Both hepatitis A vaccines provide long-term protection against hepatitis A Hepatitis A Hepatitis A is caused by an enterically transmitted RNA virus that, in older children and adults, causes typical symptoms of viral hepatitis, including anorexia, malaise, and jaundice. Young... read more .
For more information, see Hepatitis A Advisory Committee on Immunization Practices Vaccine Recommendations and Centers for Disease Control and Prevention (CDC): Hepatitis A Vaccination. A summary of changes to the 2021 adult immunization schedule is available here.
(See also Overview of Immunization Overview of Immunization Immunity can be achieved Actively by using antigens (eg, vaccines, toxoids) Passively by using antibodies (eg, immune globulins, antitoxins) A toxoid is a bacterial toxin that has been modified... read more .)
Preparations of Hepatitis A Vaccine
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.
Indications for Hepatitis A Vaccine
The HepA vaccine is a routine childhood vaccination (see Table: Recommended Immunization Schedule for Ages 0–6 Years Recommended Immunization Schedule for Ages 0–6 Years Vaccination follows a schedule recommended by the Centers for Disease Control and Prevention (CDC), the American Academy of Pediatrics, the American Academy of Family Physicians, and the American... read more ).
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
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 of Hepatitis A Vaccine
The main contraindication for HepA vaccine is
A severe allergic reaction (eg, anaphylaxis Anaphylaxis Anaphylaxis is an acute, potentially life-threatening, IgE-mediated allergic reaction that occurs in previously sensitized people when they are reexposed to the sensitizing antigen. Symptoms... read more ) 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 of Hepatitis A Vaccine
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 of Hepatitis A Vaccine
No serious adverse effects have been reported.
Mild effects include pain, erythema, swelling, and occasionally induration at the injection site.
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.
Advisory Committee on Immunization Practices (ACIP): Hepatitis A ACIP Vaccine Recommendations
Centers for Disease Control and Prevention (CDC): Hepatitis A Vaccination: Information for Healthcare Providers