Bioaerosol exposure to personnel in a clinical environment absent patients

ABSTRACT

Nosocomial infections pose a significant and escalating threat to both patients and healthcare workers (HCWs). By their nature, hospitals induce antibiotic resistance in virulent and commensal strains, leading to increasingly severe hospital-acquired infections. This study measured environmental exposure experienced by domestic staff cleaning vacated patient rooms of a community hospital to bacteria in ambient bioaerosols. While they cleaned the room, participants wore an N95 filtering facepiece respirator (FFR), from which coupons were cut and bacteria were extracted, cultured and enumerated. Extrapolation to the full area of the respirator yielded measured exposures of 0.2–1.4 × 10⁴ colony-forming units/hour, of which ∼97% collected on the front layer of the N95, suggesting a possible role for minimal respiratory protection in nonpatient environments. Random resistance testing of 1.6% of the isolates showed that ∼70% of both Gram-positive and Gram-negative organisms exhibited resistance to oxacillin and ∼9% of the Gram-positives displayed resistance to vancomycin. These data provide an estimate for mask bioaerosol loading that can be used in risk modeling and to refine strategies for reuse of FFRs during critical shortages.

KEYWORDS:

• Antibiotic resistance
• background
• hospital
• infection
• nosocomial
• N95 respirator

Acknowledgments

This study would not have been possible without the generous cooperation of Linda Deneen and the participating staff of BMC.

Funding

This work was funded by the FDA, Centers for Devices and Radiologic Health, through an interagency agreement with the Air Force Research Laboratory.

Disclaimer

The findings and conclusions of this article are those of the authors and do not necessarily reflect the views of the FDA or of the U.S. Air Force. The mention of commercial products, their sources, or their use in connection with material reported herein is not to be construed as either an actual or implied endorsement of such products.