What is the recommended Hepatitis A vaccine schedule for pediatric patients?

Hepatitis A Vaccine Schedule for Pediatric Patients

All children in the United States should receive hepatitis A vaccine starting at 12-23 months of age as a 2-dose series, with the second dose administered 6-18 months after the first dose. 1

Primary Vaccination Schedule

Age of Initiation

• Begin the hepatitis A vaccine series at 12-23 months of age (minimum age: 12 months) 1
• The vaccine should be integrated into routine childhood immunization visits 1

Two-Dose Regimen

The specific timing depends on which vaccine formulation is used:

Havrix (GlaxoSmithKline):

• First dose: 0.5 mL (720 ELU) intramuscularly at 12-23 months 1
• Second dose: 6-12 months after the first dose 1

Vaqta (Merck):

• First dose: 0.5 mL (25 U) intramuscularly at 12-23 months 1
• Second dose: 6-18 months after the first dose 1

Important Administration Details

• Both doses should be administered at least 6 months apart for optimal immunogenicity 1
• The two vaccines (Havrix and Vaqta) are interchangeable, though using the same product for both doses is preferable 1
• If the immunization schedule is interrupted, do not restart the series—simply administer the remaining required dose 1

Catch-Up Vaccination

Children 2-18 Years

• Unimmunized children and adolescents aged 2-18 years can begin the hepatitis A vaccination series during any visit 1
• Catch-up vaccination should be especially considered in areas with increasing incidence or ongoing outbreaks 1
• The same 2-dose schedule applies (doses at least 6 months apart) 1

Special Populations Requiring Vaccination

High-Risk Groups

Beyond routine childhood vaccination, hepatitis A vaccine is specifically recommended for: 1

• International travelers: Children traveling to areas with intermediate or high hepatitis A endemicity should be vaccinated before departure 1

  • Protection is reliably present by 4 weeks after the first dose 1
  • May provide protection as early as 2 weeks after immunization 1

• Adolescent males who have sex with men 1

• Users of injectable or non-injectable illicit drugs 1

• Recipients of clotting factors (though risk has been greatly reduced with modern preparation practices) 1

• Laboratory workers exposed to hepatitis A virus 1

Immunocompromised Children

• Immunocompromising conditions are not a contraindication to hepatitis A vaccine 1
• The vaccine is an inactivated preparation and has not shown increased safety risks in children with primary or secondary immunodeficiencies 1

Contraindications

The only contraindication is hypersensitivity to vaccine components, including: 1

• Aluminum hydroxide
• Phenoxyethanol

Storage and Handling

• Store and ship between 2-8°C (36-46°F) 1
• Never freeze the vaccine, as freezing destroys vaccine potency 1
• The vaccine maintains immunogenicity and reactogenicity even if stored at up to 37°C (98°F) for up to 1 week 1

Clinical Pearls and Pitfalls

Common Pitfalls to Avoid

• Do not delay the first dose beyond 23 months of age—this is the optimal window for routine vaccination 1
• Do not require preimmunization serologic testing in adolescents or young adults, as it is not cost-effective 1
• Do not restart the series if the schedule is interrupted; simply complete with the remaining dose 1

Administration Technique

• Administer intramuscularly with needle length appropriate for the child's age and size 1
• The vaccine should appear as a slightly opaque, white-colored suspension when well mixed 1
• Shake the vaccine before administration 1

Alternative Formulation

Twinrix (combined hepatitis A and B vaccine) is available but requires a 3-dose series (0,1, and 6 months) and is typically reserved for specific situations where both hepatitis A and B protection is needed 1