FIGURE 1.

Flavivirus does not kill epithelial cells or fibroblasts. A, MDCK renal epithelial cells infected with Modoc virus at various m.o.i. show no significant death when analyzed by trypan blue exclusion, even very late following infection with high m.o.i. B, no significant death is observed following infection with Modoc virus at m.o.i. = 10 in several other cell types as late as 144 hpi. Because background cell death varied by cell type and condition, living and dead cells were counted, and percent cell death was calculated as % cell death above mock infection. Each assay was run in triplicate.