[Rubella virus. II. Replication in Vero calls and effects of actinomycin Dand cycloheximide]

Budding at the plasmic membrane is the primary mode of production of rubella virus in Vero cells. Intense cytopathic effect is observed even if only 10% of the cells are infected. Actinomycin D has little effect on the multiplication of rubella virus but cycloheximide inhibits its growth. This inhibitiion is probably due to the reduction of cellular protein synthesis and not to a direct action of the inhibitorson the virus multiplication. Viral proteins in infected cells have not been demonstrated. The presence of a viral substance inhibiting normal cellular synthesis is discussed.