The HIV antigen antibody test is performed about 4 weeks after the occurrence of high-risk behavior. High-risk behavior refers to unprotected sex with a person with HIV or a stranger, shared use of syringes, input of unproven blood or blood products of unknown origin, and of course other high-risk behaviors, and the diagnosis is basically confirmed by testing about 4 weeks. If the HIV viral load, also known as nucleic acid testing, can detect the virus in the infected person in about 7-10 days, which is currently a relatively fast method. Most hospitals now recommend that patients be retested in about 3 months to further clarify whether they are infected.