For forward versus side scatter analysis, MB114 cells harvested at six days post-infection were analyzed. Uninfected MB114 cells were detached from flasks with 0.5 mM EDTA and analyzed in parallel with infected cells. In certain experiments, to determine the effect of viral DNA replication and/or late gene synthesis on forward and side scatter properties, MB114 cells were treated with 200 mg/mL phosphonoacetic acid (PAA) after one hour of infection. At six days post-infection, non-adherent cells were harvested and counted by trypan blue exclusion to determine the percent of cells infected that were viable and non-adherent at time of harvest. Cells which remained adherent to the flask were then detached with 0.5 mM EDTA, combined with the harvested nonadherent cells, and analyzed by flow cytometry for forward and side scatter properties. Effective block of late gene synthesis was confirmed by plaque assay titer of treated cells. Viral titer was reduced 96.2% after 24 hours and 99.9% after six days as compared to untreated cells. 10 micron control beads were run in parallel with each experiment (Beckman Coulter, Fullerton, CA).