Objective: Investigation of an aspergillosis outbreak in a medical intensive care unit (RM) consists of 20 single rooms with air ?? renewal of June-August vol / h and 85% opacimetric filters. No concept of work.
Method: Patients hospitalized in RM with positive sample to Aspergillus fumigatus (Af) were included from January 2005 (cases), and considered infected (endoscopic criteria and / or histological), colonized (direct examination or 2 positive bronchial aspirates culture) or contaminated (only 1 culture).
Results: From 01/01/05 to 30/05/05, 7 cases have been identified: 1 contamination, colonization and 3 3 infections (aspergillosis tracheobronchial, all occurred in February, 2 to 3 days after admission ??, in patients with no risk factors). Despite the assumption ?? ?? an early and massive contamination, ?? Initial checks environment (air, surfaces) were negative. Contamination of mechanical ventilation equipment (fans, ?? d ?? blowing balloons) was eliminated. However, a malfunction of the flow of air in the rooms ?? was identified with falling turnover and pressures occurred in mid-January, confirmed by an expert. After the occurrence of two new cases of colonization (J8 and J14) in April-May, further investigation has enabled ?? d ?? incriminate other contributing factors: dust accumulation of reserves; décartonnage close the units; continues opening doors of rooms, units and reserves; ?? circulating air in the rooms (smoke test) which, by Venturi effect ?? ??, a dusting of vertical surfaces above the patient (positive samples). A case-study and witness ?? Other ?? environment samples suggest a risk from spontaneous / artificial ventilation sequence and proximity reserves.
Conclusions: 1) early cases occurred, making it difficult to rank for or acquired, 2) the multifactorial nature of the contamination, with seemingly decisive role of ventilation dysfunction, 3) a complex mechanism of dust concentration above patient, 4) the need for a thorough investigation ?? and coordinated decisions.
Full conference title:
- RICAI 25th (2005)