Hepatitis B

  • What is hepatitis B?

    Hepatitis B is a potentially life-threatening liver infection caused by the hepatitis B virus (HBV). Hepatitis B infection can be either acute or chronic. Acute hepatitis B infection is short-term, lasting a few weeks. Chronic hepatitis B infection is lifelong and can cause illnesses like cirrhosis and liver cancer.1,2

    Hepatitis B Infection Can Range From an Acute Illness Lasting a Few Weeks to a Chronic, Lifelong Illness Hepatitis B Infection Can Range From an Acute Illness Lasting a Few Weeks to a Chronic, Lifelong Illness
    Lasting a few weeks
    Lifelong illness
  • What is the prevalence of hepatitis B?

    An estimated 2 billion people worldwide have been infected with HBV, and more than 350 million people have chronic, lifelong HBV infections.3

    US Prevalence

    In the US, an estimated 850,000 to 2.2 million people are chronically infected with HBV. New cases of HBV infection in the US had been decreasing until recently. In 2013, there was a 5% increase in acute HBV infections over the previous year, marking the first time in over 20 years that cases had actually increased.4

  • What are the signs and symptoms of acute hepatitis B?

    Hepatitis B doesn't always cause symptoms. Infants, children, and approximately 50% of adults who have acute HBV infections are typically asymptomatic; however, they are still capable of infecting others.3

    For those who do experience symptoms, however, acute hepatitis B may be manifested as1,3:

    • Yellowing of the skin and eyes (jaundice)
    • Dark urine
    • Extreme fatigue
    • Nausea
    • Vomiting
    • Loss of appetite (anorexia)
    • Upper right quadrant abdominal discomfort
  • Who is at risk for chronic hepatitis B?

    The likelihood that infection becomes chronic depends upon the age at which a person becomes infected.2

    About 90%
    of infected infants
    develop chronic

    About 25–50%
    of infected
    children between
    1 and 5 years of age
    develop chronic

    About 5%
    of infected adults
    develop chronic

  • How serious is 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.3

    Chronic infection is responsible for most HBV-related morbidity and mortality, including:

    • Chronic hepatitis
    • Cirrhosis
    • Liver failure
    • Hepatocellular carcinoma (liver cancer)

    People with chronic hepatitis B infection are at 12 to 300 times higher risk of hepatocellular carcinoma than noncarriers. Approximately 25% of people with chronic hepatitis B infection die prematurely from cirrhosis or liver cancer.3

  • How is hepatitis B transmitted?

    Hepatitis B transmission occurs through infected blood, semen, or other bodily fluid. People can become infected from2:

    • Perinatal transmission, where an infected mother passes the infection to her baby during birth
    • Sex with an infected partner
    • Sharing needles, syringes, or drug-preparation equipment
    • Sharing items such as toothbrushes, razors, or medical equipment with an infected person
    • Direct contact with blood or open sores of an infected person
    • Exposure to blood from needlesticks or other sharp instruments of an infected person
  • How does hepatitis B transmission NOT occur?

    Unlikely modes of hepatitis B transmission include2,3:

    • Kissing, hugging, holding hands
    • Sharing meals, bowls, or utensils with someone who is infected
    • Tears
    • Sweat
    • Urine
    • Stool
    • Droplet nuclei (airborne transmission through coughing or sneezing, for example)
    • Breastfeeding
    • Food
    • Water
  • How is hepatitis B diagnosed?

    Diagnosis is based on clinical, laboratory, and epidemiologic findings. HBV infection cannot be differentiated on the basis of clinical symptoms alone, and definitive diagnosis depends on the results of serologic testing. Serologic markers of HBV infection vary depending on whether the infection is acute or chronic.3

  • How is hepatitis B treated?

    Acute Hepatitis B Treatment

    There is no specific treatment for acute hepatitis B. Instead, care is aimed at maintaining comfort and nutritional balance, including replacement of fluids lost from vomiting and diarrhea.1

    Chronic Hepatitis B Treatment

    Chronic hepatitis B infection can be treated with medicines to slow the progression of cirrhosis, reduce incidence of liver cancer, and improve long-term survival.1

    However, treatment does not cure hepatitis B in most people. It only suppresses viral replication. Therefore, most people who start treatment must continue it for life.1

Disease Information

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CDC Information

CDC=Centers for Disease Control and Prevention.

HBV=hepatitis B virus.

VACC-1258078-0000 11/18
1. World Health Organization (WHO). Hepatitis B fact sheet. Available at http://www.who.int/news-room/fact-sheets/detail/hepatitis-b. Accessed August 13, 2018.
2. Centers for Disease Control and Prevention (CDC). Hepatitis B questions and answers for the public. Available at https://www.cdc.gov/hepatitis/hbv/bfaq.htm. Accessed August 13, 2018.
3. 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 August 9, 2018.
4. US Department of Health & Human Services. Hepatitis B basic information. Available at https://www.hhs.gov/hepatitis/learn-about-viral-hepatitis/hepatitis-b-basics/index.html. Accessed August 13, 2018.
5. Centers for Disease Control and Prevention (CDC). Know hepatitis B. Available at https://www.cdc.gov/knowhepatitisb/. Accessed August 13, 2018.