Which statement correctly describes the criterion for chronic carrier status with respect to HBsAg?

• A. HBsAg positivity for at least 6 months
• B. HBsAg positivity for at least 3 months
• C. HBsAg positivity for at least 12 months
• D. HBsAg positivity for at least 1 month

Answer: (A)

Chronic HBV carrier status is defined by persistence of HBsAg for six months or longer. In most people with acute HBV infection, HBsAg appears early and clears within about six months. If HBsAg remains detectable for six months or more, it indicates the infection has become chronic and the person is a carrier. Shorter durations, like three months or one month, can occur during the course of an acute infection or its early resolution, so they aren’t reliable indicators of chronicity. A full year of persistence would also indicate chronic infection, but the standard clinical threshold used to define chronic carrier status is six months.