RSV infections are an annually recurring problem of significant morbiditiy and mortality in the immunocompromised host, especially after lung and stem cell transplantation. The effectiveness of hygienic (isolation) and therapeutic (ribavirin, immunoglobulin, pavilizumab) measures depends of high index of suspicion and rapid diagnostic confirmation by the antigen test, PCR and/or culture. Allocation of resources require stratification of measures according to the known or estimated risk for complications.