NCJ Number
214493
Journal
Journal of Forensic Sciences Volume: 51 Issue: 3 Dated: May 2006 Pages: 559-565
Date Published
May 2006
Length
7 pages
Annotation
This study assessed the frequency of occurrence and the composition of Bacillus species naturally present in urban aerosols in 11,059 aerosol samples from 11 U.S. cities.
Abstract
Eight of the 11 cities tested positive for Bacillus species in 50 percent or more of the samples, and the percentage of aerosol samples that contained the HD Type A group ranged from 3 percent to 32 percent. Cities from the eastern half of the United States generally had a higher frequency and broader diversity of Bacillus species than the western half of the United States. Positive sample were detected throughout the year. These environmental survey data and the genomic data illustrate the challenge of identifying specific attributes in anthrax-causing strains that are useful for forensic and surveillance detection of biothreat activity in the presence of a myriad of closely related Bacillus cereus and Bacillus thuringiensis species. When used to test for the presence of particular genes in environmental samples where many closely related species co-occur, DNA-based detection assays are an effective strategy for obtaining strong evidence of the presence of those particular genes; however, this approach cannot provide information on the individual species that are carrying those genes. For this reason, obtaining cultured isolates from the environmental sample, where many traits can be tested in a single genome, is still the standard for the accurate identification and determination of pathogenicity (disease threat). OM2.5 aerosol samples were generously provided by the U.S. Environmental Protection Agency air quality monitoring network. A total of 11,059 daily filters were obtained from 3 to 5 sampling locations in each of the cities. The description of materials and methods also addresses the DNA extraction from filters, PCR assays, and the heteroduplex assay. 2 tables, 4 figures, and 25 references