In November 2011 I had the following test results: HBsAg (negative), HBsAb (positive). On September 1 2012, I tested again and the results were different - HBsAg (negative), HBsAb (negative). Can someone help me better understand how the antibody test can go from positive to negative? For your information, I was also found to be suffering from Epstein Barr virus as of March 2012. All of these difficulties followed an episode with a massage girl in Thailand. I gave and received (unprotected) oral sex. Tested out negative to 14 months for HIV. Not feeling well. Any idea what might be going on?