QuickVue Influenza Test for Rapid Detection of Influenza A and B Viruses in a Pediatric Population

Abstract

The performance of a lateral-flow immunoassay, the QuickVue Influenza Test, for detection of influenza A and B viruses in comparison with that of cell culture was evaluated by using nasopharyngeal aspirates, in viral transport medium, from children with respiratory tract infections. The sensitivity and specificity were 79.2 and 82.6%, respectively.Influenza virus infections in children have been associated with increased outpatient visits, admissions, and antibiotic prescriptions (4, 7). Rapid diagnostic methods would therefore be useful to prevent unnecessary antibiotics and admissions and facilitate early antiviral administration. The usual method for diagnosis of influenza virus is cell culture, a method that has good sensitivity (9) but is not very timely.A new rapid diagnostic kit (QuickVue Influenza Test; Quidel, San Diego, Calif.) using monoclonal antibodies specific for influenza A and B virus antigens is now available for direct detection from nasal swab, wash, and/or aspirate specimens. In our pediatric population, nasopharyngeal aspirates (NPA) are routinely collected for the diagnosis of viral respiratory tract infections and submitted in viral transport medium (VTM) for direct immunofluorescence assay (DFA) and cell culture.We evaluated the performance of the QuickVue Influenza Test with NPA submitted in VTM and that of the DFA and compared them with that of cell culture.Methods. NPA submitted in VTM were collected from children with respiratory tract infections seen at the Montreal Children's Hospital, Montreal, Quebec, Canada, in February and March 2001(7 weeks).Specimens received in the virology laboratory were first tested for the presence of respiratory syncytial virus (RSV; Chemicon, Chemicon International, Temecula, Calif.) and parainfluenza virus (ViraStat; ZymeTx, Oklahoma City, Okla.) by DFA. Slides were prepared for influenza A and B virus testing by DFA (Chemicon) for later reading. Specimens containing Ͻ25 cells/well by DFA were considered not interpretable but included as negative in the sensitivity and specificity calculations.Specimens were inoculated onto human embryonic lung, A549, rhesus monkey kidney, and Madin-Darby canine kidney cells. All cell lines were visually inspected every second day for a viral cytopathic effect for 16 days. Hemadsorption with washed guinea pig erythrocytes was performed on days 3, 7, 12, and 16 of incubation. Viruses isolated from cultures were confirmed by immunofluorescence on cells scraped from the monolayer.The QuickVue Influenza Test was performed on all specimens as described in the package insert. Briefly, 0.3 ml of NPA in VTM was transferred into a tube, where a test stripe was left in place for 10 min. Any shade of a pink to red test line and the appearance of a blue control line indicated a positive result for either influenza virus.All assays were run independently and read in a blinded fashion. The VTM was tested on two separate occasions by the QuickVue text and did not show any line.Results. Three hundred sixteen NPA were received. Sixte...

Comparison of the Directigen Flu A+B Test, the QuickVue Influenza Test, and Clinical Case Definition to Viral Culture and Reverse Transcription-PCR for Rapid Diagnosis of Influenza Virus Infection

“…In our study, the performance of Directigen was equivalent or superior to what has previously been described for Directigen Flu A (12,20,23,24,28,29,33) and consistent with the performance of Directigen in two previous studies with nasopharyngeal aspirates from a pediatric population (6,44). Our results are also consistent with those from previous studies of QuickVue, which reported sensitivities and specificities varying between 75 and 95% and between 76 and 93%, respectively (21,31,34,45). Our use of QuickVue within 7 days of storage at 4°C rather than within 1 h, as suggested by the manufacturer, might have affected the performance of the test but reflects the limitations of a hospital laboratory to perform tests "stat.…”

Risk Factors Associated With Severe Influenza Infections in Childhood: Implication for Vaccine Strategy

“…The sensitivity and specificity of DFA was previously assessed in our laboratory and found to be 73.6% and 98.1%, respectively. 18 Specimens were inoculated on the day they were obtained. Subtyping was not routinely done.…”

A mathematical model of lateral flow bioreactions applied to sandwich assays

“…We consider a lateral flow (LF) reactor that consists of a flat, porous membrane [9][10][11][12][13][14][15][16][17][18][19] . A schematic description of the LF reactor is diagrammed in Fig 1. A sample containing the target analytes, reporter particles, and buffer solution is introduced in a reservoir that is in contact with a dry porous membrane (typically made of nitrocellulose).…”

“…One such technique utilizes lateral-flow (LF) reactors [1][2][3][4][5][6][7][8][9][10][11][12][13][14] . There are many examples of the application of LF reactors in the health care industry.…”