What is the "window period" for HIV?
It can take up to 3 months after HIV infection for enough antibodies to develop, therefore a negative test result is reliable only if the person has not had any sexual or needle-sharing risk behavior (or other exposure to infectious body fluids) during the 3 months prior to testing. Some people with recent risk behavior will test HIV antibody negative, yet may have actually been infected during the previous 3 months. Every exposure pushes the window period out another months.
Last modified on 01/08/2015