Nationwide, first responders regularly encounter suspicious materials that might be biological threat agents. Routine training and process evaluations help ensure operators, technologies, and workflows are working properly within the concept of operations (ConOps) (Fig 1).
In July 2015, suitability of the yeast material was demonstrated in Operation Vigilant Sample (OVS) IV, a functional field exercise led by Captain Bryon Marsh (Georgia National Guard 4th Civil Support Team (CST)) at the Guardian Centers, Perry, GA. Local responders, state public health laboratories, CSTs, Environmental Protection Agency (EPA), and BioWatch applied state response plans in a biothreat scenario (putative Yersinia pestis).
The CSTs deposited the yeast material onto stainless steel coupons (Fig. 2) that were then placed at pre-determined locations around the training site. Sampling teams received just-in-time training and collected samples from the coupons (Fig. 3).
Mobile and public health laboratories successfully detected the yeast via quantitative polymerase chain reaction in samples from yeast-inoculated but not blank coupons.
S. cerevisiae NE095 challenged the entire assessment process, from sample to answer, including results interpretation and reporting, and enabled exercise participants to demonstrate their ability to assess a biological material in the field while minimizing health and safety risks.
Department of Homeland Security (DHS) Science and Technology Directorate funded this work under Interagency Agreement HSHQPM-14-X-00078 with NIST.
 Da Silva SM, Vang LK, Olson ND, Lund SP, Downey AS, Kelman Z, Salit ML, Lin NJ, Morrow JB. Evaluation of microbial qPCR workflows using engineered Saccharomyces cerevisiae. Biomolecular Detection and Quantification. 2016, 7:27-33. doi:10.1016/j.bdq.2016.01.001