<prompt> Infection multipilcation of HBsAg is bestcommonly diagnosed by -HBeAgHBsAgHBV DNAAnti HBs Ag  <response>: HBeAg appears in blood concurrently with HBsAg or soon afterwards. Circulating HBeAg is an indicator of active intrahepatic viral multiplication, and the presence in blood of DNA polymerase ,HBV DNA and virions ,reflecting high infectivity. REF:ANANTHANARAYAN AND PANIKERS TEXTBOOK OF MICROBIOLOGY 9TH EDITION PAGE NO-547 