Hepatitis B Vaccine Regimens
For adults aged 19-59 years, the Advisory Committee on Immunization Practices now recommends universal hepatitis B vaccination using either a 3-dose series (Recombivax HB, Engerix-B, or PreHevbrio at 0,1, and 6 months) or a 2-dose series (Heplisav-B at 0 and 1 month), while infants should receive their first dose within 24 hours of birth followed by doses at 1-2 months and 6 months, with the final dose not administered before 24 weeks of age. 1, 2
Adult Vaccination (≥18 Years)
Standard Regimens
Three-dose schedules:
- Recombivax HB: 10 μg (1.0 mL) at 0,1, and 6 months for adults ≥20 years 1, 3
- Engerix-B: 20 μg (1.0 mL) at 0,1, and 6 months for adults ≥20 years 1, 3
- PreHevbrio: 10 μg (1.0 mL) at 0,1, and 6 months for adults ≥18 years 1, 3
Two-dose schedule:
- Heplisav-B: 20 μg (0.5 mL) at 0 and 1 month for adults ≥18 years, achieving approximately 90% seroprotection compared to 70.5-90.2% with Engerix-B 1, 2
Alternative Schedules
The 3-dose vaccines can be administered on flexible schedules at 0,1, and 4 months or 0,2, and 4 months with similar seroprotection rates, though longer intervals between the last two doses produce higher final antibody titers 2. For rapid protection, Twinrix (combined hepatitis A and B vaccine) can be given on an accelerated schedule at days 0,7, and 21-30, followed by a booster at 12 months 1, 2.
Universal Adult Vaccination Expansion
All adults aged 19-59 years should now receive hepatitis B vaccination regardless of risk factors, removing the need for risk factor screening and disclosure 1. Adults ≥60 years without known risk factors may receive the vaccine 1.
Infant Vaccination
Standard Infant Schedule
The first dose must be administered within 24 hours of birth (preferably within 12 hours), followed by doses at 1-2 months and 6 months 2, 4. The final dose must not be given before 24 weeks of age, as earlier administration may compromise long-term immunity 2.
High-Risk Infants (Born to HBsAg-Positive Mothers)
These infants require both hepatitis B vaccine AND hepatitis B immune globulin (HBIG) 0.5 mL administered within 12 hours of birth 2, 4. The vaccine series follows at 0-7 days, 1-2 months, and 6 months 4. Delaying the birth dose beyond 12 hours significantly increases infection risk 2. Post-vaccination testing for HBsAg and anti-HBs should occur at 9-15 months of age 2.
Special Populations
Hemodialysis and Immunocompromised Adults
These patients require higher doses:
- Recombivax HB: 40 μg (1.0 mL) at 0,1, and 6 months 1, 3
- Engerix-B: 40 μg (2.0 mL) in a 4-dose schedule at 0,1,2, and 6 months 1, 3
Annual anti-HBs testing is recommended with booster doses when levels fall below 10 mIU/mL 2. Do not use Heplisav-B or PreHevbrio in hemodialysis patients, as safety and effectiveness have not been established in this population 1, 3.
Pregnant Women
Use only Engerix-B, Recombivax HB, or Twinrix in pregnant women 1, 2. Heplisav-B and PreHevbrio have insufficient data on vaccine-associated risks in pregnancy and should be avoided 1, 3.
Adolescents (11-19 Years)
- Ages 11-15: Recombivax HB 10 μg (0.5 mL) can be given as either a 2-dose schedule at 0 and 4-6 months OR a standard 3-dose schedule at 0,1, and 6 months 1, 3
- Ages 11-19: Engerix-B 10 μg (0.5 mL) at 0,1, and 6 months 1, 3
Critical Dosing Intervals and Interrupted Schedules
Minimum Intervals
The minimum interval between doses 1 and 2 is 4 weeks, between doses 2 and 3 is 8 weeks, and between doses 1 and 3 is 16 weeks 1, 2. Doses given ≤4 days before the minimum interval are considered valid 1, 2.
Managing Interrupted Schedules
If the vaccination series is interrupted, never restart the series—simply continue where you left off 1, 2, 3. If interrupted after dose 1, give dose 2 as soon as possible, then dose 3 at least 8 weeks after dose 2 2. The final dose of a 3-dose series must be administered ≥8 weeks after the second dose and ≥16 weeks after the first dose 1.
Immunogenicity and Response Rates
After the first dose, 30-55% of adults achieve protective antibody levels (anti-HBs ≥10 mIU/mL), 75% after the second dose, and >90% after the third dose with traditional vaccines 1, 2. Vaccine-induced immunity persists for >30 years 1, 2. Age is a significant factor, with response rates declining in adults over 40 years 5.
Prevaccination and Postvaccination Testing
Prevaccination testing for HBsAg, anti-HBs, and anti-HBc can identify those already immune, but lack of access to testing should never be a barrier to vaccination 1. Testing is not required before vaccination, and in settings where testing is not feasible, vaccination should proceed 1.
Common Pitfalls to Avoid
- Never restart an interrupted series—this wastes doses and delays protection 1, 2, 3
- Never give the third dose before 16 weeks from the first dose, even if 8 weeks have passed since the second dose 1, 2
- Never give the final infant dose before 24 weeks of age, as this may compromise long-term immunity 2
- Never use standard adult doses in hemodialysis patients—they require 40 μg doses 1, 2, 3
- Never use Heplisav-B or PreHevbrio in pregnant women, children, or hemodialysis patients 1, 3
- Never use Twinrix when only hepatitis B protection is needed—reserve it for patients requiring both hepatitis A and B protection 2