: HTLV-III Antibody Screen with Confirmation, Serum or Plasma

: What This Test Looks For

: The test detects antibodies that a person's immune system produces in response to HTLV-III, now classified as HIV-1. Antibodies are proteins made by the body in response to infection, and their presence can indicate prior or current HIV-1 infection once confirmed by supplemental testing.

: Why the Test Is Ordered

: Clinicians order this test to evaluate possible HIV-1 infection after exposure or when symptoms or risk factors are present. It may also be used for screening in some clinical or public-health settings, where a reactive result requires additional confirmation.

: How the Screening and Confirmation Work

: An initial immunoassay is performed on serum or plasma. If the screen is reactive, it is not automatically a diagnosis; confirmatory testing is needed to distinguish true HIV-1 antibody positivity from false-reactive screen results. The exact confirmatory method used should be identified by the performing laboratory.

: What a Result Means

: A nonreactive screen generally means no antibody evidence of HTLV-III/HIV-1 infection was detected at the time of testing, though recent exposure can be too early to detect. A reactive confirmed result indicates HIV-1 infection and requires clinical follow-up; results should be interpreted with the testing method, timing of exposure, and clinical context in mind.