Several antiviral compounds have been developed during the last decade. One such compound is ribavirin, a synthetic nucleoside structurally related to guanosine. Ribavirin therapy has been successfully used against

Ribavirin is effective to varying degrees against several RNA- and DNA-containing viruses in vitro. It has been approved for aerosol treatment of respiratory syncytial virus infections in infants. Intravenous administration has proved effective in treating Lassa fever.