If you have had a negative HIV test 12 months after a possible exposure then you do not have HIV.
While it is true that some medical conditions can cause a positive result to be delayed, this is considered when window periods for the different HIV test are given. Using the Fourth Generation HIV test, most people who have been infected with HIV will test positive 6 weeks after infection but we tell people it can take up to 90 days because certain conditions may delay a positive result. If you have a negative test result after 90 days, you were not infected with HIV.
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