What is the recommended regimen and administration guidelines for the Hepatitis B (Hep B) vaccine in adults and children?

Hepatitis B Vaccine: Recommended Regimens and Administration Guidelines

All adults aged 19-59 years should receive hepatitis B vaccination universally, while adults ≥60 years with risk factors should be vaccinated, and those ≥60 without risk factors may receive vaccination. 1

Universal Vaccination Recommendations by Age Group

Infants and Children

• All medically stable infants weighing ≥2,000 grams born to HBsAg-negative mothers must receive the first dose within 24 hours of birth 1
• Infants <2,000 grams should delay the first dose until hospital discharge or age 1 month 1
• The final dose must not be administered before age 24 weeks (164 days) 1
• All unvaccinated children and adolescents aged <19 years require catch-up vaccination 1

Adults (19-59 Years)

• Universal vaccination is now recommended for all adults aged 19-59 years, eliminating the need for risk assessment 1
• This represents a major shift from previous risk-based recommendations and addresses the reality that risk assessment has been ineffective in clinical practice 1

Adults ≥60 Years

• Adults ≥60 years with risk factors should receive vaccination 1
• Adults ≥60 years without known risk factors may receive vaccination (permissive recommendation shifting responsibility to providers to offer, not wait for patient request) 1

Standard Vaccine Schedules and Formulations

Three-Dose Series (Engerix-B, Recombivax HB)

• Standard schedule: 0,1, and 6 months 1
• Adolescents aged 11-19 years: 10 μg at 0,1, and 6 months 1
• Adults ≥20 years: Recombivax HB 10 μg (1.0 mL) or Engerix-B 20 μg (1.0 mL) 1
• Alternative schedule for high-risk populations: 0,1,2, and 12 months provides optimal early seroconversion and long-term protection 2

Two-Dose Series (Heplisav-B)

• Adults ≥18 years: Two doses separated by 1 month 1
• Heplisav-B is contraindicated in infants, children, and adolescents <18 years 1
• Offers improved compliance due to shorter schedule 3

Combination Vaccine (Twinrix)

• Standard schedule: 0,1, and 6 months for adults ≥18 years 1
• Accelerated schedule: 0,7,21-30 days, plus booster at 12 months 4, 5
• The 12-month booster dose is essential for long-term immunity 5

Special Populations Requiring Modified Dosing

Hemodialysis patients and immunocompromised persons ≥20 years:

• Recombivax HB: 40 μg (dialysis formulation) at 0,1, and 6 months 1
• Engerix-B: Two 1.0-mL doses (40 μg total) administered at one site on a 4-dose schedule at 0,1,2, and 6 months 1
• Require annual anti-HBs monitoring 1

Critical Timing Principles for Interrupted Schedules

If any dose is delayed, never restart the series—simply administer the delayed dose as soon as possible 1, 5, 6

Minimum Intervals Between Doses

• Second dose: At least 4 weeks after the first dose 5, 6
• Third dose: At least 8 weeks after the second dose AND at least 16 weeks after the first dose 5, 6
• A 4-day grace period is acceptable for all intervals except the Twinrix accelerated schedule 5

Twinrix-Specific Timing

• If day 21 is missed on the accelerated schedule, administer within the 21-30 day window 4
• If the entire window is missed, give immediately when patient returns 4
• The 12-month dose should be given 12 months after the first dose, not adjusted based on third dose timing 4

High-Risk Groups Requiring Urgent Vaccination

Sexual Exposure Risk

• Sex partners of HBsAg-positive persons 1
• Sexually active persons not in long-term mutually monogamous relationships 1
• Persons seeking evaluation or treatment for sexually transmitted infections 1
• Men who have sex with men 1

Percutaneous/Mucosal Blood Exposure Risk

• Healthcare personnel and public safety workers with potential blood/body fluid exposure 1, 5
• Injection drug users 1
• Hemodialysis and end-stage renal disease patients 1

Other High-Risk Categories

• Household contacts of HBsAg-positive persons 1
• HIV-infected persons 1
• Persons born in countries with HBV endemicity ≥2% 5, 7
• Incarcerated persons 1
• Persons with chronic liver disease 1
• Persons with diabetes aged <60 years 1

Prevaccination and Postvaccination Testing

When to Consider Prevaccination Testing

• Prevaccination serologic testing can be considered in populations with expected high prevalence (20-30%) of HBV infection to identify chronic infection and reduce costs 1
• Recommended for unvaccinated household, sexual, and needle-sharing contacts of HBsAg-positive persons 1
• Testing should never delay vaccination—administer the first dose immediately after blood collection 1

Postvaccination Serologic Testing Requirements

• Measure anti-HBs levels 1-2 months after completing the series for high-risk groups: 1, 5, 8
  • Healthcare personnel with blood exposure risk
  • Hemodialysis patients
  • HIV-infected persons
  • Other immunocompromised individuals
  • Infants born to HBsAg-positive mothers
• Seroprotection is defined as anti-HBs ≥10 mIU/mL 5, 9
• Routine postvaccination testing is unnecessary for immunocompetent persons 1

Management of Non-Responders

• If anti-HBs <10 mIU/mL after the first series, administer a second 3-dose series 1
• Consider high-dose formulation (40 μg) for adolescents and adults 1
• Alternative: Administer one dose and retest anti-HBs 1
• For persistent non-responders, consider Heplisav-B or adjuvants like GM-CSF 6, 9

Special Populations and Circumstances

Pregnant Women

• Pregnant women at risk for HBV infection during pregnancy should be vaccinated 1
• Risk factors include: >1 sex partner in previous 6 months, STI evaluation/treatment, injection drug use, or HBsAg-positive sex partner 1
• All pregnant women must be tested for HBsAg during each pregnancy 1
• Women with HBV DNA >10⁶ IU/mL at 26-28 weeks gestation should receive antiviral therapy (tenofovir, telbivudine, or lamivudine) through 4 weeks postpartum 1

Solid Organ Transplant Candidates

• Should receive all age-appropriate vaccines based on CDC schedule 1
• Anti-HBs-negative candidates should receive the vaccine series, with high-dose (40 μg) for those ≥20 years on hemodialysis 1
• If anti-HBs <10 mIU/mL after first series, administer second 3-dose series using standard or high dose 1

Hematopoietic Stem Cell Transplant Recipients

• Administer three doses of HepB vaccine 6-12 months after HSCT 1
• If anti-HBs <10 mIU/mL, give second 3-dose series using high dose (40 μg) 1
• Do not administer live vaccines to patients with active GVHD or ongoing immunosuppression 1

Implementation in High-Risk Settings

In settings where a high proportion of persons have risk factors (STD clinics, correctional facilities, substance abuse treatment centers, facilities serving MSM), assume all adults are at risk and offer universal vaccination 1

Delivery Hospital Requirements

• Implement standing orders and electronic medical record prompts for birth dose administration 1
• Ensure identification of infants born to HBsAg-positive mothers or mothers with unknown status 1
• Establish policies for timely prophylaxis initiation 1

Case Management Programs

• States should establish programs to ensure all pregnant women are tested for HBsAg 1
• HBsAg-positive women should be tested for HBV DNA to guide maternal antiviral therapy 1
• Infants born to HBsAg-positive or unknown-status mothers require case management 1

Safety and Contraindications

Safety Profile

• Pain at injection site and low-grade fever reported by a minority of recipients 1
• Anaphylaxis occurs in approximately 1 per 1.1 million doses 1
• No deaths have been reported from vaccine-related anaphylaxis 1

Contraindications

• History of anaphylaxis after previous hepatitis B vaccine dose 1
• Known anaphylactic reaction to any vaccine component 1
• No other adverse events have been demonstrated 1

Common Pitfalls to Avoid

• Do not restart the series for any reason when doses are delayed—this wastes vaccine and delays protection 1, 5, 6
• Do not delay vaccination while conducting risk assessment—universal vaccination eliminates this barrier 1
• Do not accept patient self-report as evidence of vaccination—only dated written records are acceptable 1
• Do not administer the final dose before age 24 weeks in infants 1
• Do not give doses at intervals shorter than minimum requirements—these must be readministered 5, 6
• Do not skip postvaccination testing in high-risk groups (healthcare workers, hemodialysis patients, immunocompromised) 5, 8