AI Summary About 350 million people worldwide and more than 1.2 million people in the U.S. have hepatitis B, and chronic infection raises the risk of cirrhosis, liver failure, or liver cancer.
Medically reviewed.
Hepatitis B is a viral infection that damages the liver, caused by the hepatitis B virus (HBV). It spreads through contact with infected blood or body fluids, including unprotected sex, shared needles, and childbirth. Left untreated, chronic infection can progress to cirrhosis, liver failure, or liver cancer, especially in older adults and immunocompromised people.
Many people have no symptoms at all, especially with chronic infection, which is why routine blood testing matters for people at risk.
Children, older adults, and people with weakened immune systems are more likely to develop chronic hepatitis B, which can lead to cirrhosis, liver failure, or liver cancer if it goes unmanaged.
A safe, effective vaccine can prevent hepatitis B, and antiviral medications can control chronic infection and slow liver damage, even though they do not cure it.
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About hepatitis B
Hepatitis B is a viral disease that damages the liver. About 350 million people worldwide and more than 1.2 million people in the U.S. are infected with hepatitis B.
Hepatitis B is a blood-borne virus. Having chronic hepatitis B raises the risk of liver failure, liver cancer, or cirrhosis, a condition that permanently scars the liver.
Within the first six months of infection, hepatitis B can be cleared by the body or become chronic. Children, older adults, and people with weakened immune systems are the most likely to develop chronic hepatitis B.
The course of hepatitis B varies widely from person to person. Someone who clears the virus becomes immune to it. In rare cases, the virus can appear cleared but reactivate if the person later develops another illness, such as AIDS, or takes certain medications, such as immunosuppressants or chemotherapy.
How hepatitis B may feel
Signs and symptoms of hepatitis B vary widely from person to person. Many people with chronic hepatitis B have no symptoms at all until the infection has already progressed toward cirrhosis or liver cancer — fatigue is the most common sign of chronic hepatitis B.
Getting checked
Hepatitis B is diagnosed and monitored through a set of blood tests that detect different markers of the virus and the body's immune response to it.
A positive HBsAg blood test confirms a hepatitis B diagnosis.
Care & management
There is a safe and effective vaccine for hepatitis B, but there is currently no medication that cures an active infection. Treatment approach depends on whether the infection is acute or chronic.
Acute hepatitis B usually clears on its own without medicine within the first six months, although certain medications can help ease symptoms. If exposure is suspected within the last 24 hours, a doctor may give an injection to help prevent the virus from taking hold.
For chronic hepatitis B, a doctor may prescribe PEG-interferon therapy, which stimulates the immune system, or antiviral drugs such as nucleoside or nucleotide analogues (for example tenofovir or entecavir) that suppress the virus's ability to multiply. These medications do not eliminate the virus, but they can inhibit long-term viral activity and slow the disease's progress. Mild forms of chronic hepatitis B are often not treated; in fact, only about 1% of people with hepatitis B require treatment.
Antiviral nucleoside/nucleotide drugs do not offer a complete cure, but they help prevent further liver damage. Interferon therapy provides a 20-25% cure rate and a 25-45% rate of converting active infection into a persistent, less active state.
How hepatitis B spreads
Hepatitis B is a blood-borne virus that is about 100 times more infectious than HIV. It cannot be spread through kissing, hugging, or sharing food.
Hepatitis B is roughly 100 times more infectious than HIV, and it spreads only through contact with infected blood or body fluids.
When to get checked
Hepatitis B often causes no symptoms, especially in chronic infection, which means many people are unaware they have the condition until it is found during routine blood tests or screening for at-risk groups.
Talk with your doctor about hepatitis B testing if you have had unprotected sex with a person of unknown hepatitis B status, inject drugs or share needles, live with or care for someone who has hepatitis B, were born to a mother with hepatitis B, have had a tattoo or piercing done in unsanitary conditions, received a blood transfusion or organ transplant before 1992, or work in a setting with regular blood exposure.
If you suspect you were exposed to hepatitis B in the last 24 hours, contact a doctor right away — a preventive injection may help stop the virus from taking hold. If you already have chronic hepatitis B, seek prompt care for jaundice, abdominal swelling, confusion, or easy bruising, which can signal advancing liver damage.
People with hepatitis B, especially chronic infection, are often followed by a gastroenterologist or hepatologist who can monitor liver function, evaluate the need for antiviral treatment, and screen for complications such as cirrhosis or liver cancer.
Find doctors who treat hepatitis B and connect with a liver specialist near you.
Eating & liver health
Diet does not cure hepatitis B, but eating well supports your liver. A balanced, liver-healthy diet is low in fat, salt, and refined sugar. If your doctor prescribes antiviral medicine, it works best alongside a balanced diet and no alcohol.
Alcohol can worsen liver damage from chronic viral hepatitis, so ask your doctor about it. Limit fast food, sweets, and soft drinks, and avoid uncooked shellfish such as oysters and clams. Cook with olive or flaxseed oil instead of butter, and choose lean meats such as turkey or salmon.
Smaller meals every three to four hours can be easier to manage than a few large ones. Needs differ with the stage of liver disease, so check with your doctor or a dietitian.
Foods That Support Your Liver With Hepatitis B
Common questions
Hepatitis B is a viral infection that damages the liver, caused by the hepatitis B virus (HBV). It can cause a short-term (acute) illness or a long-term (chronic) infection. Chronic hepatitis B raises the risk of cirrhosis (permanent liver scarring), liver failure, and liver cancer. About 350 million people worldwide and more than 1.2 million people in the U.S. have it.
Hepatitis B spreads only through contact with infected blood or body fluids. This can happen from mother to unborn child, through unprotected sex with someone who has an active infection, through shared needles, and through unsanitary tattoo or piercing conditions. Sharing razors, tweezers, or toothbrushes with an infected person can also pass it on. It does not spread through kissing, hugging, or sharing food.
A blood test diagnoses hepatitis B. A positive hepatitis B surface antigen (HBsAg) result means you have a current infection. Other tests show whether the virus is active, whether you are immune, and how well treatment is working. A hepatitis B DNA test measures the virus in your blood, and high levels mean the virus is active and highly contagious. Ask your doctor about testing even if you feel well, because many people have no symptoms.
Sometimes. Acute hepatitis B often clears on its own within six months, and the person then becomes immune. If the infection lasts longer than six months, it becomes chronic, which is more likely in children, older adults, and people with weakened immune systems. No medication cures chronic hepatitis B, but antiviral drugs can control the virus and help prevent further liver damage.
No. Only about 1% of people with hepatitis B need treatment. A doctor may recommend it if you are at risk for liver disease, have cirrhosis, or have a weakened immune system. Treatment is usually an antiviral pill taken once a day for many years, or interferon injections given for six months to a year or longer. Your doctor will explain the benefits, side effects, and who should avoid each option.
Yes. The hepatitis B vaccine is safe and effective, with about a 95% success rate when given correctly. Adults typically receive three doses over six months, and infants and children receive three or four doses over six to 18 months. Protection is believed to last many years, and possibly a lifetime. The vaccine may work less well in people over 40, people who smoke or have obesity, and those who misuse alcohol or take immunosuppressive medicines.
Over time, untreated chronic hepatitis B can lead to cirrhosis, liver failure, or liver cancer. Many people have no symptoms until these complications develop, which is why regular monitoring matters. Seek prompt care for jaundice, swelling in your abdomen or legs, confusion, or easy bruising. A gastroenterologist or hepatologist can monitor your liver and screen for complications.
Medical disclaimer: LiverDirectory provides educational information and a directory of providers. It does not provide medical advice, diagnosis, or treatment. Always consult a licensed physician regarding any medical condition.
