[The synergistic antiviral effect of acyclovir and ribavirin against the herpes simplex type-1 virus and the pseudorabies virus in vitro].

The antiviral effect of the combination acyclovir (ACV) and ribavirin (R) on herpes simplex virus type 1 (HSV-1) in diploid cell culture of human embryonal skin and muscle fibroblasts and the virus of pseudorabies in secondary culture of chicken embryonal fibroblasts is studied. The antiviral activity is studied under the checker-board combinations of twofold dilutions of the two substances on the basis of inhibition of the virus cytopathic effect in microplates. The viruses are applied at 100 CCID50, per 0.1 cm3 in each well. Dose isobologrammes are made which point out to the synergistic type of interaction of the substances in the combination in relation to the two viruses. The concentrations with maximal synergistic effect in relation to HSV-1-1.1 for ACV and 41 mu for R respectively, and in relation to the virus of pseudorabies of 3.3 and 9.2 M respectively, are established.