Respiratory syncytial virus (RSV) causes lower respiratory tract infections such as bronchiolitis and pneumonia in infants, young children and adults. In the absence of an effective vaccine and less controversial compounds to prevent or ameliorate RSV infections, RSV remains a serious health threat and a sustained effort must be mounted to find new agents with enhanced efficacy. We have identified an Ethnobotanical (EB) preparation (ZX-2187P) that shows significant anti-RSV activity. The overall scope of this application is to investigate the potential of this EB preparation as a therapeutic for controlling RSV infections. The specific aims include, evaluation of anti-RSV activity of ZX-2187P against multiple RSV strains in multiple cell lines using in vitro assay systems, performing in vivo anti-RSV evaluation of ZX-2187P, conducting experiments to elucidate the mechanism(s) of action of ZX-2187P and performing extraction, fractionation and purification of ZX-2187P to identify pure compound(s). PROPOSED COMMERCIAL APPLICATIONS: RSV is a major virus pathogen of infants and young children, an important cause of disease in adults and is responsible for a significant amount of morbidity and mortality in the elderly. No vaccines are available and the combination of ribavirin and immunoglobulin approved for use is expensive and difficult to administer. Thus, any new agent(s), which can control RSV infection, has a huge economical impact.