Respiratory syncytial virus is a common virus which frequently causes severe lower tract disease in immunocompromised patients. The mortality rate in bone marrow transplant patients with lower tract disease varies from 31% to 100%, depending upon the treatment used, time before initiation of treatment, and whether patients are pre- or post-engraftment. Therapy with inhaled ribavirin has been used with limited success in decreasing mortality rate. Because of concern about conversion from upper respiratory tract disease to lower respiratory tract disease, we conducted a pilot study using aerosolized ribavirin in asymptomatic RSV-positive patients. Patients had NP washes performed on a weekly basis during the RSV season, for the presence of RSV. If patients were positive, but asymptomatic, and could have their transplant postponed, they were treated with ribavirin until negative. Patients who could not be postponed received aerosolized ribavirin, and began transplant conditioning. During this study, we performed 145 nasal aspirations for RSV on 25 patients; 10 aspirates were positive in seven asymptomatic patients. All positive events were successfully treated with ribavirin, which cleared the RSV for a minimum of 3 weeks. No patients became symptomatic. Thus, we conclude that ribavirin can clear asymptomatic infections in immunocompromised pediatric transplant patients.