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What is A person is HBsAg positive, but anti-HBsAg negative, what should be the next step and explain in detail?
HBsAg indicates a current infection.Anti-HBs is generally interpreted as indicating recovery and immunity from hepatitis B virus infection. Anti-HBs also develops in a person who has been successfully vaccinated against hepatitis B.HBeAg is a hepatitis B viral protein. It is an indicator of active viral replication.HBcAg (core antigen) is a hepatitis B viral protein. It is an indicator of active viral replication.*replicative phase is characterized by the presence in the serum of HBeAg and HBV DNA levels well in excess of 10^3-10^4 IU/mL** chronic HBV infection can occur in the presence or absence of serum hepatitis B e antigen (HBeAg), the level of HBV DNA correlates with the level of liver injury and risk of progression.