Standardization of immunoglobulin M capture enzyme-linked immunosorbent assays for routine diagnosis of arboviral infections

Immonoglobulin M antibody-capture enzyme-linked immunosorbent assay (MAC-EL ISA) is a rapid and versatile diagnostic method that readily permits the co mbination of multiple assays, Test consolidation is especially important fo r arthropod-borne viruses (arboviruses) which belong to at least three viru s families: the Togaviridae, Flaviviridae, and Bunyaviridae. Using prototyp e viruses from each of these families and a panel of well-characterized hum an sera, we have evaluated and standardized a combined MAC-ELISA capable of identifying virus infections caused by members of each virus family, Furth ermore, by grouping antigens geographically and utilizing known serological cross-reactivities, we have reduced the number of antigens necessary for t esting, while maintaining adequate detection sensitivity. We have determine d that a 1:400 serum dilution is most appropriate for screening antiviral a ntibody, using a positive-to-negative ratio of greater than or equal to 2.0 as a positive cutoff value. With a blind-ceded human serum panel, this com bined MAC-ELISA was shown to have test sensitivity and specificity that cor related well with those of other serological techniques.