What are the recommendations for someone with a negative and low Hepatitis B (HB) antibody test result?

Management of Negative and Low Hepatitis B Antibody Results

Individuals with negative or low hepatitis B antibody (anti-HBs) levels (<10 mIU/mL) should receive revaccination with a complete hepatitis B vaccine series followed by post-vaccination testing 1-2 months after the final dose. 1

Understanding Anti-HBs Levels and Protection

• Anti-HBs levels ≥10 mIU/mL are considered protective against hepatitis B virus (HBV) infection 1
• Levels <10 mIU/mL after a complete vaccination series indicate inadequate protection and require revaccination 1
• Most non-responders (44-100%) will develop protective antibody levels after receiving a second complete three-dose vaccination series 1

Recommendations Based on Risk Category

For General Population:

• Immunocompetent individuals with anti-HBs <10 mIU/mL after primary vaccination should receive a complete revaccination series 1
• After revaccination, test anti-HBs levels 1-2 months after the final dose to confirm response 1
• If still no response after revaccination, test for HBsAg to rule out chronic infection 1

For High-Risk Groups:

• Healthcare workers, dialysis patients, immunocompromised individuals, and sexual partners of HBsAg-positive persons require post-vaccination testing 1-2 months after completing the vaccination series 1
• Dialysis patients and immunocompromised individuals with anti-HBs <10 mIU/mL need booster doses and annual testing 1
• HIV-infected persons and other immunocompromised individuals may require more frequent monitoring of anti-HBs levels 1

Revaccination Protocol

1. For most individuals: Administer a complete 3-dose series (at 0,1, and 6 months) 1
2. For infants born to HBsAg-positive mothers with anti-HBs <10 mIU/mL: Give a single dose of HepB vaccine and retest 1-2 months later; if still <10 mIU/mL, complete the second series with two additional doses 1
3. For healthcare workers with documented complete vaccination but anti-HBs <10 mIU/mL: Provide one additional dose followed by testing; if still <10 mIU/mL, complete with two more doses 1

Special Considerations

• Despite anti-HBs levels falling below 10 mIU/mL over time, most immunocompetent individuals maintain immune memory and do not require booster doses 1, 2
• Some studies suggest that anti-HBs levels ≥2 IU/L may be sufficient to prompt an anamnestic response upon exposure 3
• Persons exposed to HBV who have anti-HBs <10 mIU/mL should receive hepatitis B immune globulin (HBIG, 0.06 mL/kg) and hepatitis B vaccine as soon as possible, preferably within 24 hours 1

Common Pitfalls to Avoid

• Do not assume that undetectable anti-HBs always means lack of immunity, as cellular immune memory may persist despite antibody levels below detection 2, 4
• Do not delay post-vaccination testing beyond 1-2 months after the final dose, as this is the optimal time to assess response 1
• Do not forget to test for HBsAg in non-responders to rule out chronic HBV infection 1
• Do not use anti-HBc as the only screening test for HBV immunity, as it cannot distinguish between immunity from vaccination versus past infection 5

Prevention of HBV Transmission

• Sexual partners of HBV carriers should be vaccinated if they test negative for HBV serologic markers 1
• Barrier protection methods should be used for sexual partners who have not been tested or have not completed the full immunization series 1
• Household contacts of HBV carriers should be tested and vaccinated if negative for HBV markers 1
• Hepatitis A vaccination is recommended for HBV carriers who are negative for anti-HAV, as coinfection increases mortality risk by 5.6- to 29-fold 1