Brand Name(s): | What is hepatitis B? | Hepatitis B vaccine: Why get vaccinated? | Who should get hepatitis B vaccine and when? | Who should not get hepatitis B vaccine? | What are the risks from hepatitis B vaccine? | What if there is a moderate or severe reaction? | The National Vaccine Injury Compensation Program | How can I learn more? | ahfsCopyRight

What is hepatitis B?

Hepatitis B is a serious infection that affects the liver. It is caused by the hepatitis B virus.

  • In 2009, about 38,000 people became infected with hepatitis B.
  • Each year about 2,000 to 4,000 people die in the United States from cirrhosis or liver cancer caused by hepatitis B.

Hepatitis B can cause:

Acute (short-term) illness:

This can lead to:

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

Chronic (long-term) infection:

Some people go on to develop chronic hepatitis B infection. Most of them do not have symptoms, but the infection is still very serious, and can lead to:

  • liver damage (cirrhosis)
  • liver cancer
  • death

Chronic infection is more common among infants and children than among adults. People who are chronically infected can spread hepatitis B virus to others, even if they don't look or feel sick. Up to 1.4 million people in the United States may have chronic hepatitis B infection.

Hepatitis B virus is easily spread through contact with the blood or other body fluids of an infected person. People can also be infected from contact with a contaminated object, where the virus can live for up to 7 days.

A baby whose mother is infected can be infected at birth; children, adolescents, and adults can become infected by:

  • contact with blood and body fluids through breaks in the skin such as bites, cuts, or sores
  • contact with objects that have blood or body fluids on them such as toothbrushes, razors, or monitoring and treatment devices for diabetes
  • having unprotected sex with an infected person
  • sharing needles when injecting drugs
  • being stuck with a used needle.

Who should get hepatitis B vaccine and when?

Children and Adolescents:

Babies normally get 3 doses of hepatitis B vaccine:

  • 1st Dose: Birth
  • 2nd Dose: 1 to 2 months of age
  • 3rd Dose: 6 to 18 months of age

Some babies might get 4 doses, for example, if a combination vaccine containing hepatitis B is used. (This is a single shot containing several vaccines.) The extra dose is not harmful.

Anyone through 18 years of age who didn't get the vaccine when they were younger should also be vaccinated.

Adults:

All unvaccinated adults at risk for hepatitis B infection should be vaccinated. This includes:

  • sex partners of people infected with hepatitis B
  • men who have sex with men
  • people who inject street drugs
  • people with more than one sex partner
  • people with chronic liver or kidney disease
  • people under 60 years of age with diabetes
  • people with jobs that expose them to human blood or other body fluids
  • household contacts of people infected with hepatitis B
  • residents and staff in institutions for the developmentally disabled
  • kidney dialysis patients
  • people who travel to countries where hepatitis B is common
  • people with HIV infection.
  • Other people may be encouraged by their doctor to get hepatitis B vaccine; for example, adults 60 and older with diabetes. Anyone else who wants to be protected from hepatitis B infection may get the vaccine.
  • Pregnant women who are at risk for one of the reasons stated above should be vaccinated. Other pregnant women who want protection may be vaccinated.

Adults getting hepatitis B vaccine should get 3 doses, with the second dose given 4 weeks after the first and the third dose 5 months after the second. Your doctor can tell you about other dosing schedules that might be used in certain circumstances.