Critique of Test Methodologies for Biological Agent Detection and Identification Systems for Military and First Responders
Abstract
Currently evaluations of the performance of various BW agent rapid detection or identification systems have primarily focused on defined aerosol samples released under favorable, controlled conditions or controlled samples assayed under laboratory conditions. Although these methods may provide information on the sensitivity, cross-reactivity, and some interferences, they may not provide sufficient information to adequately determine the effectiveness of the technology in the field conditions or when difficult environmental samples are analyzed. Results with three different technologies currently utilized by various agencies in the field (Colloidal Gold-Hand Held Assays, generic DNA, and Luminescence) have demonstrated significant performance differences when evaluated with common environmental samples. Adulterants or interfering substances, which may be used by a terrorist, have also been tested, demonstrating additional potential problems. In this study, salt, sugars, detergents, talc, phosphates, cross-reacting organisms (Bacillus spp), non-toxic material of biological origin (cereal), as well as very high concentrations of the specific organisms, were used to challenge the technologies. The purpose was to develop methods to determine both interference and potential pro-zoning issues. Results indicated that some of the immunological assays, including Anthrax, can give false positive results when a sample with high pH or ionic strength (salts) were evaluated. Moreover, a very high concentration of the antigen in a positive sample may cause a false negative result.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2002
- Accession Number
- ADA436075
Entities
People
- David Trudil