title: Hepatitis B.
abstract: Hepatitis B causes significant morbidity and mortality worldwide. More than 400 million persons, including 1.25 million Americans, have chronic hepatitis B. In the United States, chronic hepatitis B virus infection is responsible for about 5,000 annual deaths from cirrhosis and hepatocellular carcinoma. Hepatitis B virus is found in body fluids and secretions; in developed countries, the virus is most commonly transmitted sexually or via intravenous drug use. Occupational exposure and perinatal transmission do occur but are rare in the United States. Effective vaccines for hepatitis B virus have been available since 1982; infant and childhood vaccination programs introduced in the 1990s have resulted in a marked decrease in new infections. Risk factors for progression to chronic infection include age at the time of infection and impaired immunity. From 15 to 30 percent of patients with acute hepatitis B infection progress to chronic infection. Medical therapies for chronic hepatitis B include interferon alfa-2b, lamivudine, and the nucleotide analog adefovir dipivoxil.
authors.affiliation: Department of Family and Community Medicine, Lancaster General Hospital, Lancaster, Pennsylvania 17604, USA.
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Lin
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Kirchner
mesh_terms: D000208:Acute Disease; D000998:Antiviral Agents / Q000627:therapeutic use; D006528:Carcinoma, Hepatocellular / Q000821:virology; D002908:Chronic Disease; D018450:Disease Progression; D006509:Hepatitis B / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy / Q000635:transmission; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000627:therapeutic use; D019259:Lamivudine / Q000627:therapeutic use; D008103:Liver Cirrhosis / Q000821:virology; D008113:Liver Neoplasms / Q000821:virology; D008403:Mass Screening; D018579:Patient Selection; D011994:Recombinant Proteins; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use; D012307:Risk Factors; D012749:Sexually Transmitted Diseases / Q000150:complications; D015819:Substance Abuse, Intravenous / Q000150:complications; D014481:United States / Q000453:epidemiology; D014611:Vaccination
chemical_list: D000998:Antiviral Agents; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine