Question

Which serum marker appears after successful Hepatitis B vaccination?

• A. Anti-HBsAg
• B. Anti-HBeAg
• C. Anti-HBcAg
• D. HBsAg

Hint:

The vaccine carries only surface antigen, so the antibody formed is against it.

Answer 1

The Correct Option is A

Step 1: Remember what is inside the hepatitis B vaccine. It is a recombinant preparation of surface antigen alone, with no core or e antigen.

Step 2: Because only surface antigen is presented, the single antibody a vaccinated person develops is anti-HBs, and its rise above the protective level signals successful immunity.

Step 3: This is why anti-HBc is a useful discriminator. Its presence means the person met the whole virus through natural infection rather than the vaccine. Anti-HBe likewise tracks infection, and detectable HBsAg indicates ongoing infection or carriage.

Step 4: The lone marker expected purely from vaccination is anti-HBs.

\[\boxed{\text{Anti-HBsAg (anti-HBs)}}\]