There is no specific number of times that HIV exclusion testing needs to be done, but a single negative HIV antibody screening test checked after 6 weeks of high risk basically excludes HIV infection. According to the National Health Commission’s Diagnosis of AIDS and HIV Infection criteria, which went into effect on July 1, 2019, the window period, during which a patient is positive for the virus and negative for viral antibodies, is usually 2-6 weeks. After the window period, an HIV antibody screening test is performed, and a reactive screening test result suggests possible HIV antibody positivity, which needs to be confirmed with additional confirmatory tests. A non-responsive screening test is reported as HIV-negative. Therefore, after high-risk behaviors, it is necessary to have several consecutive tests, and just one test is not enough. It is generally recommended to have a test once a month for 3-6 months. If each test is negative, the test can be confirmed.