Most HIV tests check for antibodies that the body produces once infected with HIV. Antibodies are proteins that the immune system produces to fight off different kinds of infections, including HIV. If an HIV test detects HIV antibodies, a person is infected with HIV.
If antibodies are not present, a person is considered non-reactive for HIV. It can take as long as 90 days for the body to develop enough antibodies to be measurable on this type of test. The time period between HIV exposure and a positive test is called the “window period,” during which you could test non-reactive for HIV but still be infected with HIV and able to transmit the virus to others. It is important to get tested (or re-tested) after a sufficient period of time has passed to know for sure.
Posted in: Testing