Evaluation of bioaerosol sampling techniques for Legionella pneumophila coupled with culture assay and quantitative PCR

Chang, Ching‐Wen; Chou, F. C.; Hung, Por‐Tying

doi:10.1016/j.jaerosci.2010.09.002

Cited by 25 publications

(23 citation statements)

References 38 publications

(65 reference statements)

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“…The parameter CS represents the colony survival rate of E. faecalis aerosols on each agar medium; isolates with higher CS values correspond to species that are more resistant to the stress of air sampling. The following levels of resistance to stress from impaction and filtration have previously been reported ( (Li and Lin 1999a,b;Li et al 2003;Tseng and Li 2005;Chang et al, 2010;Hsiao et al 2012). The CS of gram-positive E. faecalis in the present study (CS = 0.6-1.2) was much higher than those reported for S. aureus and E. coli.…”

Section: Chamber Studysupporting

confidence: 56%

Performance of CHROMagar VRE Medium for the Detection of Airborne Vancomycin-Resistant/SensitiveEnterococcusSpecies

Hsiao

Cheng

Chang

et al. 2013

Aerosol Science and Technology

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Vancomycin-sensitive and vancomycin-resistant Enterococcus (VSE and VRE) species have become a significant health problem. CHROMagar medium, which permits direct, color-based identification of target pathogens, could potentially be used to rapidly monitor airborne VSE and VRE. In this study, the efficiency of CHROMagar VRE medium without vancomycin supplementation (CVSE) for collecting airborne vancomycin-sensitive Enterococcus faecalis was evaluated in a chamber study. Subsequently, the performance of bioaerosol samplers combined with CVSE and CHROMagar VRE (CVRE) was evaluated in a hospital environment, a wastewater treatment plant, and a pig-rearing facility. Our results demonstrated that an Andersen impactor was much more effective than a Nuclepore filter for collecting airborne E. faecalis at relative humidity levels of 30% and 55%. In addition, approximately 10% of the isolated environmental Enterococcus strains were vancomycin-resistant. The average sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the colony identification were 58.5%, 81.3%, 5.5%, and 99.1%, respectively, for CVSE and 100%, 88.3%, 8.4%, and 100%, respectively, for CVRE. These findings indicate that the use of CHROMagar might provide a rapid method for detecting airborne VSE or VRE, shortening the detection time to 24-48 h. However, any mauve-colored colonies recovered on CVSE or CVRE by air sampling should be subjected to further identification tests.

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Section: Chamber Studysupporting

confidence: 56%

Performance of CHROMagar VRE Medium for the Detection of Airborne Vancomycin-Resistant/SensitiveEnterococcusSpecies

Hsiao

Cheng

Chang

et al. 2013

Aerosol Science and Technology

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“…Literature indicates the TM may help in reducing osmotic shock to bacteria and improving cell suspension in liquid (Chang et al, 2010). The PBS was the DW containing 0.82% NaCl, 0.02% KCl, 0.115% Na 2 HPO 4 , and 0.02% KH 2 PO 4 .…”

Section: Collection Fluidmentioning

confidence: 99%

Methods for quantifyingStaphylococcus aureusin indoor air

Chang

Wang

2014

Indoor Air

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Staphylococcus aureus has been detected in indoor air and linked to human infection. Quantifying S. aureus by efficient sampling methods followed by appropriate sample storage treatments is essential to characterize the exposure risk of humans. This laboratory study evaluated the effects of sampler type (all-glass impinger (AGI-30), BioSampler, and Andersen one-stage sampler (Andersen 1-STG)), collection fluid (deionized water (DW), phosphate-buffered saline (PBS), and Tween mixture (TM)), and sampling time (3-60 min) on cell recovery. Effects of storage settings on bacterial concentration were also assessed over 48 h. Results showed BioSampler performed better than Andersen 1-STG and AGI-30 (P < 0.05) and TM was superior to PBS and DW (P < 0.05). An increase in sampling time negatively affected the recoveries of cells in PBS of BioSampler and AGI-30 (P < 0.05), whereas cell recoveries in TM were increased at sampling of 6-15 min compared with 3 min. Concentrations of cells collected in PBS were decreased with storage time at 4 and 23 °C (P < 0.05), while cells stored in TM showed stable concentrations at 4 °C (P > 0.05) and increased cell counts at 23 °C (P < 0.05). Overall, sampling by BioSampler with TM followed by sample transportation and storage at 4 °C is recommended.

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“…The well-characterized swirling liquid impinger (BioSampler) was used as a reference air sampler in this study (Willeke et al 1998;Lin et al , 2000Hermann et al 2006;Rule et al 2007;Fabian et al 2009;Van Droogenbroeck et al 2009;Chang et al 2010;Kesavan et al 2010b;Chang and Chou 2011;Kesavan et al 2011). Compared to the BioSampler, the available performance data for the rest of the involved air samplers were more limited; gelatin filters (Li 1999;Lin and Li 1999;Tseng and Li 2005;Burton et al 2007;Fabian et al 2009;Van Droogenbroeck et al 2009;Chang and Chou 2011;Estill et al 2011;Zhao et al 2011), Coriolis FR (or Coriolis μ and δ) (Carvalho et al 2008;Gómez-Domenech et al 2010;Ahmed et al 2013), XMX-CV (or XMX/2L-MIL and XMX/2A) (Cooper 2010;Black 2011;Kesavan et al 2011;Black and Cooper 2012;Enderby 2012), BioCapture 650 (Kesavan et al 2011;Enderby 2012), OMNI-3000 (Kesavan et al 2011;Zhao et al 2011), SASS 2300(or SASS 2000 (Kesavan and Stuebing 2009;Kesavan et al 2011), andSASS 3100 (Kesavan et al 2010b).…”

Section: Introductionmentioning

confidence: 99%

Comparative Testing and Evaluation of Nine Different Air Samplers: End-to-End Sampling Efficiencies as Specific Performance Measurements for Bioaerosol Applications

Dybwad

Skogan

Blatny

2014

Aerosol Science and Technology

104

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Accurate exposure assessments are needed to evaluate health hazards caused by airborne microorganisms and require air samplers that efficiently capture representative samples. This highlights the need for samplers with well-defined performance characteristics. While generic aerosol performance measurements are fundamental to evaluate/compare samplers, the added complexity caused by the diversity of microorganisms, especially in combination with cultivation-based analysis methods, may render such measurements inadequate to assess suitability for bioaerosols. Specific performance measurements that take into account the end-toend sampling process, targeted bioaerosol and analysis method could help guide selection of air samplers.Nine different samplers (impactors/impingers/cyclones/ electrostatic precipitators/filtration samplers) were subjected to comparative performance testing in this work. Their end-to-end cultivation-based biological sampling efficiencies (BSEs) and PCR-/microscopy-based physical sampling efficiencies (PSEs) relative to a reference sampler (BioSampler) were determined for gram-negative and gram-positive vegetative bacteria, bacterial spores, and viruses.Significant differences were revealed among the samplers and shown to depend on the bioaerosol's stress-sensitivity and particle size. Samplers employing dry collection had lower BSEs for stresssensitive bioaerosols than wet collection methods, while nonfilterbased samplers showed reduced PSEs for 1 μm compared to 4 μm bioaerosols. Several samplers were shown to underestimate bioaerosol concentration levels relative to the BioSampler due to having lower sampling efficiencies, although they generally obtained samples that were more concentrated due to having higher concentration factors.Our work may help increase user awareness about important performance criteria for bioaerosol sampling, which could contribute to methodological harmonization/standardization and result in more reliable exposure assessments for airborne pathogens and other bioaerosols of interest.

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Evaluation of bioaerosol sampling techniques for Legionella pneumophila coupled with culture assay and quantitative PCR

Cited by 25 publications

References 38 publications

Performance of CHROMagar VRE Medium for the Detection of Airborne Vancomycin-Resistant/SensitiveEnterococcusSpecies

Performance of CHROMagar VRE Medium for the Detection of Airborne Vancomycin-Resistant/SensitiveEnterococcusSpecies

Methods for quantifyingStaphylococcus aureusin indoor air

Comparative Testing and Evaluation of Nine Different Air Samplers: End-to-End Sampling Efficiencies as Specific Performance Measurements for Bioaerosol Applications

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