New Way to Test Airborne Pathogen Sensors Slated for BioWatch Program

The test and evaluation community for the past 70 years has used one method to find out whether sensors designed to detect weaponized pathogens work as advertised.

It is not a simple task. One can’t walk out into a field and release live anthrax spores into the air. That would obviously endanger anyone nearby.

“It is ethically impermissible. It’s dangerous and puts people at risk,” said Henry Gibbons of the Army Edgewood Chemical Biological Center’s biosciences division.

The center is developing non-pathogenic Bacillus thuringiensis simulant strains that contain unique genetic “barcodes,” or tags, to monitor how spores respond or persist in the environment.

The T&E community has had one simulant to work with since the 1940s, which limits the kind of tests that can be carried out. Spots like Dugway Proving Grounds, Utah, where it has been used for decades, already has too much of it in the environment.

“There is a lot of that stuff already out there,” Gibbons said.

Furthermore, every time there is a test, scientists have to wait for the fake pathogen to decay before proceeding to the next round. Controlling for weather is also problematic. If it changes between tests it could skew the results.

The center wants to introduce not only a new simulant, but one that has the genetic diversity to allow for multiple strains.

“Instead of releasing one thing at a time, we want to be able to release four or five things,” Gibbons said.

That will ultimately save time and money.

Edgewood settled on the widely used bacillus thuringiensis. It can be bought off the shelf at garden supply stores where it is sold for organic farming to control gypsy moths. It has a proven safety record. It also has physical properties closer to anthrax than the old simulant, Gibbons said.

The diversity is achieved through the placement of the genetic tags in the bacillus thuringiensis chromosome. That will also distinguish it from the common strain used in agriculture.

The technology will be applied to the Department of Homeland Security’s BioWatch program, which places sniffers in various U.S. cities in order to detect the release of biological weapons, as well as the Army’s Next Generation Diagnostics System, Gibbons said.

Photo Credit: Sandia National Laboratories

Topics: Chem Bio Protection, Homeland Security