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Hepatitis A (HepA) Vaccine


Margot L. Savoy

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

Last full review/revision Oct 2020| Content last modified Oct 2020
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Both hepatitis A vaccines provide long-term protection against hepatitis A.


Hepatitis A (HepA) vaccines are prepared from formalin-inactivated, cell culture–derived hepatitis A virus. There are 2 hepatitis A vaccines (Havrix® and Vaqta®); both are available in pediatric and adult formulations.

A vaccine that combines hepatitis A and hepatitis B vaccine (Twinrix®) is also available.


The HepA vaccine is a routine childhood vaccination (see Table: Recommended Immunization Schedule for Ages 0–6 Years).

HepA vaccine also is indicated when any of the following is present:

  • A desire for protection from hepatitis A in people not previously vaccinated

  • Travel to or work in endemic areas

  • Occupational exposure (eg, working with primates infected with hepatitis A virus [HAV] or HAV in a research laboratory)

  • Sex between men

  • Use of illicit drugs (injected or not), such as methamphetamine

  • Homelessness

  • HIV infection in all people ≥ 1 year of age

  • A chronic liver disorder (eg, people with hepatitis B, hepatitis C, cirrhosis, fatty liver disease, alcohol-related liver disease, autoimmune hepatitis, or alanine aminotransferase [ALT] or aspartate aminotransferase [AST] level greater than twice the upper limit of normal)

  • Anticipated close personal contact (eg, as members of the household or as regular babysitters) with an adopted child during the first 60 days after the child's arrival in the US from an endemic area

  • Healthy adults ≤ 40 years who have recently been exposed to hepatitis A virus and adults > 40 if hepatitis A immunoglobulin cannot be obtained

  • Pregnant women who are identified to be at risk of HAV infection during pregnancy (eg, women who are international travelers, who use illicit drugs [injected or not], who have occupational exposure risk, who anticipate close personal contact with an international adoptee, or who are homeless) or who are at risk of having a severe outcome resulting from HAV infection (eg, women who have chronic liver disease or HIV infection)

During hepatitis A outbreaks, people ≥ 1 year of age who are at risk of HAV infection should be vaccinated.

The combination HepA and HepB vaccine can be used in people ≥ 18 years who have indications for either hepatitis A or hepatitis B vaccine and who have not been previously vaccinated with one of the vaccine components.

Contraindications and Precautions

The main contraindication for HepA vaccine is

  • A severe allergic reaction (eg, anaphylaxis) after previous dose or to a vaccine component

The main precaution with HepA vaccine is

  • Moderate or severe illness with or without a fever (vaccination is postponed until the illness resolves)

Dose and Administration

The HepA vaccine dose is 0.5 mL IM up to age 18 years or 1 mL IM for adults (age ≥ 19 years).

Children are given a 2-dose series typically at age 12 to 23 months and 6 to 18 months after the 1st dose.

Adults are given the vaccine in a 2-dose series at 0 and 6 to 12 months (Havrix®) or 0 and 6 to 18 months (Vaqta®).

Or adults may be given the combination HepA and HepB vaccine on a 3-dose schedule: at 0, 1, and 6 months. The 1st and 2nd doses should be separated by ≥ 4 weeks, and the 2nd and 3rd doses should be separated by ≥ 5 months. Alternatively, the vaccine may be given on an accelerated 4-dose schedule: on days 0, 7, and 21 to 30, followed by a booster 12 months after the 1st dose.

As soon as an adoption of a child from an endemic area is planned, close contacts should be given the 1st dose of the 2-dose HepA vaccine series, ideally ≥ 2 weeks before the adopted child arrives.

Adverse Effects

No serious adverse effects have been reported.

Mild effects include pain, erythema, swelling, and occasionally induration at the injection site.

More Information

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

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