The observed viability of endothelial cells after cHV68 infection could be the result of escape from infection or latent infection of these cells. To determine the infection status of the intact endothelial cells, we performed RT-PCR analysis of viral gene transcripts. The cHV68 M2 gene transcript is synthesized during both lytic and latent infection, as are the polymerase III (pol III) transcripts encoded at the left end of the viral genome [21, 22] . Latently infected S11 cells contained both pol III-1 and M2 transcripts (Fig. 3A) . We detected these transcripts in 3T3 fibroblasts at 24 and 36 hours post-infection, as well as from the 3T3 cellular debris harvested at six days post-infection, while no cellular b-actin transcript was detected from infected 3T3 cells at 36 hours post-infection. No RNA could be detected from infected 3T3 debris at 12 days post-infection, whereas we recovered RNA from infected MB114 cells as far as 12 days post-infection. Pol III-1 and M2 transcripts were detected in infected MB114 cells at 24 and 36 hours post-infection and from the intact, cultured cells at six and 12 days post-infection. We detected b-actin RNA in infected MB114 cells at 24 and 36 hours post-infection, but not at six and 12 days post-infection. However, we detected another cellular mRNA transcript, cyclophilin A, at six days post-infection in 3T3 fibroblasts and MB114 cells (Fig. S2) , and comparable detection of the cellular 18S rRNA transcript was observed in all conditions. Gradual loss of the cellular b-actin transcript in viable cells was not surprising given that b-actin has been documented to vary significantly in the setting of virus infection [23] , and selective degradation of certain mRNAs frequently occurs during virus infection [24] [25] [26] [27] [28] . Analysis of viral gene transcripts indicated that those endothelial cells which remained intact after cHV68 infection contained viral gene transcripts as far as 12 days postinfection.