Requirements for Biological Threat Identification Systems

Rapid identification of bioterrorism or biological warfare agents is most urgent within the first 24 h after an attack (1–3). After that period, the ability to affect the prognosis of patients that have been infected with a highly virulent organism, such as Bacillus anthracis, sharply declines (2). For less virulent organisms, identification during the pre-symptomatic stage is critical because the clinical picture is often confusing. Some patients may present with “flu-like” symptoms, rash or unusual skin lesions, respiratory or gastrointestinal illness (1,4–5). Definitive identification of biological threats requires an integrated approach (see Fig. 1). No single identification technology is sufficient to definitively identify biological threats because of the microbial diversity, an often confusing clinical presentation, the close antigenic and genetic relatedness of some biological agents (see Table 1) and the consequences of misidentification (1,4–8). A system of overlapping technologies and approaches are required to achieve the highest level of confidence and decrease the number of “false alarms” (9). The Food and Drug Administration (FDA) has not reviewed the performance of many technologies proposed for the rapid identification of biological threat agents. All identifications must be confirmed by using “gold standard” or FDA-approved methods, such as bacterial culture. In the future, first responders, medical care providers, and laboratories will need a combination of overlapping diagnostic approaches tied together by a robust information management system when responding to a bioterrorism attack (9).