Evaluation of the FilmArray ^® system for detection of Bacillus anthracis, Francisella tularensis and Yersinia pestis

Abstract

AimsTo evaluate the sensitivity and specificity of the BioFire Diagnostics FilmArray® system in combination with their Biothreat Panel for the detection of Bacillus anthracis (Ba), Francisella tularensis (Ft) and Yersinia pestis (Yp) DNA, and demonstrate the detection of Ba spores.Methods and ResultsDNA samples from Ba, Ft and Yp strains and near-neighbours, and live Ba spores were analysed using the FilmArray® Biothreat Panel, a multiplexed PCR-based assay for 17 pathogens and toxins. Sensitivity studies with DNA indicate that the limit of detection is 250 genome equivalents (GEs) per sample or lower. Furthermore, the identification of Ft, Yp or Bacillus species was made in 63 of 72 samples tested at 25 GE or less. With samples containing 25 CFU of Ba Sterne spores, at least one of the two possible Ba markers was identified in all samples tested. We observed no cross-reactivity with near-neighbour DNAs.ConclusionsOur results indicate that the FilmArray® Biothreat Panel is a sensitive and selective assay for detecting the genetic signatures of Ba, Ft and Yp.Significance and Impact of the StudyThe FilmArray® platform is a complete sample-to-answer system, combining sample preparation, PCR and data analysis. This system is particularly suited for biothreat testing where samples need to be analysed for multiple biothreats by operators with limited training.

Clinical Evaluation of the FilmArray Blood Culture Identification Panel in Identification of Bacteria and Yeasts from Positive Blood Culture Bottles

“…There is a need for reliable, simple, and direct identification methods with short hands-on time involving limited expertise. BioFire Diagnostic's FilmArray system (FA; BioFire, Salt Lake City, UT) is a PCRbased platform developed and tested for the diagnosis of several infectious agents involved in different diseases, including respiratory viruses, Bacillus anthracis, Francisella tularensis, and Yersinia pestis (9)(10)(11). Recently, the FilmArray blood culture ID (FA BCID) panel was introduced (12).…”

Comprehensive Laboratory Evaluation of a Lateral Flow Assay for the Detection ofYersinia pestis

“…Polymerase chain reaction (PCR) assays and platforms, including the RAPID and SmartCycler, have demonstrated sensitivities of 50 fg DNA (*10 genomic equivalents, GE) for single-probe assays, 28 while the Film-Array detected Y. pestis strains at 250 to 25,000 GE. 29 Yang et al 30 investigated the use of 2 suspension arrays for the detection of Y. pestis, one of which could identify only to the genus level. The species-specific assay had a detection limit of 50 fg DNA.…”

Multiplex Detection of Three Select Agents Directly from Blood by Use of the GeneXpert System

“…The assay uses completely hands-free integrated sample processing and detection, requiring only that 1 ml of whole patient blood be added directly to the cartridge, making it ideal for point-of-care use. The United States Food and Drug Administration (FDA)-cleared FilmArray BioSurveillance system has an LOD of 250 to 2,500 CFU/ml for F. tularensis, Y. pestis, and B. anthracis (31,32), and the FDA-approved Joint Biological Agent Identification and Diagnostic System (JBAIDS), which detects individual select agent pathogens, has a limited LOD, for example, 48 copies for B. anthracis per reaction mixture. This limited LOD is the likely reason why JBAIDS assays are not recommended for direct use on whole blood.…”