(Science: investigation) The enzyme-linked immunoabsorbent assay is serologic test used as a general screening tool for the detection of antibodies to the hiv virus. Reported as positive or negative. Since false positive tests due occur (for example recent flu shot), positives will require further evaluation using the western blot. Elisa technology links an a measurable enzyme to either an antigen or antibody. In this way, it can then measure the presence of an antibody or an antigen in the bloodstream.