Diseases and vaccines

Hepatitis B

Hepatitis B disease

  • Hepatitis B virus (HBV) is a major cause of hepatitis B, an infection of the liver that can lead to death.
  • High endemicity is reported in Africa, Eastern Europe, South America, the eastern Mediterranean region, Southeast Asia and China, and the Pacific Islands (except for Australia, New Zealand, and Japan). As much as 15 percent of the population in most of these areas are chronically infected carriers of the hep B virus.
  • Infection in adults usually is self-limiting and often results in acute disease with jaundice (yellowing of the eyes and skin), dark urine, loss of appetite, and extreme fatigue lasting weeks or months.
  • Infected children rarely develop acute disease, but 25–90% become chronic carriers of the virus .
  • More than 2 billion people worldwide have been infected with HBV, and 360 million are chronic HBV carriers. Hepatitis B disease kills about 500,000 to 700,000 people each year.
  • HBV causes 60–80% of the world's primary liver cancer, the number one cause of cancer deaths in males in sub-Saharan Africa and much of Asia and a significant cause of cancer deaths in women.
  • Infants and young children are most at risk of HBV.
  • The virus is spread perinatally from an infected mother to her infant at birth, from child to child, from unsafe injections and transfusions, and through sexual contact. Although this is similar to the AIDS-causing virus, HIV, the hepatitis B virus is 40 to 100 times more infectious than HIV.

Hepatitis B vaccine

  • Available since 1982, the hepatitis B vaccine is the first vaccine against a major human cancer. The vaccine is produced from plasma or by recombinant DNA technology and is safe and effective. To date, more than 1 billion doses have been used.
  • Vaccination usually requires receiving 3 doses of vaccine; the first 2 doses are usually given one month apart, and the third dose is given 1 to 12 months later. Immunization schedules differ in different countries in accordance with national policies and the epidemiology of the disease—check with national health authorities for the current recommendation in your country. For the US schedule, visit our Parents and teens page.
  • To prevent perinatal (mother-to-child) transmission, a first dose of vaccine is given as soon as possible after birth, ideally within 24 hours.
  • To simplify immunization schedules, hepatitis B vaccine is often given at the same time as diphtheria-tetanus-pertussis (DTP) vaccine. However, DTP cannot be given at birth; hence, if a birth dose is given, it is usually monovalent hepatitis B vaccine.
  • When used as recommended, the vaccine is about 95% effective against hepatitis B disease.
  • Hepatitis B vaccine can be given concurrently with other vaccines such as measles, DTP, polio, BCG and yellow fever.
  • The World Health Organization (WHO) recommends that all countries add hepatitis B vaccine to their national immunization programs. According to WHO/UNICEF data, 160 member states (85%) have introduced hepatitis B vaccine into routine immunization schedules. As of 2006, 60 percent of 1-year-old children have been vaccinated against hepatitis B.
  • Initially, hepatitis B vaccines cost substantially more than traditional vaccines, and children in the poorest developing countries were not receiving it. New and innovative financing mechanisms were developed to cover the high cost and ensure sustainability of hepatitis B vaccine introduction, including a subsidy provided to the poorest 75 countries by the GAVI Alliance and procurement mechanisms such as the Pan American Health Organization Revolving Fund. As new hepatitis B vaccine manufacturers joined the market, competition drove prices down. In 1980, hepatitis B vaccine cost approximately US$100 per dose. In 2006, the UNICEF Supply Division list price was US$0.25.

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