Figure 7. Representative platelet aggregometry performed on a 1:1 mix of platelet-rich plasma from a healthy control (HC) participant and platelet-poor plasma dialyzed to remove EDTA from either healthy controls or acute Lassa fever (LF) patients, Sierra Leone, 2015–2018. Aggregation was stimulated by addition of 5 μmol ADP. Plasma from fatal LF cases caused a decrease in aggregation at 4 min compared with peak aggregation, but plasma from LF survivor and non–LF febrile controls (NLFCs) showed no disaggregation by 4 min. A) Percent aggregation over 4 min. B) Aggregation at 4 min divided by the maximum aggregation in assays by using plasma from 14 fatal LF cases, 7 nonfatal LF cases, and 5 NLFC cases. Only assays using plasma from fatal cases showed disaggregation by the experimental endpoint. Error bars shows SD; horizontal lines indicate means. HC, healthy control; LF, Lassa fever; NLFC, non-LF febrile control.