Negative HIV nucleic acid test after two weeks can basically rule out the infection, and it is recommended to re-test the HIV antibody after 3 months, if it is negative, the infection can be ruled out. The window period of HIV nucleic acid test is about one week, that is, about one week after high-risk behavior, if the nucleic acid test result is negative, most of the infections can be ruled out, so after two weeks of negative nucleic acid test can basically rule out the possibility of infection. Since there are individual differences in the length of the window period, it is recommended that the test be repeated three months after high-risk behavior to completely rule out the risk of infection. Sexual transmission is the main mode of HIV transmission, and avoiding high-risk sexual behavior can effectively reduce the possibility of infection. Taking a full course of blocking medication within 2 hours of high-risk behavior can greatly reduce the risk of infection. If HIV infection is suspected, it is recommended that you seek medical attention and follow the doctor’s instructions for examination and treatment.