Hepatitis B is a serious disease that affects the liver. It is caused by the hepatitis B virus (HBV). Hepatitis B virus is spread through contact with the blood or other body fluids of an infected person. A person can become infected by:

  • having unprotected sex with an infected person
  • sharing needles when injecting drugs
  • contact with blood and body fluids through breaks in the skin such as bites, cuts, or sores
  • contact with objects that could have blood or body fluids on them such as toothbrushes or razors
  • stick with a used needle on the job
  • contact with a mother’s blood and body fluids at the time of birth 

HBV can cause acute (short-term) illness. This can lead to:

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

Acute illness is more common among adults. Children who become infected usually do not have acute illness.

Chronic (long-term) infection. Some people go on to develop chronic HBV infection. This can be very serious, and often leads to:

  • liver damage (cirrhosis)
  • liver cancer
  • death

Chronic infection is more common among infants and children than among adults. People who are infected can spread HBV to others, even if they don’t appear sick.

Who should be vaccinated for hepatitis B?

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

  • sex partners of people infected with HBV
  • 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 with jobs that expose them to human blood
  • residents and staff in institutions for the developmentally disabled
  • kidney dialysis patients

Hepatitis B vaccine can prevent hepatitis B, and the serious consequences of HBV infection, including liver cancer and cirrhosis.

Hepatitis B vaccine is made from a part of the hepatitis B virus. It cannot cause HBV infection. Hepatitis B vaccine is usually given as a series of 3 or 4 shots. This vaccine series gives long-term protection from HBV infection, possibly lifelong.

How can I learn more?

  • Ask your doctor or nurse. They can give you the vaccine package insert or suggest other sources of information. 
  • Contact the County of San Diego Health and Human Services Agency Immunization Branch
    • Call 1-866-358-2966
  • Contact the California Department of Public Health
    • Call 1-916-558-1784
  • Contact the Centers for Disease Control and Prevention
    • Call 1-800-232-4636
  •  Visit www.cdc.gov/hepatitis or www.cdc.gov/vaccines


Adapted from the Centers for Disease Control and Prevention’s Hepatitis B Vaccine Information Statement: http://www.cdc.gov/vaccines/pubs/vis/downloads/vis-hep-b.pdf