HBV infection is an established cause of acute and chronic hepatitis and cirrhosis. An estimated 2 billion persons worldwide have been infected with HBV, and more than 350 million persons have chronic, lifelong infections. It is the cause of up to 50% of hepatocellular carcinomas.1
- What is hepatitis B?
- What are the clinical features of acute hepatitis B?
The incubation period ranges from 45 to 160 days, with an average of 120 days. Infants, children (aged <10 years), and approximately 50% of adults who have acute infections are typically asymptomatic.
Acute hepatitis B manifests itself as a nonspecific prodrome with malaise, anorexia, nausea, vomiting, and upper right quadrant abdominal discomfort. Physical signs include jaundice and an enlarged liver.1
- How is hepatitis B transmitted?
For infants and children, the 2 primary sources of hepatitis B infection are perinatal transmission from infected mothers and horizontal transmission from infected household contacts.2
Adolescents are at risk for HBV infection primarily through high-risk sexual activity (ie, sex with more than one partner and male sexual activity with other males) and injection-drug use.2
Persons with chronic infection are often asymptomatic and may not be aware that they are infected; however, they are capable of infecting others and have been referred to as carriers.1
- What are the complications of hepatitis B?
Although the consequences of acute HBV infection can be severe, most of the serious complications associated with HBV infection are due to chronic infection.1
Chronic infection is responsible for most HBV-related morbidity and mortality, including chronic hepatitis, cirrhosis, liver failure, and hepatocellular carcinoma. Approximately 25% of persons with chronic HBV infection die prematurely from cirrhosis or liver
Persons with chronic HBV infection are at 12 to 300 times higher risk of hepatocellular carcinoma than noncarriers. Each year in the United States, an estimated 1,000 to 1,500 persons die of hepatitis B-related liver cancer.1
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CDC=Centers for Disease Control and Prevention.
HBV=hepatitis B virus.
|1.||Centers for Disease Control and Prevention (CDC). Hepatitis B. In: Hamborsky J, Kroger A, Wolfe S, eds. Epidemiology and Prevention of Vaccine-Preventable Diseases. 13th ed. Washington, DC: Public Health Foundation; 2015:149–174. http://www.cdc.gov/vaccines/pubs/pinkbook/index.html. Accessed October 27, 2016.|
|2.||Centers for Disease Control and Prevention (CDC). A comprehensive immunization strategy to eliminate transmission of hepatitis B virus infection in the United States: recommendations of the Advisory Committee on Immunization Practices (ACIP): Part 1: Immunization of infants, children, and adolescents. MMWR Recomm Rep.