What is the recommended post-exposure prophylaxis (PEP) for Hepatitis B (HBV)?

Hepatitis B Post-Exposure Prophylaxis (PEP)

For hepatitis B post-exposure prophylaxis, administer hepatitis B immune globulin (HBIG) plus hepatitis B vaccine series for unvaccinated individuals exposed to HBsAg-positive sources, ideally within 24 hours of exposure. 1

PEP Recommendations Based on Exposure Source and Vaccination Status

When Source is HBsAg-Positive

For Unvaccinated Persons:

• Administer HBIG (0.06 mL/kg IM) as soon as possible, preferably within 24 hours 2
• Initiate hepatitis B vaccine series simultaneously at a separate anatomical site 1
• Complete the full 3-dose vaccine series according to schedule (0,1, and 6 months) 1

For Previously Vaccinated Persons:

• With documented immunity (anti-HBs ≥10 mIU/mL): No PEP needed 1
• With documented non-response to a complete vaccine series: Administer HBIG plus a booster dose of vaccine, or two doses of HBIG (one month apart) 1
• With unknown antibody response: Test for anti-HBs 1
  • If adequate (≥10 mIU/mL): No treatment needed
  • If inadequate (<10 mIU/mL): HBIG plus vaccine booster dose 1

When Source Has Unknown HBsAg Status

For Unvaccinated Persons:

• Initiate hepatitis B vaccine series as soon as possible, preferably within 24 hours 1
• Complete the full vaccine series according to schedule

For Previously Vaccinated Persons:

• With documented immunity: No PEP needed
• With incomplete vaccination: Complete the vaccine series 1

Timing Considerations

The effectiveness of PEP diminishes with time after exposure:

• Initiate PEP as soon as possible after exposure, ideally within 24 hours 2
• PEP is unlikely to be effective beyond 7 days for percutaneous exposures 1
• For sexual exposures, PEP may be effective up to 14 days after exposure 1

Special Exposure Scenarios

Perinatal Exposure

• For infants born to HBsAg-positive mothers:
  • Administer HBIG (0.5 mL) within 12 hours of birth 2
  • Initiate hepatitis B vaccine series within 24 hours of birth 2
  • Complete the vaccine series at 1 and 6 months 2

Sexual Exposure

• For unvaccinated persons exposed to an HBsAg-positive sex partner:
  • Administer HBIG (0.06 mL/kg) within 14 days of last sexual contact 2
  • Initiate hepatitis B vaccine series simultaneously 2

Household Exposure

• For household contacts of persons with acute HBV infection:
  • PEP indicated only for infants <12 months of age or those with identifiable blood exposure 2
  • For infants: HBIG (0.5 mL) plus vaccine series 2

Post-Vaccination Testing

• Postvaccination testing for anti-HBs is recommended 1-2 months after completing the vaccine series for:
  • Persons who received HBIG (test 4-6 months after HBIG administration) 1
  • Healthcare workers 1
  • Infants born to HBsAg-positive mothers 1
  • Immunocompromised persons 3

Common Pitfalls and Caveats

1. Delayed administration: Effectiveness decreases significantly when PEP is delayed. Always prioritize rapid administration, ideally within 24 hours of exposure 2.

2. Incomplete follow-up: Ensure completion of the full vaccine series even if HBIG was administered 1.

3. Failure to test source: When possible, test the source for HBsAg to guide appropriate PEP decisions 1.

4. Misinterpreting vaccination history: Written documentation of complete vaccination is required; verbal history is not sufficient to determine protection 1.

5. Overlooking special populations: Immunocompromised individuals may require modified approaches and definitely need post-vaccination testing 3.

By following these evidence-based guidelines for hepatitis B post-exposure prophylaxis, healthcare providers can effectively prevent HBV infection and its potentially serious long-term consequences in exposed individuals.