Biological Aerosol Sentry and Information System (BASIS)

BASIS is a detect-to-treat technology. That is, it's designed to detect and locate an aerosol release of a biothreat organism quickly and accurately enough for an effective response. For example, the survival rate from exposure to the anthrax bacterium is high when antibiotic therapy can be administered before symptoms appear, but after symptoms manifest, the survival rate diminishes significantly.

BASIS collects air samples at well-defined locations and at specified time intervals to help determine both the time and place of the release. Its mobile field laboratory rapidly tests samples for evidence of potentially lethal bacteria and viruses. Safeguards built into the system ensure a sample's integrity. Aerosol releases of bacteria or viruses tend to quickly become diluted as their distance from the release site increases. BASIS is designed with extremely high sensitivity for detecting the most likely threat pathogens. By identifying a pathogen within hours, BASIS allows medical response units to mobilize while law-enforcement agencies begin the search for terrorists.

BASIS is designed for indoor or outdoor use at high-visibility events or around likely terrorist targets. In 2001, the technology was successfully tested with live microbes inside a sealed chamber at the U.S. Army's Dugway Proving Ground. BASIS was first deployed in the month following the September 11 terrorist attacks. It was also deployed in Salt Lake City, Utah, for the 2002 Winter Olympic Games. During the Olympics, BASIS operated for 35 days at sports venues, urban areas, and transportation hubs. In all, 2,200 air samples were analyzed. BASIS was later deployed in Albuquerque during the summer of 2002 and in New York City for the first anniversary of 9/11.

BASIS includes three major components. Aerosol collection hardware continually collects, time-stamps, and stores samples. A mobile field laboratory analyzes DNA from the samples and can identify and characterize a threat organism in less than half a day with a virtually zero false-alarm rate. Software designed by the BASIS team controls and integrates the operations.

The air samplers, called distributed sampling units (DSUs), suction air through filters that have microscopic-size pores and collect any regional microbes onto the filters' surface. DSUs can be deployed indoors, for example, at sports arenas or airline terminals or within heating and air-conditioning systems, and outdoors at airport drop-off areas, urban commercial centers, bridges, tunnels-any area with a significant threat of bioterrorism. DSUs are locked and password-protected to prevent unauthorized access and to guarantee the integrity of filters.

A semi-automated mobile field laboratory analyzes each filter, searching for DNA from target pathogens-those organisms identified by the CDC as high-priority threat agents. Inside the field lab, DNA is amplified via the polymerase chain reaction (PCR), a quick, reliable method for detecting DNA of specific microbes. Should a target pathogen be present, PCR amplifies its DNA while ignoring DNA from other microbes.

To confirm a positive finding and identification of the organism, the laboratory analyzes the target sample a second time. The characterization is so precise that a microbe can often be identified down to the strain level. The suspect DNA can then be sequenced to determine if genetic engineering has, for example, increased a microbe's virulence or has in any way engendered drug resistance. When a positive identification has been confirmed, the field lab immediately notifies the appropriate response agencies. The entire process-from collecting samples to identifying a threat organism-typically requires only 8 to 10 hours.