cause is infection with one
of 5 viruses, called hepatitis A,B,C,D, and E. All of these
viruses can cause an acute disease with symptoms lasting several
weeks including yellowing of the skin and eyes (jaundice); dark
urine; extreme fatigue; nausea; vomiting and abdominal pain.
It can take several months to a year to feel fit again. Hepatitis
B virus can cause chronic infection in which the patient never
gets rid of the virus and many years later develops cirrhosis
of the liver or liver cancer. HBV is the most serious type of
viral hepatitis and the only type causing chronic hepatitis
for which a vaccine is available.
WAYS OF INFECTION
Hepatitis B virus is transmitted by contact with
blood or body fluids of an infected person in the same way as human
immunodeficiency virus (HIV), the virus that causes AIDS. However,
HBV is 45 to 100 times more infectious than HIV.
The main ways of getting infected with HBV are:
Worldwide, most infections occur from infected
mother to child, from child to child contact in household settings,
and from reuse of unsterilized needles and syringes. In many developing
countries, almost all children become infected with the virus.
In many industrialized countries (e.g. Western
Europe and North America), the pattern of transmission is different.
In these countries, mother-to-infant and child-to-child transmission
accounted for up to one third of chronic infections before childhood
hepatitis B vaccination programmes were implemented. However, the
majority of infections in these countries are acquired during young
adulthood by sexual activity, and injecting drug use. In addition,
hepatitis B virus is the major infectious occupational hazard of
health workers, and most health care workers have received hepatitis
Hepatitis B virus is not spread by contaminated
food or water, and cannot be spread casually in the workplace.