The short answer
Chronic Hepatitis B infection is a leading cause of liver cancer worldwide. Vaccination provides safe, highly effective protection against infection and later liver damage.
Chronic hepatitis B infection is a leading cause of liver cancer worldwide.
Vaccination is safe and, WHO says, protects for at least 20 years and probably for life.
The harm builds over decades through persistent inflammation, cirrhosis and mutations in liver cells.
Ask whether you have been screened or vaccinated for hepatitis B, and screened for hepatitis C.
Watch: The other anti-cancer vaccine
45 sec · Captioned · The hepatitis B vaccine protects against a leading cause of liver cancer.
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The full explanation.
Chronic hepatitis B infection is a leading cause of liver cancer worldwide. The vaccine is safe and effective. WHO says it gives nearly 100% protection against the virus.
Representative Story Disclosure
This is a representative story created from common experiences described by patients and caregivers. It is not the story of one identifiable person, and individual experiences can differ substantially.
How hepatitis B leads to liver cancer
Hepatitis B is an infection of the liver caused by the hepatitis B virus. The infection can be short and severe, or it can become chronic, meaning it lasts a long time.
Chronic infection is the problem. It keeps the liver inflamed for years. Over time that can lead to cirrhosis, which is severe scarring of the liver, and to liver cancer. WHO estimates that hepatitis B caused about 1.1 million deaths in 2024, mostly from cirrhosis and liver cancer. NCI notes that chronic hepatitis B infection is the leading cause of liver cancer in Asia and Africa.
How the virus spreads
The virus travels in blood and other body fluids, such as semen and vaginal fluids. It can spread through sexual contact and through sharing needles used to inject drugs. It can also pass from a mother to her baby around the time of birth.
What the vaccine does
The hepatitis B vaccine is safe and effective. WHO says it gives nearly 100% protection against the virus.
- Timing. Babies should get the first dose as soon as possible after birth, ideally within 24 hours. Two or three more doses follow, at least four weeks apart.
- How long it lasts. Protection lasts at least 20 years and probably for life. People who finish the three-dose series do not usually need a booster.
- What it has changed. By 2019, fewer than 1% of children under 5 had chronic hepatitis B. Before vaccination programs began, the figure was around 5%.
Adults who were not vaccinated as children can still be vaccinated. Ask your care team whether the vaccine is right for you.
If you already have hepatitis B
A vaccine cannot treat an infection you already have. But chronic hepatitis B can be treated with antiviral medicines such as tenofovir or entecavir. WHO reports that treatment can slow the advance of cirrhosis, reduce cases of liver cancer, and improve long-term survival. Most people who start treatment stay on it for life.
This is why testing matters. Many people carry the virus for years without feeling ill. Ask your care team whether you have been tested.
Frequently Asked Questions
How does Hepatitis B cause liver cancer?
Long-term infection keeps the liver inflamed. Over decades that causes cirrhosis, or scarring, and changes in liver cells that can lead to cancer.
Questions to Ask Your Care Team
- "Have I been screened or vaccinated for Hepatitis B and Hepatitis C?"
- "What liver function or screening tests are appropriate for me?"
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Common questions
How does Hepatitis B cause liver cancer?
Chronic infection causes persistent liver inflammation, cirrhosis, and liver tissue cell mutations over decades.
Questions to ask your doctor
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Written by: Cancer ExplainedSources last checked: 2026-08-11 what this meansLast updated: 2026-08-18Next planned review: 2027-07-23
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How this page was created
Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and checked line by line against the sources listed on it. That confirms the sources support what the page says. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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