Many people are very afraid of AIDS and do not know when to do the test after having high-risk behavior, which causes great harm to physical and mental health and seriously affects work, study and life. The following is provided to the general public in the form of science, and we hope it can bring you help. The best time to get tested for HIV is a very important thing for a person who is suspected to be infected. Because people with AIDS rarely show any unusual symptoms in the early stages, they are often overlooked. It is not easy to get treatment until the symptoms are detected. Therefore, it is very important to detect and prevent HIV infection in the early stages of infection to greatly reduce the chance of infecting others. It generally takes 2-4 weeks after high-risk behavior to detect HIV antibodies to AIDS. HIV antibodies can be detected 2 weeks after high-risk behavior, which means that it is appropriate to do HIV antibody testing after 2 weeks. The more time that passes, the more accurate the test will be; the vast majority of people infected with HIV will be able to produce enough antibodies after 4 weeks. It is important to note that there is a “window period” for HIV infection in humans. The length of the window period varies from person to person, and is approximately 2 weeks to 3 months. The window period should be calculated from the time of high-risk behavior or blood transfusion, and the average time to develop serum antibodies after HIV infection is 45 days or less. The average time to develop serum antibodies after high-risk behavior is 2-8 weeks, which should be a good time frame for testing. Test results within the window period of HIV are not final. The current window period is 3 months after high-risk behavior, as determined by domestic experts. The latest research by renowned expert Professor Cao Yunzhen shows that the window period is 6 weeks or 42 days. It is extremely rare that an individual does not produce serum antibodies after 3 months of HIV infection, and a negative test at 3 months does not require further testing unless the individual is extremely fearful or has engaged in high-risk behavior. Suggestions: Scientific research shows that: 2-4 weeks after high risk, the initial test, full 4 weeks of negative results, the infection rate can be ruled out about 98%; full 8 weeks after the retest, the results are negative, the infection rate can be ruled out 99.99%; only about one in 10,000 people window period in 8 weeks to 3 months, in order to 100% rule out the possibility of infection, it is best to full 3 months to do the final retest, negative can be completely ruled out.