To check for HIV infection, you need to register with the Department of Infectious Diseases or the Department of Dermatology and Venereology, or you can go to the local CDC department for examination. The main test for AIDS is to draw blood for HIV antibodies, and if the antibodies are positive, a confirmatory test is needed to clarify. If the confirmatory test is clear, the diagnosis will be clear. If the confirmatory test is negative, a positive initial screening test is a false positive and is usually fine. If the HIV antibody is negative and the window period is ruled out, it indicates no infection. For HIV, especially for high-risk groups, regular screening at the local CDC is required to prevent cross-contamination of HIV infection to others.