The shell vial culture assay has greatly decreased the time to laboratory detection of many viruses. Reports have suggested that the use of shell vials alone without concomitant conventional tube cultures may result in the laboratory missing a small percentage of positive specimens which have a low titer of virus. A method which increases the sensitivity of the shell vial would be advantageous to the clinical laboratory in that the expense and time expended in using conventional tube cultures would be saved. It has been shown that rolling and orbital motion have a positive effect on herpesvirus replication in tube cultures and shell vials. We hope to demonstrate that by incubating shell vial viral cultures on an orbital rotator not only an increase in the number of positive cultures will result as compared to stationary cultures, but also a decrease in the time to positivity and an increase in degree of positivity will be seen.