Which hepatitis B serologic pattern indicates a patient who was successfully vaccinated?
Answer and explanation
Correct answer: C. Positive anti-HBs only
- Step 1: The vaccine contains only the surface antigen, so it produces only anti-HBs. Step 2. A natural infection that resolved also produces anti-HBc. Answer: positive anti-HBs only. Why not the others: HBsAg with IgM anti-HBc is acute infection, anti-HBs with anti-HBc is resolved infection and HBsAg alone is chronic or early infection.
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