2001 Volume 75 Issue 9 Pages 792-799
We have evaluated a new rapid detection kit for influenza A and B viruses, known as the Quick Vue Influenza test (Quidel Coporation, USA); which is based on immunochromatography using virus isolates and clinical specimens.
Twelve strains of influenza A and B were tested for evaluate the reactivity and detection limits of this test. The Quick Vue Influenza test showed a positive result for all twelve strains of influenza virus and a negative result for fourteen different kinds of other respiratory viruses. The detection limits for six strains were 5 to 30 pfu/ml for a cell culture, 1.0×103 to 6.0×104pfu/ml for 1st PCR, 1 to 50pfu/ml for nested PCR, 3.0×105 to 6.0×105pfu/ml for the Quick Vue Influenza test, 1.5×105 to 1.0×106 pfu/ml for the Directigen Flu A, and 7.5×105 to 5.0×106pfu/ml for the FLU OIA.
Furthermore, the Quick Vue Influenza test were clinically evaluated using 92 throat swab specimens collected from patients with influenza-like illnesses.
By cell culture, influenza viruses were detected in 49 of the 92 specimens (AH1N1: 20, AH3N2: 7, B: 22); the titers of the influenza viruses were between 2.5pfu/ml and 7.0×105pfu/ml. Compared to cell culture, the Quick Vue Influenza test showed a sensitivity of 75.5%, a specificity of 93.0%, a positive predictive value of 92.5%, a negative predictive value of 76.9%, and an efficiency value of 83.7%. On the other hand, influenza viruses were detected in 54 of the 92 specimens (AH1N1: 19, AH 3N2: 10, B: 25) by RT-PCR. Compared to RT-PCR, the Quick Vue Influenza test showed a sensitivity of 72.2%, a specificity of 97.4%, a positive predictive value of 97.5%, a negative predictive value of 71.2%, and an efficiency value of 82.6%. Overall, only one throat swab specimen produced a false positive result using the Quick Vue Influenza test; thus, this test appears to have a high specificity.
We conclude that the Quick Vue Influenza test is a simple one-step test with a sensitivity and specificity equivalent to those of other conventional diagnostic kits. The test is useful and suitable for the diagnosis of influenza and for identifying influenza patients requiring antiviral therapy.
