BACKGROUND: Viral loads (VLs) frequently are followed during treatment of symptomatic congenital cytomegalovirus disease, but their predictive value is unclear. METHODS: Post hoc analysis of 2 antiviral studies was performed. Seventy-three subjects were treated for 6 weeks and 47 subjects were treated for 6 months. Whole blood VL was determined by real-time polymerase chain reaction before and during therapy. RESULTS: Higher baseline VL was associated with central nervous system involvement (3.82 log, range 1-5.65 vs 3.32 log, range 1-5.36; P = .001), thrombocytopenia (3.68 log, range 1-5.65 vs 3.43 log, range 1-5.36; P = .03), and transaminitis at presentation (3.73 log, range 1-5.60 vs 3.39 log, range 1-5.65; P = .009), but with overlap in the amount of virus detected between groups. In subjects treated for 6 months, lower VL at presentation correlated with better hearing outcomes at 12 months, but VL breakpoints predictive of hearing loss were not identified. Sustained viral suppression during 6 months of therapy correlated with better hearing outcomes at 6, 12, and 24 months (P = .01, P = .0007, P = .04), but a majority without viral suppression still had improved hearing. CONCLUSIONS: In infants with symptomatic congenital cytomegalovirus disease, higher whole blood VL before initiation of antiviral therapy has no clinically meaningful predictive value for long-term outcomes.