Hepatitis B is a viral infection that causes liver inflammation and damage. Inflammation is swelling that occurs when tissues of the body become injured or infected. Inflammation can damage organs.
Viruses invade normal cells in your body. Many viruses cause infections that can spread from person to person. The hepatitis B virus spreads through contact with an infected person’s blood, semen, or other body fluids.
You can take steps to protect yourself from hepatitis B, including getting the hepatitis B vaccine. If you have hepatitis B, you can take steps to prevent spreading hepatitis B to others.
The hepatitis B virus can cause an acute or chronic infection.
Acute hepatitis B is a short-term infection. Some people have symptoms, which may last several weeks. In some cases, symptoms last up to 6 months. Sometimes the body is able to fight off the infection and the virus goes away. If the body isn’t able to fight off the virus, the virus does not go away, and chronic hepatitis B infection occurs.
Most healthy adults and children older than 5 years who have hepatitis B get better and do not develop a chronic hepatitis B infection. 6
Chronic hepatitis B is a long-lasting infection. Your chance of developing chronic hepatitis B is greater if you were infected with the virus as a young child. About 90 percent of infants infected with hepatitis B develop a chronic infection. About 25 to 50 percent of children infected between the ages of 1 and 5 years develop chronic infections. However, only about 5 percent of people first infected as adults develop chronic hepatitis B. 6
Hepatitis B infection is more common in some other parts of the world than it is in the United States. Though less than 0.5 percent of the U.S. population has hepatitis B, 2 percent or more of the population is infected in areas such as Africa, Asia, and parts of the Middle East, Eastern Europe, and South America. 7,8,9
Hepatitis B infection has been especially common in some parts of the world, such as sub-Saharan Africa and parts of Asia, where 8 percent or more of the population was infected. 9 In some of these areas, Hepatitis B infection rates are now lower than they were, but infection rates are still higher in these areas than in the United States. 8,9
In the United States, about 862,000 people have chronic hepatitis B. 6 Asian Americans and African Americans have higher rates of chronic hepatitis B than other U.S. racial and ethnic groups. 10 Researchers estimate that about half of the people living with chronic hepatitis B in the United States are Asian Americans and Pacific Islanders. 11 Chronic hepatitis B is also more common among people born in other countries than among those born in the United States. 7
The hepatitis B vaccine has been available since the 1980s and, in 1991, doctors began recommending that children in the United States receive the hepatitis B vaccine. The annual rate of acute hepatitis B infections went down 88.5 percent between 1982 and 2015. 12 In 2017, the annual number of hepatitis B infections rose in some states. 13 Experts think the rise was related to increases in injection drug use. Injection drug use increases the risk of hepatitis B infection.
People are more likely to get hepatitis B if they are born to a mother who has hepatitis B. The virus can spread from mother to child during birth. For this reason, people are more likely to have hepatitis B if they
People are also more likely to have hepatitis B if they
In the United States, hepatitis B spreads among adults mainly through contact with infected blood through the skin, such as during injection drug use, and through sexual contact. 12
Screening is testing for a disease in people who have no symptoms. Doctors use blood tests to screen for hepatitis B. Many people who have hepatitis B don’t have symptoms and don’t know they are infected with hepatitis B. Screening tests can help doctors diagnose and treat hepatitis B, which can lower your chances of developing serious health problems.
Your doctor may recommend screening for hepatitis B if you 9,14
Hepatitis B may lead to serious complications. Early diagnosis and treatment can lower your chances of getting complications.
In rare cases, acute hepatitis B can lead to acute liver failure, a condition in which the liver fails suddenly. People with acute liver failure may require a liver transplant.
Chronic hepatitis B can lead to
In people who have ever had hepatitis B, the virus may become active again, or reactivated, later in life. When hepatitis B is reactivated, it may start to damage the liver and cause symptoms. Reactivated hepatitis B can lead to acute liver failure.
People at risk for reactivated hepatitis B include those who
Doctors may test for current or past hepatitis B infection in people at risk for reactivated hepatitis B.
Many people infected with hepatitis B have no symptoms.
Some people with acute hepatitis B have symptoms 2 to 5 months after they come in contact with the virus. 6 These symptoms may include
Infants and children younger than age 5 typically don’t have symptoms of acute hepatitis B. Older children and adults are more likely to have symptoms. 6
If you have chronic hepatitis B, you may not have symptoms until complications develop, which could be decades after you were infected. For this reason, hepatitis B screening is important, even if you have no symptoms.
The hepatitis B virus causes hepatitis B. The hepatitis B virus spreads through contact with an infected person’s blood, semen, or other body fluids. Contact can occur by
You can’t get hepatitis B from
Mothers who have hepatitis B can safely breastfeed their babies. If a baby receives hepatitis B immune globulin (HBIG) and starts receiving the hepatitis B vaccine to prevent hepatitis B infection shortly after birth, hepatitis B is unlikely to spread from mother to child through breastfeeding. 15
Doctors diagnose hepatitis B based on your medical and family history, a physical exam, and blood tests. If you have hepatitis B, your doctor may perform additional tests to check your liver.
Your doctor will ask about your symptoms and about factors that may make you more likely to get hepatitis B. Your doctor may ask whether you have a family history of hepatitis B or liver cancer. Your doctor may also ask about other factors that could damage your liver, such as drinking alcohol.
During a physical exam, your doctor will check for signs of liver damage such as
Doctors use blood tests to diagnose hepatitis B. Your doctor may order additional tests to check for liver damage, find out how much liver damage you have, or rule out other causes of liver disease.
Your doctor may order one or more blood tests to diagnose hepatitis B. A health care professional will take a blood sample from you and send the sample to a lab.
Certain blood tests can show whether you are infected with hepatitis B. If you are infected, your doctor may use other blood tests to find out
If you have chronic hepatitis B, your doctor will recommend testing your blood regularly because chronic hepatitis B can change over time. Even if the infection is not damaging your liver when you are first diagnosed, it may damage your liver in the future. Your doctor will use regular blood tests to check for signs of liver damage, find out if you need treatment, or see how you are responding to treatment.
Blood tests can also show whether you are immune to hepatitis B, meaning you can’t get hepatitis B. You may be immune if you got a vaccine or if you had an acute hepatitis B infection in the past and your body fought off the infection.
If you’ve had chronic hepatitis B a long time, you could have liver damage. Your doctor may recommend additional tests to find out whether you have liver damage, how much liver damage you have, or to rule out other causes of liver disease. These tests may include
Doctors typically use liver biopsy only if other tests don’t provide enough information about a person’s liver damage or disease. Talk with your doctor about which tests are best for you.
Doctors typically don’t treat hepatitis B unless it becomes chronic. Doctors may treat chronic hepatitis B with antiviral medicines that attack the virus.
Not everyone with chronic hepatitis B needs treatment. If blood tests show that hepatitis B could be damaging a person’s liver, a doctor may prescribe antiviral medicines to lower the chances of liver damage and complications.
Medicines that you take by mouth include
A medicine that doctors can give as a shot is peginterferon alfa-2a (Pegasys).
The length of treatment varies. Hepatitis B medicines may cause side effects. Talk with your doctor about the side effects of treatment. Tell your doctor before taking any other prescription or over-the-counter medicines.
For safety reasons, you also should talk with your doctor before using dietary supplements, such as vitamins, or any complementary or alternative medicines or medical practices.
If chronic hepatitis B leads to cirrhosis, you should see a doctor who specializes in liver diseases. Doctors can treat the health problems related to cirrhosis with medicines, minor medical procedures, and surgery. If you have cirrhosis, you have an increased chance of liver cancer. Your doctor may order blood tests and an ultrasound or another type of imaging test to check for liver cancer.
If chronic hepatitis B leads to liver failure or liver cancer, you may need a liver transplant.
You can protect yourself from hepatitis B by getting the hepatitis B vaccine. If you have not had the vaccine, you can take steps to reduce your chance of infection.
The hepatitis B vaccine has been available since the 1980s and should be given to newborns, children, and teens in the United States. Adults who are more likely to be infected with hepatitis B or who have chronic liver disease should also get the vaccine. The hepatitis B vaccine is safe for pregnant women.
Doctors most often give the hepatitis B vaccine in three shots over 6 months. You must get all three shots to be fully protected. In some cases, doctors may recommend a different number or timing of vaccine shots.
If you are traveling to countries where hepatitis B is common and you haven’t received the hepatitis B vaccine, talk with your doctor and try to get all the shots before you go. If you don’t have time to get all the shots before you travel, get as many as you can. Even one shot may give you some protection against the virus.
You can reduce your chance of hepatitis B infection by
If you think you have been in contact with the hepatitis B virus, see your doctor right away. Doctors typically recommend a dose of the hepatitis B vaccine to prevent infection. In some cases, doctors may also recommend a medicine called hepatitis B immune globulin (HBIG) to help prevent infection. You must get the vaccine dose and, if needed, HBIG shortly after coming into contact with the virus, preferably within 24 hours.
If you have hepatitis B, follow the steps above to avoid spreading the infection. Your sex partners should get a hepatitis B test and, if they aren’t infected, get the hepatitis B vaccine. You can protect others from getting infected by telling your doctor, dentist, and other health care professionals that you have hepatitis B. Don’t donate blood or blood products, semen, organs, or tissue.
If you are pregnant and have hepatitis B, talk with your doctor about lowering the risk that the infection will spread to your baby. Your doctor will check your virus levels during pregnancy. If virus levels are high, your doctor may recommend treatment during pregnancy to lower virus levels and reduce the chance that hepatitis B will spread to your baby. Your doctor may refer you to a liver specialist to find out if you need hepatitis B treatment and to check for liver damage.
When it is time to give birth, tell the doctor and staff who deliver your baby that you have hepatitis B. A health care professional should give your baby the hepatitis B vaccine and HBIG right after birth. The vaccine and HBIG will greatly reduce the chance of your baby getting the infection.
If you have hepatitis B, you should eat a balanced, healthy diet. Obesity can increase the chance of nonalcoholic fatty liver disease (NAFLD), and NAFLD can increase liver damage in people who have hepatitis B. Talk with your doctor about healthy eating and maintaining a healthy weight.
You should also avoid alcohol because it can cause more liver damage.
The NIDDK conducts and supports clinical trials in many diseases and conditions, including liver diseases. The trials look to find new ways to prevent, detect, or treat disease and improve quality of life.
Clinical trials—and other types of clinical studies—are part of medical research and involve people like you. When you volunteer to take part in a clinical study, you help doctors and researchers learn more about disease and improve health care for people in the future.
Researchers are studying many aspects of hepatitis B, such as
You can view a filtered list of clinical studies on hepatitis B that are federally funded, open, and recruiting at www.ClinicalTrials.gov. You can expand or narrow the list to include clinical studies from industry, universities, and individuals; however, the NIH does not review these studies and cannot ensure they are safe. Always talk with your health care provider before you participate in a clinical study.
The NIDDK and the NIH have supported many research projects to learn more about hepatitis B, including the NIDDK’s Hepatitis B Research Network (HBRN). The HBRN, a network of 28 clinical sites throughout the United States and Canada, studies how hepatitis B affects children and adults and explores new approaches to diagnosis and treatment.
[6] Hepatitis B questions and answers for health professionals. Centers for Disease Control and Prevention. Reviewed October 23, 2019. Accessed October 24, 2019. www.cdc.gov/hepatitis/hbv/hbvfaq.htm.
[7] Patel EU, Thio CL, Boon D, Thomas DL, Tobian AAR. Prevalence of hepatitis B and hepatitis D virus infections in the United States, 2011–2016. Clinical Infectious Diseases. 2019. [Epub ahead of print] doi: 10.1093/cid/ciz001
[8] Centers for Disease Control and Prevention. Chapter 4: Travel-related infectious diseases. In: Centers for Disease Control and Prevention. CDC Yellow Book 2020: Health Information for International Travel. Oxford University Press; 2017. Accessed October 24, 2019. wwwnc.cdc.gov/travel/yellowbook/2020/travel-related-infectious-diseases/hepatitis-b
[9] U.S. Preventive Services Task Force. Screening for hepatitis b virus infection in nonpregnant adolescents and adults: U.S. Preventive Services Task Force recommendation statement. Annals of Internal Medicine. 2014;161(1):58–66. doi: 10.7326/M14-1018
[10] Kim HS, Rotundo L, Yang JD, et al. Racial/ethnic disparities in the prevalence and awareness of Hepatitis B virus infection and immunity in the United States. Journal of Viral Hepatitis. 2017;24(11):1052–1066. doi: 10.1111/jvh.12735
[11] Asian Americans and Pacific Islanders and Chronic Hepatitis B. Centers for Disease Control and Prevention, Division of Viral Hepatitis, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB prevention. Reviewed August 27, 2019. Accessed November 1, 2019. www.cdc.gov/hepatitis/populations/api.htm
[12] Schillie S, Vellozzi C, Reingold A, et al. Prevention of hepatitis B virus infection in the United States: recommendations of the Advisory Committee on Immunization Practices. MMWR Recommendation Report. 2018;67(1):1–31. doi: 10.15585/mmwr.rr6701a1
[13] Surveillance for Viral Hepatitis – United States, 2017. Centers for Disease Control and Prevention, Division of Viral Hepatitis. Reviewed September 10, 2019. Accessed September 11, 2019. www.cdc.gov/hepatitis/statistics/2017surveillance/index.htm
[14] U.S. Preventive Services Task Force. Screening for hepatitis B virus infection in pregnant women: U.S. Preventive Services Task Force reaffirmation recommendation statement. JAMA. 2019;322(4):349–354. doi: 10.1001/jama.2019.9365
[15] Hepatitis B and C infections. Centers for Disease Control and Prevention, Division of Nutrition, Physical Activity, and Obesity. Reviewed January 24, 2018. Accessed October 29, 2019. www.cdc.gov/breastfeeding/breastfeeding-special-circumstances/maternal-or-infant-illnesses/hepatitis.html
Last Reviewed June 2020 Share this page Print Facebook X Email More Options WhatsApp LinkedIn Reddit Pinterest Copy Link Previous: Hepatitis A Next: Hepatitis CThis content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health. NIDDK translates and disseminates research findings to increase knowledge and understanding about health and disease among patients, health professionals, and the public. Content produced by NIDDK is carefully reviewed by NIDDK scientists and other experts.
The NIDDK would like to thank:
Anna Suk-Fong Lok, M.D., University of Michigan
