Abstract
Summary
An overlay employing tragacanth gum as a substitute for agar in the plaque assay of animal viruses is described. The tragacanth overlay was successfully employed with vesicular stomatitis virus (a rhabdovirus), foot and mouth disease virus (a picornavirus), pseudorabies virus (a herpes virus), African horse sickness virus, and measles virus (a paramyxovirus). Plaques under tragacanth were generally smaller but usually equalled or slightly exceeded counts obtained under the agar. The number of plaques developing with measles virus in BSC-1 cells was shown to be directly proportional to the virus concentration and the two variables were shown to have a linear relationship. Tragacanth is easy to prepare, the cells used tolerated long exposure to the material, and it was easier to remove than previously described overlays.
Get full access to this article
View all access options for this article.