Hepatitis B is a highly contagious, serious liver disease caused by the hepatitis B virus. It is spread through contact with the blood or other body fluids of an infected person, including contact with objects that could have blood or body fluids on them such as toothbrushes and razors. The hepatitis B virus can cause:

• Acute (short-term) illness, the symptoms of which are flu-like and include loss of appetite, tiredness, joint and muscle pain, diarrhea, vomiting, and jaundice. Most adults who get hepatitis B have this acute form of hepatitis B, and then get better.

• Chronic (long-term) infection which can be very serious, and often leads to liver damage, liver cancer or death. Babies and young children infected with hepatitis B are more likely to get this chronic form of the disease.

The hepatitis B vaccine is the best way to prevent infection. It is a series of 2, 3, or 4 shots usually given over a 6–12- month period. It is given by an injection into the arm muscle of adolescents and adults and the thigh muscle of infants and young children. Estimates of long-term protection for those getting the full vaccination series suggest that protection from hepatitis B could last for up to 20 or 30 years and possibly for life.

The hepatitis B vaccine is recommended for all infants, all children or adolescents younger than 19 years of age who have not been vaccinated, all adults ages 19 through 59 years, and adults ages 60 years or older with risk factors for hepatitis B infection. Adults who are 60 years or older without known risk factors for hepatitis B may also receive a hepatitis B vaccine.

People at an increased risk from hepatitis B include:

• Those whose sex partner is infected with hepatitis B

• Men who have sex with men

• People with more than one sex partner

• Users of injection and non-injection drugs

• People with chronic liver or kidney disease

• Kidney dialysis patients

• People with HIV

• People with jobs that expose them to human blood

• Household contacts of people infected with hepatitis B

• Residents and staff in institutions for the developmentally disabled

• People with hepatitis C infection

• People who travel to countries where hepatitis B is common

Pregnant people who need protection from hepatitis B may be vaccinated but should check with their doctor first.

• Anyone with a life-threatening allergy to yeast, or to any component of the vaccine should not get the hepatitis B vaccine

• Anyone who has had a life-threatening allergic reaction to a previous dose of hepatitis B vaccine should not get another dose

• Anyone with moderate or severe illness should wait until they recover to be vaccinated

Mild-to-moderate side effects:

• Soreness, redness, or swelling at the injection site

• Tiredness

• Headache

• Fever

Severe side effects, although rare, may include serious allergic reactions. Symptoms include:

• Difficulty breathing

• Wheezing

• Hives

• Pale skin

• Fast heartbeat

• Dizziness

Over-the-counter pain relievers such as paracetamol or ibuprofen can help ease pain and reduce fever. Contact your doctor or pharmacist if you have any unexpected or worsening reactions after receiving a vaccine.