Human immunodeficiency virus type II (HIV-2) testing: a perspective.

Testing of blood for antibodies to the human immunodeficiency virus type 2 (HIV2) has begun. A major benefit of this testing will be the elimination of the exclusion of blood donors on the basis of geographic origin. Will this test be helpful? Present anti-HIV1 testing detects between 60 to 90 percent of those samples containing the HIV2 antibody. A Food and Drug Administration (FDA) licensed enzyme immunoassay for HIV1/HIV2 antibodies became available for clinical use in March of 1992. (There is an FDA unlicensed HIV-2 Western Blot (WB) Test). The specificity and sensitivity of either the HIV2 EIA or HIV2 WB are not well defined. In a survey of 24 million U.S. donors, no antibodies to HIV2 were detected. With the incidence of HIV2 infection being so small, it is probable that the majority of positive tests will be false-positives causing needles concern for the blood donor who must be counseled. The benefits to the blood supply remain to be evaluated.