Problems associated with the use of (E)-5-(2-bromovinyl)-2'-deoxyuridine for typing herpes simplex virus.

When 0.5 microgram of (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVdU) per ml was incorporated directly into cell culture medium inoculated with eight known positive specimens, one herpes simplex virus type 1 (HSV-1) isolate grew in the presence of BVdU and was misidentified. By plaque assay, the titers of 15 HSV-1 strains were reduced by more than 3 log10 by BVdU, and the titers of 16 HSV-2 strains were reduced by less than 2 log10. Titers of HSV-1 acyclovir-resistant strains were reduced by less than 1.5 log10, which was characteristic of HSV-2 strains. Thus, typing of HSV isolates in the presence of BVdU by plaque assay is reliable only if information regarding previous antiviral therapy is obtained.