Updated: Marzo 3, 2008
Most hepatitis B virus (HBV) infections occur in adolescents and adults but the consequences of infection in early childhood have long lasting and serious consequences, including liver cancer, chronic liver disease and death. Although hepatitis B is often thought of as a disease that affects people who are sexually active or who use intravenous drugs, in fact nearly one out of three patients who contract this disease have no known source of infection.
HBV causes an acute (short duration) infection in some and a long-lasting (or, chronic) infection in others.
The consequences of acute HBV infection can be serious. However some of the most serious outcomes from HBV infection occur many years or decades later in those who are chronically infected. For example, about 25% of infants and young children with chronic infection will die prematurely as adolescents or, more typically, as adults from liver disease or liver cancer.1
For these reasons, prevention of HBV transmission from person to person early in life is important.
HBV causes 5,000 deaths each year in the United States, including 3,000–4,000 from cirrhosis and approximately 1,000–1,500 from primary liver cancer.
The estimated medical and work loss cost per year of HBV is $700 million in the U.S.2 About 1.25 million people in the US have chronic HBV infection; worldwide, more than 350 million people have chronic HBV infection.
The current hepatitis B vaccine has been used in the United States since 1986. Initially the vaccine was recommended only for people who were identified to be at a high risk for acquiring the infection. In 1991, the recommendation was extended to include all infants as well. In 1995 and 1999, the universal hepatitis B vaccine recommendations were extended to all children less than 18 years of age. In 2005, a comprehensive strategy to eliminate HBV transmission in the US was published1 that includes newborn immunization beginning at birth and aggressively identifying infected mothers and treating their newborns.
Hepatitis B vaccine is protective against both acute and chronic HBV infections, reducing the risks of all HBV complications, including liver cancer.1 Even if antibody wanes over time the vaccinated person appears to continue to be protected. Usually 3 doses of vaccine are required to provide protection.
Between 1990 and 2002, acute hepatitis B declined from 21,102 cases reported to 8,064.3 The incidence of acute hepatitis B among children and adolescents declined 89%4 and the prevalence of chronic HBV infection was also reduced.5
After a decade, a program?that was begun in 1992 in British Columbia targeting hepatitis b immunization of 11 year old children?reduced HBV transmission, eliminating HBV infection in adolescents.6.
Hepatitis B vaccine has proven to be extremely safe, including when given to newborns, children, and adolescents.4 5 7 Local temporary pain at the injection site occurs in about ofne third of vaccines and low grade fever can occur as well. A very small number of people should not receive the hepatitis B vaccine, such as those who have had a life-threatening allergy to baker’s yeast or a previous dose of the vaccine.
Some parents resist hepatitis B immunization for their children because of vaccine safety concerns or uncertaintly about their child’s risk of exposure to the HBV.8
Hypotheses that a number of chronic illnesses might be caused by Hepatitis B vaccine have not been able to be substantiated. For example, the Institute of Medicine Vaccine Safety Review Committee concluded that the data favored rejection of an association between multiple sclerosis and hepatitis B vaccine administration; there was insufficient data, however, to exclude an association with other demyelinating diseases.9
Some parents regard hepatitis B immunization as unnecessary, based on the misconception that this is a disease for which their children are not at risk. These parents think that hepatitis B is a disease mainly of intravenous drug users, sex workers, men who have sex with men, healthcare workers (largely because of accidental needle stick exposure) and prison inmates.
While HBV is most effectively transmitted from one person to another through blood and body fluids by sexual contact, injection drug use, or occupational exposure,
For these reasons, HBV vaccine is recommended for everyone 18 years and younger, starting with the first dose shortly after birth (prior to discharge from the newborn nursery).1 Of course, anyone with risk factors should also be immunized no matter what their age.1