Hepatitis B Vaccine

What you need to know

About the Disease

Hepatitis B is a serious disease

The hepatitis B virus can cause short-term (acute) illness that leads to:

  • loss of appetite
  • diarrhea and vomiting
  • tiredness
  • jaundice (yellow skin or eyes)
  • pain in muscles, joints and stomach

It can also cause long-term (chronic) illness that leads to:

  • liver damage (cirrhosis)
  • liver cancer
  • death

About 1.25 million people in the US have chronic hepatitis B virus infection

Each year it is estimated that:

  • 200,000 people, mostly young adults, get infected with hepatitis B virus
  • More than 11,000 people have to stay in the hospital because of hepatitis B
  • 4,000 to 5,000 people die from chronic hepatitis B

Hepatitis B vaccine can prevent hepatitis B. It is the first anti-cancer vaccine because it can prevent a form of liver cancer.

How the disease is spread

Hepatitis virus is spread through contact with the blood and body fluids of an infected person. A person can get infected in several ways, such as:

  • during birth when the virus passes from an infected mother to her baby
  • by having sex with an infected person
  • by injecting illegal drugs
  • by being stuck with a used needle on the job
  • by sharing personal items, such as a razor or toothbrush with an infected person

People can get hepatitis B virus infection without knowing how they got it. About one third of hepatitis B cases in the United States have an unknown source.

Who should get the vaccine

  • Everyone 18 years of age and younger
  • Adults over 18 who are at risk

Adults at risk for hepatitis B virus infection include people who have more than one sex partner, men who have sex with other men, injection drug users, health care workers, and other who might be exposed to infected blood or body fluids.

Dosing Schedule

People should get 3 doses of hepatitis B vaccine according to the following schedule: if you miss a dose or get behind schedule, get the next dose as soon as you can. There is no need to start over.

Infant whose mother is infected with Hep B virus

  • first dose: within 12 hours of birth
  • second dose: 1-2 months of age
  • third dose: 6 months of age

Infant whose mother is not infected with Hep B virus

  • first dose: Birth- 2 months of age
  • second dose: 1-4 months of age, and at least 4 weeks after first dose
  • third dose: 6-18 months of age

Older child, adolescent or adult

  • first dose: anytime
  • second dose: 1-2 months after first dose
  • third dose: 4-6 months after first dose

other timing issues

  • The second dose must be given at least one month after the first dose
  • The third dose must be given at least 2 months after the second dose and at least 4 months after the first
  • The third dose should not be given to children younger than 6 months of age
  • All three doses are needed for full and lasting immunity
  • Hepatitis B vaccine may be given at the same time as other vaccines


People should not get hepatitis B vaccine if they have ever had a life-threatening reaction to baker's yeast (the kind used for baking bread) or to a previous dose of hepatitis B vaccine.

People who are moderately or severely ill at the time the shot is scheduled should usually wait until they recover before getting hepaitis B vaccine.

Risks from the Vaccine

A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions. The risk of hepatitis B vaccine causing harm, or death, is extremely small.

Getting hepatitis B vaccine is much safer than getting hepatitis B disease.

Most people who get hepatitis B vaccine do not have any problems with it.

mild problems

  • soreness where the shot was given, lasting a day or two ( up to 1 out of 11 children and adolescents, and 1 of 4 adults)
  • mild to moderate fever (up to 1 out of 14 children and adolescents and 1 out of 100 adults)

Severe problems

  • serious allergic reaction (very rare)

What if there is a reaction?

Look for any unusual condition, such as serious allergic reaction, high fever or behavior changes. Signs of a serious allergic reaction can include difficulty breathing, hoarseness and wheezing, hives, paleness, weakness, a fast heartbeat or dizziness. If such a reaction were to occur, it would be within a few minutes to a few hours after the shot.

If this should happen:

  • Call a doctor or get the person to a doctor right away.
  • Tell your doctor what happened, the date and time it happened and when the vaccination was given

information from the CDC, Department of Health and Human Services