A surgeon has tested positive for the hepatitis B surface antigen (HBsAg). How long should the surgeon be restricted from work?

• A. Until antiviral therapy reduces HBV DNA
• B. Until they test negative for HBsAg
• C. Until symptoms resolve
• D. Until six months have passed

Answer: (B)

HBsAg positivity means the person currently has hepatitis B and can transmit the virus through blood and body fluids. In healthcare settings, the decision to restrict a clinician from performing exposure-prone procedures is based on whether they are still infectious, as indicated by the presence of surface antigen. Antiviral therapy can lower viral replication (HBV DNA), but it does not reliably indicate non-infectious status because surface antigen can remain detectable even when DNA levels are reduced. Symptoms don’t reflect infectiousness, since someone can be infectious without noticeable illness. A fixed time frame like six months isn’t the criterion used in these safety guidelines. Therefore, the restriction is maintained until the surface antigen is no longer detectable, signaling reduced or absent infectivity.