title: National validation study of a cellulose sponge wipe-processing method for use after sampling Bacillus anthracis spores from surfaces.
abstract: This work was initiated to address the gaps identified by Congress regarding validated biothreat environmental sampling and processing methods. Nine Laboratory Response Network-affiliated laboratories participated in a validation study of a cellulose sponge wipe-processing protocol for the recovery, detection, and quantification of viable Bacillus anthracis Sterne spores from steel surfaces. Steel coupons (645.16 cm(2)) were inoculated with 1 to 4 log(10) spores and then sampled with cellulose sponges (Sponge-Stick; 3M, St. Paul, MN). Surrogate dust and background organisms were added to the sponges to mimic environmental conditions. Labs processed the sponges according to the provided protocol. Sensitivity, specificity, and mean percent recovery (%R), between-lab variability, within-lab variability, and total percent coefficient of variation were calculated. The mean %R (standard error) of spores from the surface was 32.4 (4.4), 24.4 (2.8), and 30.1 (2.3) for the 1-, 2-, and 4-log(10) inoculum levels, respectively. Sensitivities for colony counts were 84.1%, 100%, and 100% for the 1-, 2-, and 4-log(10) inocula, respectively. These data help to characterize the variability of the processing method and thereby enhance confidence in the interpretation of the results of environmental sampling conducted during a B. anthracis contamination investigation.
authors.affiliation: Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases, Division of Healthcare Quality Promotion, 1600 Clifton Rd., Mail-Stop C16, Atlanta, GA 30333, USA. lrose@cdc.gov
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Rose
authors.forename: Lisa
authors.initials: L
authors.lastname: Hodges
authors.forename: Heather
authors.initials: H
authors.lastname: O'Connell
authors.forename: Judith
authors.initials: J
authors.lastname: Noble-Wang
mesh_terms: D001408:Bacillus anthracis / Q000302:isolation & purification*; D001431:Bacteriological Techniques / Q000379:methods*; D004783:Environmental Microbiology; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D013171:Spores, Bacterial / Q000302:isolation & purification*; D013232:Steel; D014481:United States
chemical_list: D013232:Steel