What will be positive in the serum of a patient who has received 3 doses of the Hepatitis B Virus (HBV) vaccine, Hepatitis B surface antibody (HBsAb)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: September 2, 2025 • View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Hepatitis B Serology After Vaccination

After receiving 3 doses of the Hepatitis B virus (HBV) vaccine, the patient will have positive Hepatitis B surface antibody (HBsAb/anti-HBs) in their serum, corresponding to answer choice C. 1, 2

Explanation of HBV Vaccination Response

The hepatitis B vaccine contains purified hepatitis B surface antigen (HBsAg), which stimulates the immune system to produce antibodies against this antigen (anti-HBs). This immune response is what provides protection against HBV infection.

Expected Serological Findings After Vaccination:

  • HBsAb/anti-HBs: POSITIVE (≥10 mIU/mL is considered protective)
  • HBsAg: NEGATIVE (this is the viral antigen, not present in vaccinated individuals)
  • HBeAg: NEGATIVE (this is a marker of viral replication, not present in vaccinated individuals)
  • HBcAb/anti-HBc: NEGATIVE (this indicates past or current infection, not vaccination)

Interpretation of Answer Choices

  1. HBsAg (Choice A): This is incorrect. HBsAg is the surface antigen of the hepatitis B virus and indicates active infection. The vaccine does not contain live virus and cannot cause HBsAg positivity. 1

  2. HBeAg (Choice B): This is incorrect. HBeAg is a marker of viral replication and high infectivity. It is not produced in response to vaccination. 1

  3. HBsAb +ve (Choice C): This is correct. Anti-HBs (HBsAb) is the protective antibody produced in response to HBV vaccination. Postvaccination serologic testing typically shows anti-HBs ≥10 mIU/mL 1-2 months after completing the 3-dose series, indicating immunity. 1

  4. HBcAb and HBsAb +ve (Choice D): This is incorrect. While HBsAb will be positive after vaccination, HBcAb (antibody to hepatitis B core antigen) indicates past or current HBV infection, not vaccination response. The vaccine does not contain core antigen and therefore does not stimulate production of anti-HBc. 1, 2

Clinical Implications

  • Postvaccination serologic testing is recommended 1-2 months after the final dose for certain groups, particularly healthcare personnel and immunocompromised individuals. 1
  • A protective anti-HBs level (≥10 mIU/mL) indicates successful immunization. 1
  • Individuals who do not develop adequate anti-HBs levels after the primary series (non-responders) may require additional doses. 2

Common Pitfalls to Avoid

  • Confusing natural infection with vaccination: Natural HBV infection results in multiple serological markers (potentially including HBsAg, HBeAg, anti-HBc, anti-HBe, and eventually anti-HBs), while vaccination only produces anti-HBs. 1

  • Testing too soon after vaccination: Testing for anti-HBs should be performed 1-2 months after the final vaccine dose for accurate assessment of immune response. 1

  • Misinterpreting waning antibody levels: Anti-HBs levels may decline over time after vaccination, but immunologic memory typically persists and provides ongoing protection. 1

References

1
Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

2
Guideline

Hepatitis B Vaccination Guideline

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Related Questions

What is the significance of having antibodies against the hepatitis B virus (HBV) surface antigen at a level of 147 mIU/ml in an individual with human immunodeficiency virus (HIV) induced immunosuppression?
What does a non-reactive Hepatitis B (Hep B) core antibody result indicate about an individual's immunity to Hepatitis B?
Should an individual with positive Hepatitis B core antibody (HepBcAb) and negative Hepatitis B surface antibody (HepBsAb) receive the Hepatitis B vaccine?
What are the tests for Hepatitis B (HBV) infection?
What are the indications for a 4-dose Hepatitis B (Hep B) vaccine series?
What is the risk of death associated with using midazolam (Benzodiazepine) 15mg orally, combined with a topical anesthetic and vasoconstrictor for hair implantation?
What is the management for neutrophilia with a neutrophil count of 81.4%?
What are the anesthetic implications of a left atrial clot?
What is the treatment for a 3% increase in serum sodium, or mild hypernatremia?
What is the recommended treatment for bacterial vaginosis using Metronidazole (antibiotic)?
What are the guidelines for mitral valve replacement surgery in patients with left atrial thrombus?

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.

Ask Question