title: Impact of culture media and sampling methods on Staphylococcus aureus aerosols.
abstract: Staphylococcus aureus has been detected indoors and is associated with human infection. Reliable quantification of S. aureus using a sampling technique followed by culture assay helps in assessing the risks of human exposure. The efficiency of five culture media and eight sampling methods in recovering S. aureus aerosols were evaluated. Methods to extract cells from filters were also studied. Tryptic soy agar (TSA) presented greater bacterial recovery than mannitol salt agar (MSA), CHROMagar staph aureus, Chapman stone medium, and Baird-Park agarose (P < 0.05). Moreover, 93 ± 2%-95 ± 2% and 42 ± 1%-49 ± 2% of S. aureus were, respectively, recovered by a 15-min heating of gelatin filters and 2-min vortex of polycarbonate (PC) filters. Evaluation of two filtration (IOM with gelatin filter and cassette with PC filter), two impaction (Andersen 1-STG loaded with TSA and MSA) and four impingement methods [AGI-30 and BioSampler filled with Tween mixture (TM) and phosphate-buffered saline (PBS)] revealed the BioSampler/TM performed best over 30 and 60 min of sampling (P < 0.05), while low recovery efficiencies were associated with the IOM/gelatin, cassette/PC, and AGI-30/PBS combinations (P < 0.05). In addition to BioSampler/TM, collecting S. aureus onto TSA from the Andersen 1-STG is also recommended, as it is the second best method at the 60-min sampling (P < 0.05).
authors.affiliation: Institute of Environmental Health, College of Public Health, National Taiwan University, Taipei, Taiwan.|Center for Research on Environmental and Occupational Health, National Taiwan University, Taipei, Taiwan.|Research Center for Genes, Environmental and Human Health, National Taiwan University, Taipei, Taiwan.
authors.forename: C-W
authors.initials: CW
authors.lastname: Chang
authors.affiliation: Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, Taipei, Taiwan.
authors.forename: L-J
authors.initials: LJ
authors.lastname: Wang
mesh_terms: D000336:Aerosols; D061808:Air Filters / Q000382:microbiology; D000391:Air Microbiology; D003470:Culture Media; D004784:Environmental Monitoring / Q000379:methods*; D013211:Staphylococcus aureus / Q000302:isolation & purification*
chemical_list: D000336:Aerosols; D003470:Culture Media
keywords: Andersen; BioSampler; Cassette; Culture media; IOM; Staphylococcus aureus