Hepatitis B Vaccine for Prophylaxis
For hepatitis B prophylaxis, use single-antigen hepatitis B vaccine (such as Engerix-B or Recombivax HB) administered in a 3-dose series at 0,1, and 6 months for most populations, or Heplisav-B as a 2-dose series at 0 and 1 month for adults. 1, 2
Vaccine Selection by Clinical Context
Standard Prophylaxis for Most Populations
- Single-antigen hepatitis B vaccines (Engerix-B, Recombivax HB, or Heplisav-B) are the recommended vaccines for hepatitis B prophylaxis. 1, 2
- The standard 3-dose schedule (0,1, and 6 months) achieves >90% seroprotection in adults under 40 years of age after series completion. 2, 3
- Heplisav-B offers superior immunogenicity with approximately 90% seroprotection compared to 70.5-90.2% with Engerix-B, and requires only 2 doses (0 and 1 month). 2, 4
Post-Exposure Prophylaxis (High-Risk Situations)
- For infants born to HBsAg-positive mothers, administer single-antigen hepatitis B vaccine PLUS hepatitis B immune globulin (HBIG) within 12 hours of birth at separate injection sites. 1
- Only single-antigen HepB vaccine should be used for the birth dose; combination vaccines are not appropriate. 1
- Delaying the birth dose beyond 12 hours significantly increases infection risk in this population. 2
When to Use Twinrix (Combined Hepatitis A and B Vaccine)
- Reserve Twinrix for patients who require protection against BOTH hepatitis A and hepatitis B viruses. 2
- Appropriate populations include international travelers to endemic regions, men who have sex with men at risk for both infections, and persons with chronic liver disease needing both vaccines. 2
- Do not use Twinrix simply for hepatitis B prophylaxis when the patient has no indication for hepatitis A protection, as this exposes patients to unnecessary hepatitis A antigen. 2
- Twinrix is administered as 3 doses at 0,1, and 6 months, or as an accelerated 4-dose schedule at days 0,7,21-30, and 12 months for rapid protection. 2
Dosing Schedules by Population
Infants and Children
- Infants (standard): 3-dose series at 0,1-2, and 6 months using 10 mcg Engerix-B or 5 mcg Recombivax HB. 1, 3
- Infants born to HBsAg-positive mothers: Birth dose within 12 hours plus HBIG, then at 1-2 months and 6 months; final dose must not be given before 24 weeks of age. 1
- For infants weighing <2,000 grams born to HBsAg-positive mothers, the birth dose should not count toward the series; give 3 additional doses (total 4 doses) starting at 1 month of age. 1
- Children aged 6 months to 10 years: 10 mcg Engerix-B at 0,1, and 6 months achieves 98% seroprotection. 3
Adolescents and Adults
- Standard adult dose: 20 mcg Engerix-B or 10 mcg Recombivax HB at 0,1, and 6 months. 2, 3
- Alternative: Heplisav-B 20 mcg at 0 and 1 month (2-dose series only). 2, 4
- Alternative schedules of 0,2, and 4 months or 0,1, and 4 months produce similar seroprotection rates. 2
Special Populations Requiring Higher Doses
- Hemodialysis patients and immunocompromised adults: 40 mcg Recombivax HB (or 2 × 20 mcg Engerix-B) at 0,1,2, and 6 months (4-dose series). 2, 3
- This achieves 67% seroprotection compared to approximately 50% with standard dosing. 3
- Annual anti-HBs testing is recommended with booster doses when levels fall below 10 mIU/mL. 2
Vaccine Non-Responders
- For adults who failed conventional vaccination, use high-dose revaccination with 40 mcg Engerix-B at 0,1,2, and 6 months. 4
- Alternatively, use Heplisav-B (if available) as a 2-dose series, which demonstrates higher seroprotection rates in non-responders. 4
- Test anti-HBs levels 1-2 months after completing revaccination to confirm seroprotection (≥10 mIU/mL). 4
Critical Timing and Interval Requirements
Minimum Intervals Between Doses
- Minimum interval between doses 1 and 2: 4 weeks. 2
- Minimum interval between doses 2 and 3: 8 weeks. 2
- Minimum interval between doses 1 and 3: 16 weeks. 2
- Doses given ≤4 days before the minimum interval are considered valid. 2, 4
Special Timing Considerations
- The final dose in the infant series must not be administered before 24 weeks (164 days) of age, regardless of when earlier doses were given. 1, 2
- For infants born to HBsAg-positive mothers, the final dose should not be given before 24 weeks to ensure adequate long-term immunity. 1
Important Clinical Pitfalls to Avoid
Common Errors in Vaccine Administration
- Never restart the vaccine series if interrupted—simply continue where you left off. 2, 4
- 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 use standard adult doses in hemodialysis patients; they require 40 mcg doses. 2, 3
- Do not use Heplisav-B or PreHevbrio in pregnant women, children, or hemodialysis patients due to insufficient safety data. 2
Post-Vaccination Testing
- For infants born to HBsAg-positive mothers: Test for anti-HBs and HBsAg at 9-12 months of age (after series completion). 1
- Testing should not be performed before 9 months to avoid detecting passive anti-HBs from HBIG administered at birth. 1
- For high-risk adults (healthcare personnel, hemodialysis patients, immunocompromised individuals), test anti-HBs 1-2 months after final dose to confirm seroprotection ≥10 mIU/mL. 2, 4
Age-Related Considerations
- Older adults (>40 years) have lower seroconversion rates and lower antibody titers than younger adults. 4, 3
- Among adults over 40 years given standard dosing, the GMT is significantly lower (610 mIU/mL) compared to younger adults. 3
- Consider high-dose regimens or Heplisav-B for older adults to overcome age-related immune senescence. 4
Pregnancy Considerations
- Pregnant women should use Engerix-B, Recombivax HB, or Twinrix only. 2
- Do not use Heplisav-B or PreHevbrio in pregnancy due to insufficient safety data. 2