Previous studies have demonstrated that respiratory syncytial virus (RSV) infection of airway epithelial cells results in the expression of a number of cytokines, such as interleukin-8 (IL-8), that are transcriptionally regulated by nuclear factor kappaB (NF-kappaB). In the studies reported here, we demonstrate that treatment of RSV-infected A549 cells with 100 microg of ribavirin (a viral replication inhibitor) per ml results in reversal of RSV-induced NF-kappaB activation, IL-8 mRNA expression, and IL-8 protein production in A549 cells. These data confirm that viral replication is a key step in RSV-induced NF-kappaB activation and IL-8 production.