FSRU, Table 1

Table 1. Results of the Evaluation of Six Hand-held Assays for the Detection of Anthrax (B. anthracis)
and Plague (Y. pestis)

Organism
Supplier
Sensitivity Specificity# Repeatability* Robustness** Stability
B. anthracis
 
Unpurified spores
Washed spores
   
No target
Target
 
1
106
108
1/30
97/99
20/20
17/20
+
 
2
105
105
10/30
86/99
18/20
17/20
+
 
3
105
106
25/30
93/99
17/20
17/20
+
 
4***
105
n.d.
7/17
21/27
n.d.
n.d.
n.d.
Y. pestis
 
37° C
25° C
 
 
 
 
 
 
5
105
n.r.
1/15
99/99
20/20
20/20
+
 
6
104
n.r.
2/15
97/99
97/99
17/20
+

<span style="font-size:10.0pt; font-family:Arial;"Times New Roman""><font face="Arial, Helvetica, sans-serif" size="2">(#) All HHAs tested positive to some degree with vegetative cells, which are the progenitor of the spores, <br /> but the results are not included in the data reported here. Also, the false-positive results obtained with <br /> interferents in the absence of target organisms are not included here. In these studies, 10<sup>7</sup> spores or cells <br /> were used.</font></span></p> <p class="MsoBodyText"><font face="Arial, Helvetica, sans-serif" size="2"><span style="font-size:10.0pt; font-family:Arial;"Times New Roman"">(*) The repeatability is the ratio of the number of sets of replicates that yielded identical results for each ticket <br /> relative to the total number of sets examined.</span></font></p> <p class="MsoBodyText"><font face="Arial, Helvetica, sans-serif" size="2"><span style="font-size:10.0pt; font-family:Arial;"Times New Roman"">(**) The robustness of the assay is reported as the number of times the HHA yielded expected results <br /> relative to the number of tests performed.</span></font></p> <p class="MsoBodyText"><font face="Arial, Helvetica, sans-serif" size="2"><span style="font-size:10.0pt; font-family:Arial;"Times New Roman"">(***) <span style="color:black">The evaluation of these HHAs was terminated midway in the project because the testing required too <br /> much total time. Each test had to be analyzed with a fluorescence reader, and only one strip could be <br /> analyzed at a time, which took 15 minutes. Thus, 10 tests would require at least 150 minutes total analysis <br /> time. In addition, if the wicking of the solution along the pad did not occur within the correct time interval, <br /> the reader automatically aborted the test. Slow wicking was observed with a number of the strips used in this <br /> study, so the experiments had to be repeated. The sensitivity of these devices was obtained from examining <br /> a series of two replicates, instead of from the stringent test.</span></span></font></p> <p class="MsoBodyText"><font face="Arial, Helvetica, sans-serif" size="2"><span style="font-size:10.0pt; font-family:Arial;color:black">(+) Stable up to </span><span style="font-size:10.0pt;font-family:Arial;"Times New Roman"">86°C</span></font></p> <p class="MsoBodyText"><font face="Arial, Helvetica, sans-serif" size="2"><span style="font-size:10.0pt; font-family:Arial;color:black">n.d. = Not determined</span></font></p> <p class="MsoBodyText"><font face="Arial, Helvetica, sans-serif" size="2"><span style="font-size:10.0pt; font-family:Arial;"Times New Roman"">n.r. = No reactivity observed</span></font></p> <p class="MsoBodyText"><font face="Arial, Helvetica, sans-serif" size="2"><a href="http://www.fbi.gov/about-us/lab/forensic-science-communications/fsc/jan2003/fsrutab1a.htm/fsru.htm#table1a"><i>Return to article.</i></a></font></p>