Evaluation of the survivability of microorganisms used in breathing filters on hospital ventilators
This study assessed whether breathing filters present in ventilating machine could be a potential reservoir for the survival and growth of bacteria and mold spores.
Using a Henderson apparatus in separate experiments under controlled conditions, six different microorganisms (B. atrophaeus 10073, S. epidermidis 12721, MS-2 coliphage (virus surrogate), E. coli 9481, B. diminuta 11091 and Aspergillus brasiliensis (formerly niger) ATCC 16404) were sprayed onto membranes from breathing filters. The contaminated loaded filter membranes were then attached to an experimental rig through which clean air was drawn at a constant rate, in order to simulate the use of the membrane filter for six days. The results included:
These experiments indicate that microorganisms will survive on breathing filters used in ventilation machines. There is therefore a potential for cross infection between patients when such equipment is used.
Last reviewed: 25 October 2010