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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Infection /multipilcation of HBsAg is best/commonly diagnosed by -
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The correct answer is  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 PANIKER'S TEXTBOOK OF MICROBIOLOGY 9TH EDITION PAGE NO-547