Universal Hepatitis B Immunization

In the United States 200 000 to 300 000 acute infections with hepatitis B virus (HBV) occur each year.1’2 More than one million persons in the United States have chronic HBV infection, and approximately 4000 to 5000 persons die each year from HBV-induced chronic liver disease and hepatocellular carcinoma. Although HBV infections occur during childhood and adolescence, the full impact of these infections is not recognized until many years later when chronic liver disease and hepatocellular carcinoma may develop. The incidence of HBV infection increases rapidly during adolescence, with higher rates among blacks than among whites (Fig 1). Although rates vary by region, sex, and race, between 3.3% and 25% of all persons have had HBV infection by 25 to 34 years of age. The likelihood of becoming chromcally infected with HBV varies inversely with the age at which infection occurs. HBV transmitted from hepatitis B surface antigen (HBsAg)-positive mothers to their newborns results in HBV carriage for up to 90% of infants. Between 25% and 50% of children infected before 5 years of age become carriers, whereas only 6% to 10% of acutely infected adults become carriers. It is estimated that more than 25% of carrier infants will die from primary hepatocellular carcinoma or cirrhosis of the liver, with most of these deaths occuring during adult life. HBV infection occurs more commonly in certain populations, including Pacific Islanders, Alaskan Natives, immigrants from countries in which infection is highly endemic, persons who require multiple transfusions of blood or blood products, and persons with high-risk lifestyles, including intravenous drug abuse and contact with multiple sexual partners. However, approximately 30% to 40% of acute HBV infections in the United States occur in persons with no identifiable risk factors. HBV is transmitted through exposure to blood and blood products, through sexual contact, and from mothers to infants primarily at the time of birth. It also can be acquired by close contact within families, from person to person through contact between open skin lesions, and possibly by exposure of mucous membranes to other infected body fluids, such as saliva.