Hepatitis B
A viral liver infection that can be short-term or become chronic, leading to cirrhosis, liver failure, or liver cancer.
What causes Hepatitis B?
Hepatitis B is caused by the hepatitis B virus. It spreads through infected blood, semen, and certain other body fluids, including during birth, sex, sharing injection equipment, or unsafe needle and medical exposures.
Symptoms and what to notice
Many infections are silent. Acute symptoms can include fatigue, fever, loss of appetite, nausea, abdominal pain, dark urine, pale stools, joint pain, and jaundice. Chronic infection may remain unnoticed until liver damage is advanced.
How long can it last?
Acute symptoms can begin about 60 to 150 days after exposure and last several weeks to months. Infection becomes chronic when the virus persists beyond six months. Chronic hepatitis B may last for life without treatment or immune clearance.
How serious is Hepatitis B?
Chronic hepatitis B can cause cirrhosis, liver failure, and hepatocellular carcinoma. Risk of chronic infection is highest after birth and early childhood infection and much lower after adult infection.
Treatment and management
Most acute infections receive supportive care. Chronic hepatitis B requires specialist monitoring; effective antivirals such as tenofovir or entecavir can suppress the virus and reduce liver damage, but many patients need long-term treatment. Severe acute liver failure needs urgent hospital care.
Vaccine: who and when?
Single-antigen U.S. products are Engerix-B, Recombivax HB, and Heplisav-B. Combination products include Pediarix, Vaxelis, and Twinrix. Infants should receive a birth dose and complete the series. CDC recommends vaccination for all unvaccinated adults ages 19-59 and risk-based or requested vaccination for adults 60 and older. Heplisav-B is a two-dose adult series; product schedules otherwise vary.
Cost note: Cost varies by product, schedule, provider, insurance, and eligibility. The birth dose and routine childhood series are commonly covered, and eligible children can receive vaccine through the Vaccines for Children program.
Trusted source
Patient cost varies by insurance, provider, location, and eligibility. Coverage and public-health access differ, so listed prices are examples rather than guaranteed patient prices. This page is for general education and does not replace individualized medical advice, diagnosis, vaccination assessment, or treatment.
Hepatitis B: Symptoms, Causes, Treatment, Prevention, and Vaccine Information
Hepatitis B virus can cause a brief acute illness or persist as chronic infection. Because chronic infection may remain silent for decades, people can transmit the virus and develop progressive liver injury without realizing it. Universal infant vaccination, broader adult vaccination, prenatal screening, postexposure protection, and one-time adult screening are central to elimination efforts. Effective treatment suppresses chronic infection, but prevention remains preferable because current medicines do not reliably eradicate all viral material from liver cells.
Important: This page is for general education. It does not replace diagnosis, treatment, vaccination advice, or emergency care from a qualified healthcare professional.
Quick Facts
| Topic | Current information |
|---|---|
| Cause | Hepatitis B is caused by the hepatitis B virus. It spreads through infected blood, semen, and certain other body fluids, including during birth, sex, sharing injection equipment, or unsafe needle and medical exposures. |
| Main symptoms | Many infections are silent. Acute symptoms can include fatigue, fever, loss of appetite, nausea, abdominal pain, dark urine, pale stools, joint pain, and jaundice. Chronic infection may remain unnoticed until liver damage is advanced. |
| Typical course | Acute symptoms can begin about 60 to 150 days after exposure and last several weeks to months. Infection becomes chronic when the virus persists beyond six months. Chronic hepatitis B may last for life without treatment or immune clearance. |
| Treatment | Most acute infections receive supportive care. Chronic hepatitis B requires specialist monitoring; effective antivirals such as tenofovir or entecavir can suppress the virus and reduce liver damage, but many patients need long-term treatment. Severe acute liver failure needs urgent hospital care. |
| Vaccine status | Single-antigen U.S. products are Engerix-B, Recombivax HB, and Heplisav-B. Combination products include Pediarix, Vaxelis, and Twinrix. Infants should receive a birth dose and complete the series. CDC recommends vaccination for all unvaccinated adults ages 19-59 and risk-based or requested vaccination for adults 60 and older. Heplisav-B is a two-dose adult series; product schedules otherwise vary. |
History and Public-Health Importance
The discovery of hepatitis B surface antigen led to blood screening and the first hepatitis B vaccines. Modern vaccines use recombinant surface antigen rather than human plasma. Universal infant vaccination and routine screening of donated blood dramatically reduced transmission in the United States. The remaining burden is concentrated among people infected at birth in higher-prevalence regions, unvaccinated adults with blood or sexual exposure, and people who lack access to testing and care.
What Causes Hepatitis B?
Hepatitis B is caused by the hepatitis B virus. It spreads through infected blood, semen, and certain other body fluids, including during birth, sex, sharing injection equipment, or unsafe needle and medical exposures.
HBV enters through blood or sexual fluids. Important routes include birth from an infected mother, sex, shared injection equipment, needlestick exposure, tattooing or piercing with unsterile equipment, and shared blood-contaminated items such as razors. It does not spread through coughing, hugging, food, water, breastfeeding, or ordinary casual contact. The virus can survive on surfaces for at least seven days, so proper disinfection and standard precautions matter.
Symptoms and Typical Course
Many infections are silent. Acute symptoms can include fatigue, fever, loss of appetite, nausea, abdominal pain, dark urine, pale stools, joint pain, and jaundice. Chronic infection may remain unnoticed until liver damage is advanced.
Most young children and many adults have no acute symptoms. When symptoms occur, they may include fatigue, nausea, abdominal pain, dark urine, pale stools, and jaundice. Adults usually clear acute infection, while about 90% of infants infected at birth develop chronic infection. Chronic disease can alternate between active and inactive phases, requiring repeated laboratory and imaging assessment.
Complications and Who Is at Higher Risk
Chronic hepatitis B can cause cirrhosis, liver failure, and hepatocellular carcinoma. Risk of chronic infection is highest after birth and early childhood infection and much lower after adult infection.
Fulminant hepatitis can cause acute liver failure. Chronic infection may produce fibrosis, cirrhosis, portal hypertension, liver failure, and liver cancer, sometimes even without established cirrhosis. Coinfection with hepatitis D, hepatitis C, or HIV can worsen outcomes. Immunosuppressive cancer or rheumatologic therapy can reactivate previously controlled HBV, so screening before treatment is important.
How It Is Diagnosed
CDC recommends a triple-panel blood screen—HBsAg, anti-HBs, and total anti-HBc—for adults at least once and testing during every pregnancy. Results distinguish current infection, immunity from vaccination, immunity after past infection, and susceptibility. People with current infection need additional HBV DNA, liver enzyme, and fibrosis evaluation. Household and sexual contacts should be tested and vaccinated if susceptible.
Treatment and Recovery
Most acute infections receive supportive care. Chronic hepatitis B requires specialist monitoring; effective antivirals such as tenofovir or entecavir can suppress the virus and reduce liver damage, but many patients need long-term treatment. Severe acute liver failure needs urgent hospital care.
Acute hepatitis B is usually managed with hydration, nutrition, symptom care, and monitoring. Chronic treatment decisions depend on viral load, liver enzymes, fibrosis, age, pregnancy, coinfections, and cancer risk. Tenofovir disoproxil fumarate, tenofovir alafenamide, and entecavir are potent oral medicines with a high barrier to resistance. Treatment reduces but does not eliminate cancer risk, so surveillance may continue.
Vaccine Information
Single-antigen U.S. products are Engerix-B, Recombivax HB, and Heplisav-B. Combination products include Pediarix, Vaxelis, and Twinrix. Infants should receive a birth dose and complete the series. CDC recommends vaccination for all unvaccinated adults ages 19-59 and risk-based or requested vaccination for adults 60 and older. Heplisav-B is a two-dose adult series; product schedules otherwise vary.
Engerix-B and Recombivax HB are used from birth through adulthood in age-specific doses. Heplisav-B is a two-dose series for adults 18 and older. Pediarix and Vaxelis combine hepatitis B with pediatric vaccines; Twinrix combines hepatitis A and B for adults. All infants should receive vaccine soon after birth. Babies born to HBsAg-positive mothers need vaccine plus hepatitis B immune globulin within 12 hours and later postvaccination testing. PreHevbrio is no longer available after its manufacturer discontinued operations.
Prevention
Vaccinate, use condoms, never share injection equipment or blood-contaminated personal items, use licensed tattoo and piercing facilities, and follow occupational safety procedures. Pregnant people should be screened every pregnancy. After a significant exposure, prompt vaccine and sometimes hepatitis B immune globulin can prevent infection.
When to Seek Medical Care
Seek care for jaundice, confusion, severe vomiting, abdominal swelling, bleeding, or a known blood or sexual exposure. Pregnant people with hepatitis B need coordinated prenatal, delivery, and infant follow-up. People beginning immunosuppressive therapy should ask whether HBV screening is required.
Frequently Asked Questions
Can hepatitis B be cured?
Acute infection often clears naturally. Current chronic treatments suppress the virus very effectively but do not reliably eliminate it, so long-term monitoring is needed.
Can hepatitis B spread through food or hugging?
No. It spreads through infected blood and certain body fluids, not ordinary social contact, coughing, food, or water.
Which adult vaccine takes two doses?
Heplisav-B is given as two adult doses at least four weeks apart. Other product schedules differ.
Why is the birth dose important?
Infection acquired at birth has a very high chance of becoming chronic. Prompt vaccination blocks transmission before it can establish infection.
Key Takeaway
Hepatitis B can be silent for years but is preventable by vaccination and controllable with testing and antiviral care. The birth dose, pregnancy screening, and adult catch-up vaccination protect both individuals and future generations.
Medical, treatment, and vaccine information was reviewed against official U.S. public-health guidance available through September 2026.