Setting up an HIV screening program

Human immunodeficiency virus-1 (HIV-1) screening programs currently are based primarily on the detection of specific HIV-1 antibodies by the commercially available enzyme immunoassay (EIA) combined with highly specific confirmation procedures. Factors to be considered in establishing a screening program include test performance characteristics, economy, confidentiality and notification procedures, legal and regulatory issues, proficiency and quality control measures, and laboratory safety. Commercial EIA screening in conjunction with a licensed Western blot assay permits the classification of all but a few serum samples into HIV-1-positive and HIV-1-negative categories. The occasional indeterminate results often can be resolved by following a defined retesting/resampling algorithm or by using research-level test procedures that may become available for diagnostic use in the future. Although screening of patient populations with an increased risk of HIV-1 exposure will improve the predictive accuracy of an initial screening assay, confirmation testing should nonetheless be performed for all EIA reactive sera regardless of the source. Local HIV-1 screening programs that meet minimum-volume requirements can result in considerable savings and flexibility for a moderate-size institution. However, before this type of program is undertaken, numerous technical and ethical considerations need to be addressed.