Hepatitis A

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Pregnancy: Safe if indicated.

Hepatitis A vaccine is an inactivated vaccine and is considered safe during pregnancy when the risk of hepatitis A infection warrants vaccination.

• WHO and CDC do not list pregnancy as a contraindication for inactivated hepatitis A vaccine.

• Recommended for pregnant travelers to areas with intermediate/high HAV endemicity.

• Hepatitis A infection during pregnancy carries significant maternal morbidity and risk of preterm delivery.

• No teratogenic effects have been observed in post-marketing surveillance.

• Immune response may be slightly reduced during pregnancy.

Breastfeeding: Safe — no special precautions.

Hepatitis A vaccine (inactivated) is safe during breastfeeding. The vaccine does not contain live virus and poses no risk to the breastfed infant. No modifications to the vaccination schedule or breastfeeding are required.

Pediatric use:

• Licensed from 12 months of age (most formulations).

• Pediatric dose: 0.5 mL IM (half the adult dose for monovalent vaccines).

• Two-dose schedule: 0 and 6–18 months.

• Children <12 months: not routinely recommended (maternal antibodies may interfere), but can be given from 6 months for travel; a repeat 2-dose series is then needed from 12 months.

• Seroconversion rates: virtually 100% after 2 doses in healthy children.

• Combined Hep A/B vaccines (e.g., Twinrix Junior) available for children ≥1 year.

Geriatric use:

• Immune response may be reduced in older adults (≥60 years), but protective antibody levels are still achieved in >95% of vaccinees after 2 doses.

• Hepatitis A infection tends to be more severe in older adults and those with underlying liver disease — vaccination is particularly beneficial.

• No dose adjustment required. Standard 2-dose schedule applies.

• Adverse event profile is similar to younger adults.