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Bioaerosol Exposure to Filtering Facepiece Respirators in a Clinical Environment (Author's Final Manuscript)

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OSTP Journal Article

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Applied Research Associates Panama City United States

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Nosocomial infections affect 5-10 percent of hospital admissions and pose a significant threat to healthcare workers HCWs. Evolving antibiotic resistance of virulent and commensal strains is leading to more severe hospital-acquired infections. This study evaluated bioaerosol contamination of filtering facepiece respirators FFRs worn by hospital staff. Such data are needed to understand respiratory hazards for HCWs and the amount of contamination found on FFRs. Hospital environmental staff wore 3M1860 or 3M1870 FFRs during cleaning of discharged patient rooms. Coupons were cut from the FFRs, then the external and filtering layers were extracted. Extracts were plated on permissive media and all colonies were counted. 1.6 percent of isolates were characterized by biochemical and antimicrobial resistance testing using vancomycin and oxacillin. Average loading of microbes ranged from 6.2 x 102 -4.8 x 103 colony-forming units per mask. 97 percent of the contamination was found on the external layer. Most of the isolates recovered were coagulase-negative, Gram-positive staphylococci and Micrococcus spp . 73 percent of the Gram-positive and 67 percent of the Gram-negative isolates were resistant to oxacillin. Vancomycin resistance was lower --9.2 percent and 36.7 percent, respectively. Our data confirm the presence of antibiotic-resistant microorganisms in hospital air, and the attendant threat to hospital occupants. An estimate is provided for mask bioburden loading that can be used to refine FFR reuse strategies.

Subject Categories:

  • Microbiology
  • Medical Facilities, Equipment and Supplies

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