Hepatitis B Vaccination Schedule for a Previously Unvaccinated 6-Year-Old
A previously unvaccinated 6-year-old child should receive a 3-dose series of hepatitis B vaccine using the pediatric dose of 10 mcg (0.5 mL) administered at 0,1, and 6 months. 1, 2, 3
Standard Vaccination Schedule
For children aged 6 years (birth through 10 years), the recommended schedule is:
- First dose: At the initial visit (month 0)
- Second dose: 1 month after the first dose
- Third dose: 6 months after the first dose 1, 2, 3
The minimum age for hepatitis B vaccine is birth, and there is no need to restart the vaccine series regardless of time elapsed between doses. 1
Dosing Specifications
The appropriate dose for a 6-year-old is 10 mcg (0.5 mL) for all three doses. 2, 3 This pediatric formulation is used for children from birth through 10 years of age. 3
The vaccine should be administered intramuscularly in the deltoid muscle. 3 A 5/8-inch, 25-gauge needle may be used for children up to and including 10 years of age. 3
Alternative Schedules (When Applicable)
While the 0,1,6-month schedule is standard, an alternative 0,12,24-month schedule is acceptable for children aged 5-10 years who are at low risk of immediate hepatitis B exposure. 1, 4
Research demonstrates that the 0,12,24-month schedule produces excellent immunogenicity, with 88.8% of children achieving seroprotection before the third dose and 98.1% achieving seroprotection one month after completing the series. 4 However, the standard 0,1,6-month schedule produces slightly higher geometric mean titers (5,687 mIU/mL versus 3,159 mIU/mL). 3, 4
For a 6-year-old with no known immediate exposure risk, the extended schedule may be considered for convenience, but the standard 0,1,6-month schedule remains preferred. 2, 4
Expected Immune Response
Approximately 95-100% of healthy children aged 6-10 years achieve protective antibody levels (≥10 mIU/mL) after completing the 3-dose series. 2 In clinical trials with children aged 6 months to 10 years given 10 mcg at months 0,1, and 6, the seroprotection rate was 98% one to two months after the third dose, with a geometric mean titer of 4,023 mIU/mL. 3
Post-Vaccination Testing
Routine post-vaccination serologic testing is NOT recommended for healthy children, even if they are household contacts of HBsAg-positive individuals. 2 Post-vaccination testing is reserved only for specific high-risk groups including infants born to HBsAg-positive mothers, healthcare personnel, hemodialysis patients, HIV-infected persons, and other immunocompromised individuals. 2
Special Considerations for High-Risk Exposure
If the child is a household contact of an HBsAg-positive individual, vaccination should still follow the standard 0,1,6-month schedule without hepatitis B immune globulin (HBIG). 2 HBIG is only indicated for newborns of HBsAg-positive mothers within 12 hours of birth or for specific post-exposure scenarios, not for routine household contact vaccination. 1, 2
For children with known or presumed recent exposure to hepatitis B virus, an accelerated 0,1,2-month schedule with a fourth dose at 12 months may be considered, along with HBIG if appropriate. 1, 3 This accelerated schedule produces 96% seroprotection by month 4. 1, 3
Critical Timing Considerations
The third dose should not be administered before 24 weeks (164 days) of age for any child, regardless of when the series was started. 1 However, since this child is 6 years old, this constraint is not relevant.
The minimum interval between the first and second doses is 4 weeks, and the minimum interval between the second and third doses is 8 weeks (and 16 weeks after the first dose). 1
Common Pitfalls to Avoid
Do not delay vaccination. The child should begin the series at the next available visit, having already missed the recommended infant/early childhood immunization window. 2
Do not administer HBIG for routine household contact vaccination. HBIG is not indicated unless there is acute exposure or the child is a newborn of an HBsAg-positive mother. 2
Do not restart the series if doses are delayed. Simply continue with the next dose regardless of the time elapsed. 1
Do not use combination vaccines containing hepatitis B (such as Pediarix) for catch-up vaccination in a 6-year-old, as these are typically designed for the infant schedule. Use monovalent hepatitis B vaccine. 1
Duration of Protection
Vaccine-induced immunity persists for at least 10-30 years in immunocompetent individuals who achieve adequate initial antibody response, and booster doses are not routinely recommended. 2 The magnitude of the initial antibody response predicts long-term antibody persistence, with higher peak titers associated with longer duration of protection. 1, 2