Clinical Evaluation of the ZstatFlu-II Test: a Chemiluminescent Rapid Diagnostic Test for Influenza Virus

University of Missouri - Kansas City, Kansas City, Missouri, United States
Journal of Clinical Microbiology (Impact Factor: 3.99). 08/2002; 40(7):2331-4. DOI: 10.1128/JCM.40.7.2331-2334.2002
Source: PubMed


Exploiting the high sensitivity of the chemiluminescence phenomenon, an accurate and sensitive point-of-care test, called the ZstatFlu-II test (ZymeTx, Inc., Oklahoma City, Okla.), was developed to detect influenza virus infections. The ZstatFlu-II test takes 20 min and requires approximately 2 min of "hands-on" time for operational steps. The ZstatFlu-II test does not distinguish between infections with influenza virus types A and B. ZstatFlu-II test results are printed on Polaroid High-Speed Detector Film, allowing test results to be archived. A prototype version of the ZstatFlu-II test was evaluated during the 2000-to-2001 flu season with 300 nasal aspirate specimens from children at a pediatric hospital. Compared to culture, the ZstatFlu-II test had 88% sensitivity and 92% specificity. The Directigen test had a sensitivity of 75% and a specificity of 93%. The sensitivity of the ZstatFlu-II test was significantly higher than that of the Directigen test (P < 0.0574).

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Available from: Lisa M Pence, Jul 24, 2014
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    • "However, the sensitivity estimates generated by other studies do not support this hypothesis (Yamazaki et al., 2000; Chan et al., 2002; Reina et al., 2002; Landry and Ferguson, 2003; Ruest et al., 2003; Landry et al., 2004; Alexander et al., 2005; Grondahl et al., 2005; Weinberg and Walker, 2005; Drinka 2006). Sensitivity estimates also did not vary with the type of gold standard (culture versus RT-PCR) (Yamazaki et al., 2000; Chan et al., 2002; Cazacu et al., 2003; Dunn et al., 2003; Ruest et al., 2003; Hamilton et al., 2002; Cazacu et al., 2004; Alexander et al., 2005; Grondahl et al., 2005; Weinberg and Walker, 2005 Drinka, 2006). One factor that might contribute to low sensitivity of the EIA is that the manufacturers of the EIA test specify submitting the swab specimen in 1 to 2 mL of transport medium. "
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    ABSTRACT: We describe the engineering and product development of the chemiluminescent ZstatFlu-II Test kit for influenza diagnostics. The reaction vessel is a chemical implementation device with a polystyrene bottom chamber and a polypropylene top chamber that screw together. The patient's specimen is dispersed in a proprietary diluent and mixed inside the bottom chamber with the influenza viral neuraminidase-specific substrate, 1,2-dioxetane-4,7-dimethoxy-Neu5Ac. Neuraminidase catalysis releases the dioxetane. The top chamber contains 40% NaOH and is sealed at the top with an ABS plastic plug-crush pin assembly. The top chamber floor is 85% thinner at the centre, forming a frangible flap. An automated imaging device serves as an incubator for the chemical implementation devices and also facilitates the piercing of the flap by the crush pin. This action results in NaOH flushing into the bottom chamber, initiating chemiluminescence. The imaging device also exposes the Polaroid high-speed detector film to chemiluminescence. At the end of exposure, the film is automatically processed and ejected. Chemiluminescence from an influenza virus-positive specimen produces a "+"-shaped white image, archiving the diagnostic outcome. The modular ZstatFlu-II test kit components are easily adaptable for the chemiluminescent detection of a wide range of analytes.
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