Hepatitis A Vaccine

Hepatitis A vaccine is a routine childhood vaccination. Typically 1 dose is given at age 12 to 23 months and the second dose is given 6 to 18 months later. Unvaccinated adults can also receive this 2-dose vaccine. (See Centers for Disease Control and Prevention [CDC]: Recommended Immunizations for Birth Through 6 Years Old, United States, 2025 and see CDC: Recommended Immunizations for Adults Aged 19 Years and Older, United States, 2025.)

All children should be given hepatitis A 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.

The hepatitis A vaccine is recommended for older children and adolescents who were not previously vaccinated.

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

• People who are experiencing homelessness

• People who have HIV infection

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

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

Unvaccinated adults who want to be protected from hepatitis A can also receive the vaccine, even without having any risk factors.

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

The combination vaccine can be used in people 18 years of age and older who have a need for either hepatitis A or hepatitis B vaccine and who have not been previously vaccinated with either one. People are given 3 or 4 doses.

People who have had a serious, life-threatening allergic reaction (such as an anaphylactic reaction) to any component in a hepatitis A vaccine should not receive it.

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?).