Acquired immunodeficiency syndrome (AIDS) is caused by two types of human immunodeficiency viruses, collectively designated HIV. HIV is transmitted by sexual contact, exposure to blood or blood products, and prenatal or perinatal infection of a fetus or newborn. Antibodies against HIV are nearly always detected in AIDS patients and HIV-infected asymptomatic individuals. This assay is used for simultaneous qualitative detection of human immunodeficiency virus (HIV) p24 antigen and the antibodies to HIV Type 1 and/or HIV Type 2. Early after infection with HIV-1, but prior to seroconversion, HIV-1 core protein p24 antigen, may be detected in HIV-1 infected individuals. The detection of the antigen allows for earlier detection of HIV infection. All reactive screens are reflexed to confirmatory testing. If the confirmatory results are inconsistent with the screening results, additional testing using HIV Nucleic Acid Testing is strongly recommended.