What are the indications, recommended schedule, dosing, and post‑vaccination serology for hepatitis B vaccine in infants, adolescents, adults, and high‑risk groups?

Hepatitis B Vaccine: Indications, Schedules, Dosing, and Post-Vaccination Serology

All infants should receive hepatitis B vaccine starting at birth, all children and adolescents aged <19 years who are unvaccinated should receive catch-up vaccination, and all adults aged 19–59 years should receive universal vaccination regardless of risk factors. 1

Universal Infant Vaccination

For all medically stable infants weighing ≥2,000 grams born to HBsAg-negative mothers, administer the first dose within 24 hours of birth before hospital discharge. 1

• Infants weighing <2,000 grams born to HBsAg-negative mothers should delay the first dose until hospital discharge or age 1 month, even if weight remains <2,000 grams. 1
• Complete the series with either single-antigen vaccine or combination vaccine at 0,1–2, and 6 months (final dose not before 24 weeks of age). 1
• A 4-dose series is permissible when combination vaccines are used after the birth dose. 1
• In high-risk populations (Alaska Natives, Pacific Islanders, immigrants from endemic regions), administer the first dose at birth and the final dose at 6–12 months. 1

Infants Born to HBsAg-Positive Mothers

Administer hepatitis B vaccine AND hepatitis B immune globulin (HBIG) within 12 hours of birth, regardless of birth weight. 1, 2

• Use the 0,1,6-month schedule or the accelerated 0,1,2,12-month schedule. 2
• Test for HBsAg and anti-HBs at 9–12 months of age (1–2 months after series completion). 1
• For infants with anti-HBs <10 mIU/mL after the primary series, give one 10 µg dose and retest 1–2 months later; if still <10 mIU/mL, administer two additional doses to complete a second series. 3

Children and Adolescent Catch-Up Vaccination

All unvaccinated children and adolescents aged <19 years should receive hepatitis B vaccine at any age. 1

Standard Dosing for Children and Adolescents

• Ages 0–10 years: 10 µg (0.5 mL) per dose at 0,1,6 months. 4, 2
• Ages 11–19 years: 10 µg (0.5 mL) per dose at 0,1,6 months OR 20 µg (1.0 mL) per dose at 0,1,6 months. 4, 2
• Alternative for ages 11–15 years (Recombivax HB only): 10 µg (0.5 mL) in a 2-dose schedule at 0 and 4–6 months. 4

Implementation Strategies

• Review immunization records at age 11–12 years and complete the series if incompletely vaccinated. 1
• Prioritize children from Asia, Pacific Islands, Africa, or other endemic regions for record review and series completion. 1
• Initiate vaccination even if series completion cannot be ensured; do not delay the first dose. 1

Adult Vaccination (Ages ≥19 Years)

Universal hepatitis B vaccination is recommended for all adults aged 19–59 years without requiring acknowledgment of specific risk factors. 1, 5

Standard Adult Dosing Options

• Heplisav-B: 20 µg (0.5 mL) at 0 and 1 month (2-dose series, approximately 90% seroprotection). 5, 4
• Engerix-B: 20 µg (1.0 mL) at 0,1, and 6 months (3-dose series). 5, 4, 2
• Recombivax HB: 10 µg (1.0 mL) at 0,1, and 6 months (3-dose series). 5, 4
• PreHevbrio: 10 µg (1.0 mL) at 0,1, and 6 months (3-dose series). 5, 4

Accelerated Schedules When Rapid Protection Is Needed

• Standard accelerated: 0,1,2,12 months (the fourth dose at 12 months is essential for long-term immunity). 5, 4
• Twinrix (combined hepatitis A/B): Standard schedule at 0,1,6 months OR super-accelerated at 0 days, 7 days, 21–30 days, and 12 months. 5, 4, 6
• The usual 4-day grace period does not apply to the first three doses of Twinrix super-accelerated schedule; strict adherence to timing is required. 5, 4

High-Risk Groups Requiring Vaccination

Healthcare workers, public-safety workers with blood exposure, clients and staff of institutions for the developmentally disabled, hemodialysis patients, HIV-infected persons, persons with chronic liver disease, household contacts and sex partners of HBsAg-positive individuals, injection drug users, and persons with multiple sex partners should receive hepatitis B vaccine. 1

Special Population Dosing

Hemodialysis patients and immunocompromised adults ≥20 years:

• Recombivax HB: 40 µg (1.0 mL) per dose at 0,1,6 months. 5, 4, 2
• Engerix-B: 40 µg (2.0 mL) per dose at 0,1,2,6 months (administered as two 20 µg injections). 5, 4, 2
• Do not use Heplisav-B or PreHevbrio in hemodialysis patients due to insufficient safety and efficacy data. 5, 4

Pregnant women:

• Use only Engerix-B, Recombivax HB, or Twinrix; Heplisav-B and PreHevbrio are contraindicated due to lack of pregnancy safety data. 5, 4
• Vaccinate pregnant women at risk for HBV infection during pregnancy (multiple sex partners, STI evaluation/treatment, injection drug use, HBsAg-positive sex partner). 1

Schedule Intervals and Interrupted Series

Minimum Interval Requirements

• Dose 1 → Dose 2: ≥4 weeks. 5, 4
• Dose 2 → Dose 3: ≥8 weeks. 5, 4
• Dose 1 → Dose 3: ≥16 weeks. 5, 4
• Doses given ≤4 days before the minimum interval are considered valid. 5, 4

Managing Interrupted Series

Never restart an interrupted hepatitis B vaccine series regardless of time elapsed; simply continue from where it was stopped. 5, 4

• There is no maximum interval between doses. 5, 4
• If interrupted after the first dose, give the second dose as soon as possible, then separate doses 2 and 3 by ≥8 weeks. 5, 4
• Switching vaccine brands within a series is permissible and does not require restarting. 4

Post-Vaccination Serologic Testing

Populations Requiring Anti-HBs Testing

Mandatory testing 1–2 months after series completion for:

• Healthcare personnel and public-safety workers with blood-exposure risk. 5, 4
• Hemodialysis patients. 5, 4
• HIV-infected persons and other immunocompromised individuals. 5, 4
• Sex partners of HBsAg-positive individuals. 5
• Infants born to HBsAg-positive mothers. 5, 3

Protective anti-HBs level is defined as ≥10 mIU/mL. 5, 4, 3

No Routine Testing Required

• Routine post-vaccination serologic testing is not necessary for most healthy adults, children, and adolescents. 5, 4
• Pre-vaccination testing is not required and should never delay vaccination. 5, 4

Revaccination and Booster Doses

Immunocompetent Persons

Routine booster doses are not recommended for individuals with normal immune status who completed the primary series, even if anti-HBs declines below 10 mIU/mL. 3

• Immunologic memory provides long-term protection despite declining antibody levels. 3

Healthcare Personnel Non-Responders

For HCP with anti-HBs <10 mIU/mL after a complete series, give one additional 20 µg dose and retest 1–2 months later. 3

• If anti-HBs remains <10 mIU/mL, administer a second full 3-dose series (total of six doses) and retest 1–2 months after the final dose. 3
• Individuals who fail to achieve ≥10 mIU/mL after two complete series should not receive additional vaccine; instead, provide HBIG for known HBsAg-positive exposures. 3

Hemodialysis Patients

Perform annual anti-HBs testing; when levels drop below 10 mIU/mL, give a 40 µg booster dose. 3, 2

Other Immunocompromised Persons

• Revaccinate when anti-HBs <10 mIU/mL with three additional doses at 0,1,6 months, testing 1–2 months after the final dose. 3

Critical Pitfalls to Avoid

• Never restart an interrupted series—this wastes doses and delays immunity. 5, 4
• Do not administer the third dose before 16 weeks from the first dose, even if 8 weeks have passed since the second dose. 5
• Standard adult doses are inappropriate for hemodialysis patients—use 40 µg formulations. 5, 4
• Avoid Heplisav-B and PreHevbrio in pregnant women, hemodialysis patients, and children due to insufficient safety data. 5, 4
• Do not delay vaccination for serologic testing—lack of testing should never be a barrier. 5, 4
• After age 40 years, vaccine response declines to approximately 75% seroprotection by age 60 years; consider this when counseling older adults. 5