If you want to be sure that the patient is infected with HIV, you should go to the hospital and have your blood tested for HIV antigens or antibodies, but this is only a preliminary test. If this test is done after the window period and is negative, AIDS can be ruled out. If the antigen and antibody test is positive, the patient can be initially determined to be infected with HIV, but it is not certain that the patient is infected with HIV and further testing at the CDC is needed to confirm the diagnosis. The doctor at the CDC will use protein blotting to test the patient’s blood again for the presence of HIV antibodies. If HIV antibodies are also detected in the patient’s blood by protein blotting, the patient can be confirmed to be infected with AIDS, and in this case, antiviral treatment can be administered to prevent the patient from progressing to the AIDS stage.