Evaluation of Immunoglobulin G Responses to and in Malian School Children Using Multiplex Bead Assay.

Malaria serology through assaying for IgG against spp. antigens provides evidence into the infection history for an individual. The multiplex bead assay (MBA) allows for detection of IgG against multiple spp., and can be especially useful in many regions where is of primary clinical focus, but other species are co-endemic. Dried blood spots were collected from 805 Malian children attending 42 elementary schools in the regions of Mopti, Sikasso, Koulikoro, and Bamako capital district, and IgG assayed by MBA. As southern Mali is known to be holoendemic for , merozoite surface protein 1 19-kDa subunit (MSP-1) and apical membrane antigen 1 (AMA-1) antigens were included for serology against this parasite. Responses to these antigens both provided high estimates for lifetime exposure, with 730 (90%) children with IgG antibodies for MSP-1, 737 (91%) for AMA-1, and 773 (96%) positive for either or both. Also included was the antigen MSP-1, against which 140 (17.4%) children were found to have antibodies. Increases in antibody titers with older age were clearly seen with the antigens, but not with the antigen, likely indicating more of a sporadic, rather than sustained transmission for this species. The MBA provides effective opportunities to evaluate malaria transmission through serological analysis for multiple species.