If a Hepatitis B screening shows HBsAg negative and anti-HBc positive, what does this indicate?

The presence of a negative HBsAg (Hepatitis B surface antigen) along with a positive anti-HBc (antibody to hepatitis B core antigen) indicates that the individual has likely experienced a past Hepatitis B infection that has resolved. This combination suggests that the person has developed immunity due to natural infection, rather than vaccination.

Natural immunity occurs when the immune system has responded to a real infection, producing antibodies as a result. The anti-HBc remains positive even after the infection has cleared, serving as a marker of previous exposure. In contrast, the negative HBsAg signifies that the person is not currently infected with the virus. Additionally, individuals who have been vaccinated for Hepatitis B would typically show positive anti-HBs (antibody to hepatitis B surface antigen) rather than anti-HBc, which further supports the conclusion of natural immunity following past infection.