This test detects antibodies the body produces in response to HIV infection. Most current screening tests are fourth-generation assays that detect both HIV antibodies and the p24 antigen, allowing earlier detection — often within 2-4 weeks of exposure.
This test is recommended at least once for all adults and adolescents, more frequently for those at higher risk, and during pregnancy. A positive screen is followed by confirmatory testing that distinguishes HIV-1 from HIV-2 and rules out false positives. With modern antiretroviral therapy, HIV is a manageable chronic condition, making early diagnosis essential. Sample type is serum or plasma.