The in vitro activity of Acyclovir and related compounds against cytomegalovirus infections

The anti-viral effect of Acyclovir against the replication of human cytomegalovirus and murine cytomegalovirus was determined by a plaque reduction method. Eight strains of human cytomegalovirus were sensitive to the effect of Acyclovir but this compound was a more effective inhibitor of the replication of murine cytomegalovirus in both plaque reduction and virus yield experiments. Further studies with herpes simplex viruses indicate however that the quantitative difference in the effect of Acyclovir against the two cytomegaloviruses is a reflection of the obligatory use of different host cell species. These studies show also that the replication of both cytomegaloviruses is less sensitive to the effect of Acyclovir than either herpes simplex virus type I or II in appropriate host cell systems. The results obtained were compared with known inhibitors of herpes simplex virus replication.