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Hepatitis A Vaccine


Margot L. Savoy

, MD, MPH, Lewis Katz School of Medicine at Temple University

Reviewed/Revised Jul 2023

Use of the vaccine has reduced the number of people who become infected.

For more information, see the Centers for Disease Control and Prevention's (CDC) Hepatitis A vaccine information statement.

Administration of Hepatitis A Vaccine

The hepatitis A vaccine is given as an injection into a muscle. As a part of routine childhood vaccinations Childhood Vaccinations Vaccination protects children against many infectious diseases. Vaccines contain either noninfectious components of bacteria or viruses or whole forms of these organisms that have been weakened... read more , two doses are given to all children: typically at age 12 to 23 months and 6 to 18 months later. Unvaccinated adults can also receive this two-dose vaccine. After the first dose, people are fully protected for 6 to 12 months, and after the second dose, people are protected for at least 14 to 20 years. (See CDC: Child and Adolescent Immunization Schedule by Age).

A vaccine that combines hepatitis A and hepatitis B vaccine is also available. This vaccine is given as a series of three or four doses in people 18 years of age and older.

The hepatitis A vaccine is recommended for older children and adolescents who were not previously vaccinated. Unvaccinated adults who want to be protected from hepatitis A can also receive the vaccine.

The vaccine is also recommended for people who are at increased risk of getting hepatitis A infection, such as the following:

  • People who travel to or work in areas where the infection is common

  • People whose job puts them at risk of exposure (such as people who work with primates infected with hepatitis A virus or who work with the virus in a research laboratory)

  • People who use illicit drugs (injected or not)

  • Men who have sex with men

  • People who have a chronic liver disorder (such as hepatitis B, hepatitis C, cirrhosis, fatty liver disease, alcohol-related liver disease, and autoimmune hepatitis) or high levels of certain liver enzymes in their blood

  • Healthy adults 40 years of age or under who have recently been exposed to hepatitis A virus

  • People who are homeless

  • People who anticipate close contact with an adopted child during the first 60 days after the child arrives in the United States from an area where hepatitis A is common

  • Pregnant women who are at risk of getting hepatitis A infection during pregnancy (such as women who are international travelers, who use illicit drugs [injected or not], who may be exposed at work, who anticipate close personal contact with an international adopted child, or who are homeless) or who are at risk of getting very sick or dying of hepatitis A virus infection (such as women who have chronic liver disease or HIV infection)

During a hepatitis A outbreak, people 1 year of age or older who are at risk of hepatitis A virus infection should be vaccinated.

If people have a temporary illness, doctors usually wait to give the vaccine until the illness resolves (see also CDC: Who Should NOT Get Vaccinated With These Vaccines?).

Side Effects of Hepatitis A Vaccine

Sometimes the injection site is sore, red, and swollen. No serious side effects have been reported.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

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