If the test is negative at five months, AIDS can be ruled out. In fact, with the rapid advances in HIV testing technology, the window period for HIV is advancing and it does not take as long as five months to rule out HIV. The more widely used technologies, such as the HIV antibody test, can detect HIV antibodies in an infected person in as little as 3-4 weeks. The antigen antibody to HIV, which is a 4-generation test, can be detected in an infected person in about 2-3 weeks. If HIV-RNA, the nucleic acid viral load of AIDS, is used for testing, the virus can be detected in the body 7-10 days after infection and the diagnosis can be confirmed. Therefore, if you want to be tested for HIV, you should do so 4 weeks after having high-risk sex.