AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Field Testing of Genetically Tagged Spores for Specific Detection and Tracking of Biological Simulants in the Environment
TIFFANY SUTTON, US Army Edgewood Chemical Biological Center
Abstract Number: 395 Working Group: Instrumentation and Methods
Abstract The development of spores simulant of Bacillus thuringiensis var. kurstaki (Btk) with a stable single copy of uniquely amplifiable DNA integrated into the genome provides a powerful tool for tracking the fate of biological agents that are intentionally released into the environment. The use of tailored PCR assays specific for detecting barcoded regions overcomes the ambiguity of discerning the test release material from pre-existing environmental flora or background clutter from prior releases. Here we report the testing of this new simulant in a 200 meter ambient breeze tunnel followed by a 100 gram aerosol release of a dried powder of barcoded Btk spores (BtkB) in an outdoor field in Aberdeen Proving Grounds, Edgewood, Maryland. The release of spores was imaged from a distance by a Light Detection and Ranging (LIDAR) laser system that tracked the cloud by first detecting a large biological particulate intake followed by automated immunological detection transmitted to a command post. Multiple sampling units were arrayed on the proving grounds and tested immediately following the release followed by additional testing over a two week period. An unambiguous genetic identification of the BtkB spores at Day 1 correlated with the cloud track predicted by prevailing winds, and was supported by data tracks provided by the LIDAR system. The number of collection devices with positive response diminished significantly by Day 4 to a single response down from the five collection systems that had previously responded on Day 1. The field was then agitated by a leaf blower in a fifty foot swath in an attempt to instigate re-aerosolization of the settled spores. Re-aerosolization was observed with four collections systems registering detection events. This data is in agreement with controlled studies conducted on seeded tiles set in an ambient breeze tunnel which clearly demonstrated a gradual spread of biological contamination.