Is a 4th gen ab/ag hiv test accurate after 21 days of exposure or what % of accuracy i can expect from it as many doctors say 4th gen is reliable after 28 days?

HIV: Typical testing regimen is at 1 month (more than 28 days) and 6 months. If either is positive, you will be offered medications that reduce the viral load in your bloodstream. You should talk to your Dr about using PrEP while you are waiting for results, and even if they come back negative. These prophylactic meds can prevent HIV infection during high risk encounters.