Comparison of Andersen and Honey Jar Methods for Monitoring Hospital Wards

Abstract

The objective of this study was to compare the “honey jar” (HJ) sedimentation method with the reference Andersen collection method and validate this new proposed technique for performing environmental monitoring of Aspergillus in health care and other working facilities. Sterile plastic jars were left open in an operating room and adjacent rooms and replaced at weekly intervals; control jars were placed in different hospital wards. Comparison of the HJ method with the Andersen impactor sampling method showed an agreement of 70%. Interestingly, the HJ technique yielded some positive results that were not detected by the Andersen sampling method, possibly due to its continuous monitoring. A significant difference regarding the isolation of Aspergillus species in an operating theatre was found by the HJ method between the first and the second and third study phases, which correlated with the changing of air filters and refurbishment of the air conditioning system. The HJ sedimentation technique represents a valid and low cost procedure for performing environmental studies involving airborne fungi. Our results also stress the importance and need for continuous monitoring of airborne Aspergillus in critical medical environments, particularly regarding important pathogens like Aspergillus fumigatus.