Hepatitis B – immunization

Hepatitis B is a virus that can cause liver disease and, over time, liver cancer. Most adults who contract hepatitis B recover completely and do not need ongoing treatment. Children who are infected are more likely to develop chronic hepatitis B, defined as infection that persists for at least 6 months, which can lead to liver disease later in life.

Vaccination is the best protection against hepatitis B infection. All children should be vaccinated against hepatitis B, and adults at increased risk should be vaccinated too.

How hepatitis B spreads#

Mothers living with hepatitis B can pass the virus to their baby at the time of birth if no precautions are taken. The virus can also spread when broken skin or mucous membranes are exposed to the blood or other body fluids of an infected person.

Babies born to mothers with hepatitis B are recommended a dose of hepatitis B vaccine soon after birth, together with hepatitis B immunoglobulin. These two injections give extra protection to babies born to women living with the virus.

Symptoms#

Many people living with hepatitis B have no symptoms. Babies and children who are infected are less likely than adults to have symptoms, but they are more likely to develop chronic hepatitis B. When symptoms do occur, they may include:

• fever
• tiredness
• loss of appetite
• nausea and vomiting
• yellowing of the skin and eyes (jaundice)
• aching muscles and joints, and abdominal pain

A child who develops chronic hepatitis B has an increased risk of long-term liver disease and cancer later in life. Only a small proportion of adults who contract the virus go on to develop chronic infection.

Immunization for children#

A full course of hepatitis B injections is needed for a child to be protected. The course usually begins around birth with a vaccine against hepatitis B alone, given as soon as possible after delivery. Further doses are then given during infancy, often as part of a combination vaccine that also protects against other diseases. Vaccination may be with a vaccine against hepatitis B alone or as a combination vaccine.

The exact schedule and ages differ from country to country, so follow the schedule recommended by your local immunization provider. Premature babies may receive additional doses depending on their gestational age and birth weight.

Immunization for adults at increased risk#

Vaccination is recommended for all infants and young children, adolescents and people in high-risk groups. Depending on local programs, free or subsidised vaccine may be available for some groups at higher risk, which can include:

• people in or recently released from custodial settings who did not complete a course
• people from regions where hepatitis B is common, and some populations with higher rates of infection
• men who have sex with men
• people living with HIV or hepatitis C
• household contacts and sexual partners of people living with hepatitis B
• people who inject drugs or are on opioid substitution therapy
• refugee and humanitarian entrants
• solid organ and stem cell transplant recipients, and people who are immunocompromised
• people with chronic liver disease or a liver transplant
• people with vulnerabilities that have prevented earlier access to the vaccine

Immunization is also recommended for other people at increased risk, although it may not be free, including:

• adults on hemodialysis and people with severely impaired kidney function who may need dialysis
• workers who come into regular contact with blood or tissue, such as funeral workers, embalmers and tattooists
• other people who regularly contact human tissue, blood, body fluids or used needles
• travelers to areas where hepatitis B is common, especially for long or frequent visits or higher-risk activities

The adult course typically involves 3 doses over about 6 months and protects roughly 95% of people. After the 3 doses you can have a blood test to check whether you are protected.

If you think you have been exposed#

If you think you have been exposed to hepatitis B, see a doctor immediately. In some cases your doctor can give you treatment that greatly reduces your risk of infection.

Remember that being immunized against hepatitis B does not protect you against HIV, hepatitis C or other diseases spread by blood or body fluids. It is important to take precautions to avoid exposure to these diseases as well.

Before immunization#

Tell your immunization provider if you (or your child):

• are unwell, with a temperature over 38.5°C (101.3°F)
• have had a serious reaction to any vaccine or to any component of a vaccine
• have had a severe allergy to anything
• are pregnant or intend to become pregnant — hepatitis B vaccine is not usually recommended during pregnancy

Side effects#

Vaccines that protect against hepatitis B, including combination vaccines, are effective and safe, although all medicines can have unwanted effects. Side effects are uncommon and usually mild, and may include:

• localised pain, redness, itching, swelling or burning at the injection site, sometimes a small lump (nodule) that can last several weeks
• a low-grade fever
• in children, being unsettled, irritable, drowsy or generally unhappy

Common side effects are usually mild and short-lived, occurring in the first few days after vaccination, and specific treatment is not usually needed. To ease discomfort you can drink extra fluids and avoid overdressing if there is a fever. Routine use of paracetamol after vaccination is not recommended, but if fever is present paracetamol can be taken — check the label for the correct dose, or ask your pharmacist, especially before giving it to children.

If a side effect is unexpected, persistent or severe, or you are worried about yourself or your child after a vaccination, see your doctor or immunization nurse promptly, or go directly to a hospital. It is important to seek advice if you or your child are unwell, as this may be due to another illness rather than the vaccination. Ask your immunization provider how to report a suspected vaccine side effect in your area.

Rare side effects#

There is a very rare risk of a serious allergic reaction (anaphylaxis) to any vaccine. This is why you are advised to stay at the clinic for at least 15 minutes after immunization, in case further treatment is needed. If you think your child is having a serious allergic reaction and you have already left the clinic, take them immediately to a doctor or the nearest hospital, or call your local emergency number (for example 911 in the US and Canada, 112 across the EU and many countries, 999 in the UK, or 000 in Australia) for an ambulance.

Another rare side effect is a hypotonic-hyporesponsive episode (HHE), in which a baby may become pale, limp and unresponsive. This can occur from 1 to 48 hours after vaccination and may last from a few minutes to 36 hours. If you think your child is having an HHE episode, take them immediately to a doctor or the nearest hospital. Follow-up of children who have had HHE shows no long-term neurological or other effects.

Deciding which immunizations you need#

The immunizations you may need depend on your health, age, lifestyle and occupation — together referred to as HALO. Talk to your doctor or immunization provider if you think you, or someone in your care, has health, age, lifestyle or occupation factors that could make immunization necessary.

Key points#

• Most adults who contract hepatitis B recover completely and do not require ongoing treatment.
• Vaccination is the best protection against hepatitis B; all children, and adults at increased risk, should be vaccinated.
• Many people living with hepatitis B have no symptoms.
• The virus can spread from mother to baby at birth and through contact with infected blood or body fluids.
• If you think you have been exposed, see a doctor immediately, as early treatment can greatly reduce your risk of infection.

Where to get help#