16 drugs robustly block ZIKV infection in human Jeg-3 cells. (A) Jeg-3 cells were infected with three different strains of ZIKV and the infection was monitored by microscopy (anti-flavivirus envelope, 4G2, green; nuclei, blue). (B) Schematic of the screening strategy where ammonium chloride (NH4Cl) was used as a positive control. (C) Z-scores of the percent infection of replicate 1. (D) Z-scores of replicate 1 plotted against replicate 2. (E) The 15 drugs that inhibit infection >3-fold that are nontoxic. IC50 values for ZIKV (Mex2-81) (uM), IC50s for protection from ZIKV-induced death for ZIKV (Mex2-81) (uM), and CC50 values are shown.