Patient education: Hepatitis B (Beyond the Basics)

INTRODUCTION — The term "hepatitis" is used to describe a common form of liver injury. Hepatitis simply means "inflammation of the liver" (the suffix "itis" means inflammation and "hepa" means liver). Hepatitis B is a specific type of hepatitis that is caused by a virus.

It is estimated that there are more than 295 million carriers of the hepatitis B virus in the world, with over 800,000 dying annually from hepatitis B-related liver disease.

Fortunately, hepatitis B infection can be prevented by vaccination. Hepatitis B vaccines are safe and highly effective in preventing hepatitis B infection and are now given routinely to newborns and children in the United States and in many other countries (see "Patient education: Vaccines for adults (Beyond the Basics)"). For people who do develop chronic hepatitis B, several medications are available for treating the infection.

More detailed information about hepatitis B is available by subscription. (See 'Professional level information' below.)

HOW DID I BECOME INFECTED WITH HEPATITIS B? — There are several ways people become infected with hepatitis B virus.

Contaminated needles — Using contaminated needles can spread the hepatitis B virus. This can happen if people who use injection drugs share needles or syringes. It is also possible to spread hepatitis B through tattooing, acupuncture, or body piercing (if these procedures are done with contaminated instruments). You can lower your risk by making sure your practitioner follows careful sterilization procedures.

Sex — Sexual contact with someone who is infected is one of the most common ways to become infected with hepatitis B. If you are infected with hepatitis B and have a regular sexual partner(s), they should be tested for the infection and vaccinated if necessary.

Childbirth — Hepatitis B can be passed from a pregnant person to their baby during or shortly after childbirth. Having a Cesarean birth (also called a C-section) does not prevent the virus from spreading. Experts believe that breastfeeding is safe for people with hepatitis B.

To help prevent transmission from mother to infant, all pregnant people should have a blood test for a marker of hepatitis B virus, called hepatitis B surface antigen (HBsAg). Normally, the HbsAg should be negative. If the pregnant person is HbsAg-positive, they should be referred to a specialist. (See 'Preventing transmission to a baby during childbirth' below.)

Close contact — Hepatitis B can be spread through close personal contact. This could happen if blood or other bodily fluids get into tiny cracks or breaks in your skin or in your mouth or eyes. The virus can live for a long time away from the body, meaning that it can be spread by sharing household items like toys, toothbrushes, or razors. However, it is not spread through touching, shaking hands, or sharing a meal or cooking utensils. (See 'Preventing infection of close contacts' below.)

Blood transfusion and organ transplantation — Nowadays, it is extremely rare for hepatitis B to be spread through blood transfusion or organ transplantation. Blood and organ donors are carefully screened for markers of hepatitis infection. (See "Patient education: Blood donation and transfusion (Beyond the Basics)".)

In the hospital — In the hospital, hepatitis B virus can spread from one patient to another or from a patient to a doctor or nurse if there is an accidental needle stick. It is rare for a doctor/nurse to pass hepatitis B to a patient. Wearing gloves and washing hands can help to prevent spreading the virus. Discarding needles and syringes after use and proper sterilization of surgical equipment also prevents spread of the virus.

HEPATITIS B SCREENING — Experts recommend that all people age 18 years and older be screened at least once for hepatitis B. This is because the infection can lead to complications if a person does not know that they have it. Different tests can be used for screening. (See 'Hepatitis B diagnosis' below.)

Pregnant people should be rescreened for hepatitis B during each pregnancy. If a test shows that the person does have hepatitis B, there are steps that can be taken to lower the risk of transmitting hepatitis B to their baby. (See 'Preventing transmission to a baby during childbirth' below.)

Screening is not generally needed for people who have been fully vaccinated against hepatitis B and have a had a blood test confirming that they are immune to the virus.

HEPATITIS B SYMPTOMS — Symptoms due to hepatitis B vary. After a person is first infected with hepatitis B, they can develop a flu-like illness that includes fever, abdominal pain, fatigue, decreased appetite, nausea, and in some cases yellowing of the skin and eyes (jaundice). In the most severe cases, liver failure can develop, which is characterized by jaundice, fluid accumulation (swelling in the legs or abdomen), and confusion. However, many people do not develop symptoms, particularly if the infection occurs in infants and children. Not having symptoms does not necessarily mean the person is not infected or that the infection is under control. Most people with chronic hepatitis B have no symptoms until their liver disease is at a late stage. The most common early symptom is feeling tired. Everyone with chronic hepatitis B is at increased risk of developing complications, including liver scarring (called cirrhosis when the scarring is severe) and liver cancer. (See "Patient education: Cirrhosis (Beyond the Basics)".)

Acute hepatitis B — After a person is first infected with hepatitis B, they are said to have "acute" hepatitis. Most people with acute hepatitis B recover uneventfully.

However, in about 5 percent of adults (1 in 20) the virus makes itself at home in the liver, where it continues to make copies of itself for many years. People who continue to harbor the virus are referred to as "carriers". If liver damage develops because of longstanding infection, the person is said to have "chronic" hepatitis.

Chronic hepatitis B — Chronic hepatitis B develops more commonly in people who are infected with the virus at an early age (often at birth). Unfortunately, this is common in some parts of the world such as in Southeast Asia, China, and sub-Saharan Africa, where as many as 1 in 10 people have chronic hepatitis B infection.

Many people with chronic hepatitis B have no symptoms at all; other people have symptoms such as fatigue and loss of appetite.

HEPATITIS B DIAGNOSIS — There are a number of tests that can be used to diagnose or monitor hepatitis B infection. Most of these tests are blood tests and include those that detect:

●Hepatitis B surface antigen (abbreviated HBsAg) – HBsAg is a protein on the surface of the hepatitis B virus. This protein shows up in the blood 1 to 10 weeks after exposure to the hepatitis B virus and before a person starts to show symptoms of the infection. In people who recover, this protein usually disappears after 4 to 6 months. Its continued presence suggests that chronic infection has developed.

●Hepatitis B surface antibody (abbreviated anti-HBs) – Anti-HBs helps the body's immune system attack the hepatitis B virus. This protein is usually present in people who have recovered or who have been vaccinated against hepatitis B. People with this protein are usually immune to hepatitis B.

●Hepatitis B core antibody (abbreviated anti-HBc) – Anti-HBc is usually present throughout the course of infection and stays in the blood after recovery. Its presence indicates current or past infection. It is not present in people who have been vaccinated against hepatitis B.

●Hepatitis B e antigen (abbreviated HBeAg) – HBeAg is a protein whose presence indicates that the hepatitis B virus is continuing to make copies of itself (replicating). Its presence usually indicates a high level of circulating virus and a high chance of transmission of infection. Its absence usually indicates a lower level of circulating virus.

●Hepatitis B e antibody (abbreviated anti-HBe) – Anti-HBe usually signifies that virus replication has slowed down, but in some variants of hepatitis B, the virus continues to replicate at a rapid rate, and high levels of virus can be found in the circulation.

●Hepatitis B DNA (abbreviated HBV DNA) – HBV DNA is the genetic material found in the hepatitis B virus. The HBV DNA "viral load" is a measure of the concentration of virus in the circulating blood.

HBV DNA usually disappears from the blood after a person recovers from acute infection. In people with chronic hepatitis B infection, HBV DNA levels in the blood can vary depending on the balance between the person's immune system trying to control the virus and the virus trying to replicate (make more copies of itself).

In people with chronic hepatitis B infection, doctors use the levels of HBV DNA to decide who needs treatment with antiviral medicines and to track how well treatment is working.

●Other tests – There are many other tests that can reflect the health of the liver, but are not specific for hepatitis B. These include liver enzyme tests (alanine aminotransferase [ALT] and aspartate aminotransferase [AST]), bilirubin, alkaline phosphatase, albumin, prothrombin time, and platelet count. As an example, an abnormally high ALT in the blood indicates liver damage. Although liver damage can be caused by a virus (such as hepatitis B virus), it can also be caused by alcohol, drugs, fat accumulation in the liver ("fatty liver"), or other diseases.

A liver biopsy (in which a needle is inserted into the liver to remove a small piece of tissue for testing) is not routinely needed to diagnose hepatitis B virus infection. A liver biopsy is used to monitor liver damage in people with chronic hepatitis, help decide if treatment is needed, and find signs of cirrhosis or liver cancer. (See "Patient education: Liver biopsy (Beyond the Basics)".)

The severity of liver disease or degree of liver damage can also be determined by other methods, without the need for liver biopsy. This may involve blood tests or tests to measure liver stiffness. In general, these tests are accurate in being able to tell early fibrosis (scarring) from advanced fibrosis or cirrhosis (when the scar tissue is severe). However, they cannot determine specific stages of fibrosis or determine the degree of inflammation.

WILL I DEVELOP CHRONIC HEPATITIS B? — The likelihood of developing chronic hepatitis B largely depends on your age at the time of infection. Chronic infection develops in about 90 percent of children who are infected at birth, in 20 to 50 percent of children who are infected between the ages of 1 and 5 years, and in less than 5 percent of people infected with hepatitis B during adulthood.

AM I AT RISK OF GETTING CIRRHOSIS OR LIVER CANCER? — The risk of developing complications (such as cirrhosis, liver failure, or liver cancer) depends on how rapidly the virus multiplies and how well your immune system controls the infection.

For people with chronic hepatitis B, the risk of developing complications is:

●Higher in men than in women, and with increasing age.

●Increased by drinking alcohol, having chronic hepatitis C or D (a virus that is dependent on hepatitis B), or having HIV infection (the virus that causes AIDS).

In addition, being overweight or having diabetes increases the risk of having fatty liver (fat accumulation in the liver), which can increase the rate of liver disease progression in people with hepatitis B.

HEPATITIS B TREATMENT

Should everyone be treated? — Specific treatment for acute hepatitis B is usually not needed since in about 95 percent of adults, the immune system controls the infection and gets rid of the virus within about six months.

In people who develop chronic hepatitis, an antiviral medication might be recommended to reduce or reverse liver damage and to prevent long-term complications of hepatitis B. However, not everyone with hepatitis B needs immediate treatment. If you do not need to start treatment immediately, you will be monitored over time to know when hepatitis becomes more active (at that point you may begin antiviral treatment).

Once you start treatment, you will have regular blood tests to see how well the treatment is working and to detect side effects or drug resistance. Monitoring will continue after finishing treatment to determine if the infection has come back. Treatment should not be stopped without discussing this with your doctor because, in some cases, the virus can come back quickly, causing severe liver injury.

Antiviral medications — If your doctor thinks you should be treated, there are two types of antiviral medications that can be used, nucleos(t)ide analogs (these are oral medications that you take daily) and interferon (an injectable medication). Most people receive an oral medication; however, your doctor will discuss these choices with you.

Nucleos(t)ide analogs — Nucleos(t)ide analogs are oral antiviral medications that can be used to treat hepatitis B. In some people with advanced cirrhosis, treatment with one of these medications can reverse liver failure and eliminate the need for liver transplantation. (See 'Liver transplantation' below.)

Entecavir and tenofovir are the most commonly used oral antiviral medications. These medications are more potent and are less likely to cause the virus to develop resistance compared with nucleos(t)ide analogs that were previously used (eg, lamivudine). (See 'Entecavir' below and 'Tenofovir' below.)

Most people will need long-term treatment to maintain control of the hepatitis B virus. In some cases, lifelong therapy is needed.

Entecavir — Entecavir (brand name: Baraclude) is a recommended treatment for people who have not been treated with oral antivirals before. Although resistance to entecavir is uncommon in people who have never received antiviral therapy, it can occur in up to 50 percent of people who have used lamivudine for treatment of hepatitis B.

Tenofovir — Tenofovir is a recommended treatment for both people who have been and those who have never been treated with oral antivirals for hepatitis B. Tenofovir is available in two formulations: tenofovir disoproxil fumarate (brand name: Viread) and tenofovir alafenamide (brand name: Vemlidy). For most people, tenofovir alafenamide is preferred, if it is available.

Tenofovir is effective in suppressing hepatitis B virus that is resistant to other antiviral agents, such as lamivudine, telbivudine, adefovir, or entecavir. Resistance to tenofovir has not been reported.

Pegylated interferon-alfa — Pegylated interferon-alfa is an appropriate treatment for people with chronic hepatitis B infection who have detectable virus activity, ongoing liver inflammation, and no cirrhosis.

Pegylated interferon-alfa may be considered in young people who do not have advanced liver disease and do not wish to be on long-term treatment. It is not appropriate for people with cirrhosis who have liver failure or for people who have a recurrence of hepatitis after liver transplantation.

Pegylated interferon is an injection taken once a week, and it is given for one year. This is in contrast to the other hepatitis treatments, which are given by mouth for many years until a desired response is achieved. Drug resistance to interferon has not been reported.

The disadvantage of pegylated interferon-alfa is that it can cause many side effects.

Liver transplantation — In some cases, liver transplantation may be the only option for people who have developed advanced cirrhosis. The liver transplantation process involves an extensive screening process to ensure that a person is a good candidate. Thus, not all people with cirrhosis are eligible, and only those with the most advanced cirrhosis or early stage liver cancer and otherwise good medical and social conditions will be put on the transplant waiting list. Because of the shortage of donors, not everyone on the transplant waiting list will receive a liver transplant.

TIPS TO MAINTAIN LIVER HEALTH — As discussed above, the majority of people with acute hepatitis B spontaneously clear the infection. Those who develop chronic infection should see a doctor with expertise in liver disease (usually a gastroenterologist or hepatologist) who can discuss treatment options.

Vaccinations — Everyone with chronic hepatitis B should be vaccinated against hepatitis A unless they are known to be immune. Influenza vaccination is recommended once per year, usually in the fall.

People with chronic hepatitis B should be vaccinated against SARS-CoV2 (the virus that causes COVID-19). The COVID vaccines are safe for people with chronic hepatitis B. People with cirrhosis may have more severe illness if they get COVID-19, and some medications used to treat severe COVID-19 may make hepatitis B virus more active.

People with liver disease should also receive other standard immunizations, including a diphtheria and tetanus booster, every 10 years. (See "Patient education: Vaccines for adults (Beyond the Basics)".)

Liver cancer screening — Regular screening for liver cancer is also recommended, particularly for older individuals, those with cirrhosis, and people with a family history of liver cancer. In general, this includes an ultrasound examination of the liver plus a blood test for alpha-fetoprotein (AFP) every six months.

Diet — No specific diet has been shown to improve the outcome in people with hepatitis B. The best advice is to eat a normal healthy and balanced diet and to maintain a normal weight. (See "Patient education: Diet and health (Beyond the Basics)".)

Alcohol — Alcohol should be avoided since it can worsen liver damage. All types of alcoholic beverages can be harmful to the liver. People with hepatitis B can develop liver complications even with small amounts of alcohol.

Smoking — Smoking is harmful for your health and should be avoided. In addition, smoking has been shown in some studies to increase the risk of liver cancer in people with hepatitis B. (See "Patient education: Quitting smoking (Beyond the Basics)".)

Exercise — Exercise is good for overall health and is encouraged, but it has no effect on the hepatitis B virus. Exercise is not harmful to the liver, even in people with chronic hepatitis or cirrhosis.

Prescription and nonprescription drugs — Many medications are broken down by the liver. Thus, it is always best to check with a healthcare provider or pharmacist before starting a new medication. As a general rule, unless the liver is already scarred, most drugs are safe for people with hepatitis B.

An important possible exception is acetaminophen (sample brand name: Tylenol); the maximum recommended dose in people with liver disease is no more than 2 grams (2000 mg or four extra strength tabs or capsules) in 24 hours. Most acetaminophen tabs or capsules contain 325 or 500 mg. Many over-the-counter cold and headache medicines under different names may contain acetaminophen.

You should avoid ibuprofen (sample brand names: Advil, Motrin), naproxen (sample brand name: Aleve), and aspirin if you have cirrhosis.

Herbal medications — No herbal treatment has been proven to improve outcomes in people with hepatitis B, and some can cause serious liver toxicity. Herbal treatments are not recommended for anyone with hepatitis B.

Support — Some people find it helpful to connect with and get support from others living with hepatitis B. A number of organizations are available around the world. (See 'Where to get more information' below.)

PREVENTION

Preventing infection of close contacts — Acute and chronic hepatitis B are contagious. Thus, people with hepatitis B should discuss measures to reduce the risk of infecting close contacts. This includes the following:

●Discuss the infection with any sexual partners and use a latex condom with every sexual encounter (unless the sexual partner(s) is known to be immune to hepatitis B).

●Do not share razors, toothbrushes, or anything that might have blood on it.

●Cover open sores and cuts with a bandage.

●Do not donate blood, body organs, other tissues, or sperm.

●Immediate family, household members, and regular sexual partners should be tested for hepatitis B. Anyone who is at risk of hepatitis B infection should be vaccinated. (See "Patient education: Vaccines for adults (Beyond the Basics)".)

●Do not share any injection drug equipment (needles, syringes).

●Clean blood spills with a mixture of 1 part household bleach to 9 parts water.

Hepatitis B cannot be spread by:

●Hugging or kissing

●Sharing eating utensils or cups

●Sneezing or coughing

●Breastfeeding

Preventing transmission to a baby during childbirth — If a pregnant person tests positive for hepatitis B surface antigen, certain steps can be taken to decrease the risk of transmitting the virus to their baby

. These include:

●Antiviral medications – Antiviral medications may be recommended for the mother if the amount of virus in her blood (viral load) is high. These medications are used to decrease the viral load. You may be referred to a specialist to help decide if you need medications and what medications to use.

●Hepatitis B immunoglobulin – Infants should be given a shot soon after birth called hepatitis B immunoglobulin (HBIG). HBIG provides immediate protection to the infant, but the effect only lasts a few months.

●Hepatitis B immunizations – Infants should also receive the hepatitis B vaccine series. Completing the vaccine series is important for long-term protection.

The first dose of hepatitis B vaccine should be given at birth. In some countries (including the United States), two other doses are typically required to complete the vaccine series; these can be administered along with their regular childhood immunizations at approximately 1 and 6 months of age. However, in other countries, children routinely receive three doses of the hepatitis B vaccine in addition to the birth dose (ie, a total of four doses).

These infants should have a blood test for hepatitis B surface antigen and for hepatitis B surface antibody at 9 to 12 months of age or one to two months after the last dose of hepatitis B vaccine if immunization is delayed. If the results of the antibody test are negative, additional vaccination is needed.

Preventing HBV reactivation — If a person with chronic HBV infection needs to take medications that suppress their immune function, HBV can reactivate (multiply very quickly) and cause damage to the liver. These types of medications include cancer chemotherapy, high dose steroids, and other "immunosuppressive" medications that may be used to treat conditions such as Crohn's disease, rheumatoid arthritis, and psoriasis.

Reactivation of HBV can be prevented by taking an HBV antiviral medication (see 'Antiviral medications' above). If you are diagnosed with a new health condition or prescribed a new medication, it is important to let all your doctors know that you have hepatitis B, so they can make sure you are treated properly or refer you to a specialist if needed.

WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem.

This article will be updated as needed on our web site (www.uptodate.com/patients). Related topics for patients, as well as selected articles written for healthcare professionals, are also available. Some of the most relevant are listed below.

Patient level information — UpToDate offers two types of patient education materials.

The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.

Patient education: Hepatitis B (The Basics)
Patient education: Cirrhosis (The Basics)
Patient education: Blood or body fluid exposure (The Basics)
Patient education: Liver transplant (The Basics)
Patient education: Treatment for hepatitis C (The Basics)

Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon.

Patient education: Vaccines for adults (Beyond the Basics)
Patient education: Blood donation and transfusion (Beyond the Basics)
Patient education: Cirrhosis (Beyond the Basics)
Patient education: Liver biopsy (Beyond the Basics)

Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings. These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based. Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading.

Characteristics of the hepatitis B virus and pathogenesis of infection
Hepatitis B virus: Clinical manifestations and natural history
Clinical significance and molecular characteristics of common hepatitis B virus variants
Clinical significance of hepatitis B virus genotypes
Epidemiology, transmission, and prevention of hepatitis B virus infection
Hepatitis B virus immunization in adults
Immunizations for adults with chronic liver disease
Hepatitis B virus: Overview of management
Hepatitis B virus: Screening and diagnosis in adults
Pegylated interferon for treatment of chronic hepatitis B virus infection
Treatment of chronic hepatitis B in patients with HIV
Entecavir in the treatment of chronic hepatitis B virus infection
Tenofovir and adefovir for the treatment of chronic HBV infection

The following organizations also provide reliable health information.

●National Library of Medicine

     (www.nlm.nih.gov/medlineplus/healthtopics.html)

●Centers for Disease Control

     (www.cdc.gov/ncidod/diseases/hepatitis/index.htm)

●National Institute of Diabetes and Digestive and Kidney Diseases

     (www.niddk.nih.gov)

●National Institute of Allergy and Infectious Diseases

     (www.niaid.nih.gov/)

●National Foundation for Infectious Diseases

     (www.nfid.org)

●American Association for Study of Liver Diseases

     (www.aasld.org)

●American Gastroenterological Association

     (www.gastro.org)

●American Liver Foundation

     (www.liverfoundation.org)

●The Hepatitis B Foundation

     (www.hepb.org)

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