To assess the effect of GA on HCMV infection, dilutions of 1 µM to 20 µM were made (Fig. 1A). Monolayers of human foreskin fibroblasts (HFF) were incubated for 1 hour with GA and then infected with two cell-associated clinical isolates of HCMV: CH1914 and BI-615. Because neither virus produces extracellular virus, plates for plaque assays were inoculated with 50–100 infected cells per well, and then treated with medium containing 1–20 µM GA, or vehicle control. Viral infection was allowed to progress for 7 days, and then quantitated by plaque reduction assay14. GA inhibited infection of BI-6 and CH19 with an IC50 of 7.26 ± 0.92 μM and 6.83 ± 1.08 μM, respectively.