Summary:Oncology ward over a 14-day period in February 1997. Five had upper respiratory tract infection (URTI) and three had LRTI (see Table 1). Of three patients with LRTI, two Respiratory syncytial virus (RSV), a common cause of both upper and lower respiratory tract infection (LRTI)were BMT recipients. One patient was 6 weeks post-PBSC allograft for AML and was admitted with a 24-h history of in infants and children, is rarely described as an infective agent in adults. It has been reported in bone mara respiratory illness. The other transplant recipient with LRTI was 4 years post-allogeneic BMT for CML. This row transplant (BMT) recipients and patients with malignancy immunosuppressed by chemotherapy. Such patient, already an inpatient with a febrile illness, was on broad-spectrum antibiotics (piperacillin, gentamicin) and reports are often associated with a high mortality. We report an outbreak of RSV infection which occurred antifungal therapy (amphotericin 1 mg/kg). Both were on cyclosporin A and the latter patient was also on steroids predominantly in BMT recipients in which early investigation and institution of ribavirin therapy resulted in and azathioprine for chronic graft-versus-host disease. RSV LRTI also developed in a patient who was severely neuall patients making a full recovery. Keywords: respiratory syncytial virus; BMT recipients; tropenic (neutrophils Ͻ0.2 × 10 9 /l) secondary to induction chemotherapy for AML. This patient was receiving broadribavirin spectrum antimicrobials for suspected pulmonary fungal infection (piperacillin, gentamicin, vancomycin and amphotericin 1 mg/kg) although this was not proven. All with Respiratory syncytial virus (RSV) is a common cause of LRTI complained of breathlessness, had inspiratory both upper and lower respiratory tract infection (LRTI) in crackles on chest auscultation and reduced oxygen satuinfants and children, particularly in winter. RSV LRTI is ration on air (SaO 2 Ͻ 90%). Two demonstrated abnormal rarely described in adults, although it has been reported changes on CXR (left lower zone shadowing in one patient in bone marrow transplant (BMT) recipients, solid organ and bilateral lower zone shadowing in the other), although transplant recipients, and patients with malignancy one hypoxic patient had no focal abnormality on CXR. All immunosuppressed by chemotherapy. 1-7 Previous reports of three patients with LRTI underwent bronchoscopy with RSV pneumonia occurring in BMT recipients or patients broncho-alveolar lavage. RSV was detected by direct with acute leukaemia show a high mortality. 1,2 This high immunofluorescence of bronchial washings using a fluormortality may relate to delays in diagnosis and treatment escein-labelled antibody technique. In light of the cases of of the disease. Ribavirin, an antiviral agent used in the treat-RSV LRTI, all patients (inpatients and outpatients attending ment of RSV infection in infants and children, has been the unit) were screened for RSV if they had respiratory used with some success in immunocompromised a...