<prompt> Hepatitis B infectivity is indicated by:Anti-HBsAgHBsAg HBeAgAnti-HBsAg - Anti-HBcAnti-HBeAg Anti-Hbs Ag  <response>: Answer is B HBs Ag HBe Ag HBe Ag: Its principal clinical usefulness is an indicator of relative infectivity - Harrison HBs Ag: Its presence in serum indicates infection pervious vaccination with hepatitis B virus. HBs Ag Anti- HBsAg Anti Hbe HBe Ag Anti-Hbe Acute HBV infection High infectivit - IgM - Chronic HBV infection High infectivity - IgG - Thus, the presence of the above two markers indicate an infection with hepatitis B virus and high infectivity. Q Whether the infection is acute or chronic can, however, only be commented if status of anti-HBe marker is dear. 