Key facts:

Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease.

The virus is transmitted through contact with the blood or other body fluids of an infected person - not through casual contact.

About 2 billion people worldwide have been infected with the virus and about 350 million live with chronic infection. An estimated 600 000 persons die each year due to the acute or chronic consequences of hepatitis B.

About 25% of adults who become chronically infected during childhood later die from liver cancer or cirrhosis (scarring of the liver) caused by the chronic infection.

The hepatitis B virus is 50 to 100 times more infectious than HIV.

Hepatitis B virus is an important occupational hazard for health workers.