Hepatitis B Vaccine Scheduling
All infants should receive the first dose of hepatitis B vaccine within 12 hours of birth before hospital discharge, followed by doses at 1-2 months and 6 months of age. 1
Standard Infant Schedule
The CDC-recommended schedule for all newborns consists of three doses administered at specific intervals: 1, 2, 3
- First dose: Within 12 hours of birth (before hospital discharge)
- Second dose: 1-2 months of age
- Third dose: 6 months of age
The final dose must not be administered before 24 weeks of age, regardless of when earlier doses were given. 2 This timing is critical for optimal long-term immunity.
Infants Born to HBsAg-Positive Mothers
These high-risk infants require immediate intervention: 1, 2
- First dose plus HBIG: Within 12 hours of birth (both administered simultaneously at different sites)
- Second dose: 1-2 months of age
- Third dose: 6 months of age
- Post-vaccination testing: At 9-15 months of age for HBsAg and anti-HBs 4, 1
Delaying the birth dose beyond 12 hours in these infants significantly increases infection risk. 1 Only monovalent hepatitis B vaccine can be used for the birth dose; combination vaccines are acceptable for subsequent doses. 4
Children and Adolescents (Catch-Up Vaccination)
For unvaccinated children and adolescents, the CDC recommends: 1, 3
- Standard 3-dose schedule: 0,1, and 6 months
- Alternative 2-dose schedule (ages 11-15 years only): Adult formulation of Recombivax HB at 0 and 4-6 months 3
Adult Schedule
Adults aged ≥18 years follow a standard 3-dose schedule at 0,1, and 6 months. 1, 2, 3 Alternative schedules producing similar seroprotection include 0,2, and 4 months or 0,1, and 4 months. 2
Accelerated Schedules for Rapid Protection
When rapid protection is needed: 2
- Engerix-B: 0,1,2, and 12 months (4 doses)
- Twinrix (for combined hepatitis A and B protection): 0,7, and 21-30 days, followed by a dose at 12 months 2
Critical Minimum Intervals
These intervals must be strictly observed to ensure adequate immune response: 1, 2, 3
- Between doses 1 and 2: Minimum 4 weeks
- Between doses 2 and 3: Minimum 8 weeks
- Between doses 1 and 3: Minimum 16 weeks
Doses administered ≤4 days before the minimum interval are considered valid ("grace period"). 2, 3 Do not administer the third dose before 16 weeks from the first dose, even if 8 weeks have passed since the second dose. 2
Interrupted Schedules
If the vaccination series is interrupted, do not restart the series—simply continue where you left off. 2, 3 This is a critical point that prevents wasting doses and delaying protection. If interrupted after dose 1, give dose 2 as soon as possible, then dose 3 at least 8 weeks after dose 2. 2
Increasing intervals between doses has little effect on final immunogenicity, and longer intervals between the last 2 doses actually result in higher final antibody levels. 2
Special Populations
Hemodialysis Patients and Immunocompromised Adults
These patients require higher doses and more intensive monitoring: 1, 2, 3
- Dose: 40 μg (double the standard adult dose) using Recombivax HB
- Schedule: 0,1, and 6 months (or 4-dose schedule at 0,1,2, and 6 months with Engerix-B)
- Monitoring: Annual anti-HBs testing with booster doses when levels fall below 10 mIU/mL
Do not use standard adult doses in hemodialysis patients, as they require the higher 40 μg doses. 2
Pregnant Women
Pregnant women should use Engerix-B, Recombivax HB, or Twinrix only. 2 Do not use Heplisav-B or PreHevbrio in pregnant women due to insufficient safety data. 2
Preterm Infants
For infants born to HBsAg-negative mothers weighing ≥2,000 g (4.4 lbs), administer the first dose before hospital discharge. 5 For infants <2,000 g, many guidelines recommend delaying the birth dose until the infant reaches 2,000 g or one month of age, though this varies by jurisdiction. 6
Post-Vaccination Testing
Post-vaccination serologic testing (1-2 months after completing the series) is recommended for: 1
- Infants born to HBsAg-positive mothers
- Healthcare personnel
- Hemodialysis patients
- HIV-infected persons
- Other immunocompromised persons
An anti-HBs level ≥10 mIU/mL indicates adequate protection. 1 After the standard 3-dose series, >90% of healthy adults under 40 years achieve protective antibody response, though response rates decline with age. 2
Immunogenicity Timeline
Understanding the progressive immune response helps explain the schedule rationale: 2
- After dose 1: 30-55% achieve protective antibody levels
- After dose 2: 75% achieve protection
- After dose 3: >90% achieve protection with traditional vaccines
Vaccine-induced immunity persists for >30 years without need for routine boosters in immunocompetent individuals. 2, 7
Common Pitfalls to Avoid
- Never restart the series if interrupted—this wastes doses and delays protection 2, 3
- Do not give the third dose before 16 weeks from the first dose, even if 8 weeks have passed since the second dose 2
- Do not give the final infant dose before 24 weeks of age, as this may compromise long-term immunity 2
- Do not use Twinrix simply for hepatitis B vaccination when the patient has no indication for hepatitis A protection 2
- Do not use Heplisav-B or PreHevbrio in pregnant women, children, or hemodialysis patients 2