Evaluation of BioStar (R) FLU OIA (R) assay for rapid detection of influenza A and B viruses in respiratory specimens

Background: Demand for the rapid diagnosis of influenza infections has incr eased with the advent of the availability of neuraminidase antiviral therap y for influenza A and B. Several rapid assays that detect both influenza A and B are now available. Objectives: In this study we compared the performa nce of the BioSta(R) FLU OIA(R) assay to Bartels Viral Respiratory Screenin g and Identification Kit (Bartels Inc., Issaquah, WA), and cell culture. St udy design: A total of 145 patient specimens for influenza virus detection submitted in either viral transport medium or in sterile containers were ev aluated by the three methods. Specimen types included nasal washings, nasal swabs, sputum, throat swabs, and bronchial alveolar lavage (BAL) fluids. R esults: Fifty six positive specimens were identified based on culture and/o r DFA. Of these, 30 specimens were positive by the OIA assay for an overall sensitivity of 54%. The OIA assay detected 48% (n = 21) of the 44 culture positive specimens and 81% (n = 29) of the 36 DFA positive specimens. Eight y six of the 89 culture/DFA negative samples were negative by the OIA assay (97% specificity). Analysis of the OIA assay sensitivity from samples subm itted in M4 transport medium or in sterile containers revealed that M4 tran sport medium does not reduce the sensitivity of the OIA assay. Fifteen of t he 27 positive samples submitted in M4 transport medium were positive by th e OIA assay (56% sensitivity) compared to 15 of 29 positive samples transpo rted in sterile containers (52% sensitivity). Twelve specimens were either culture and/or DFA positive for viruses other than influenza, but negative by the OIA assay, suggesting that there was no cross reactivity of the OIA assay with the other virus types recovered in this study. Conclusions: The overall excellent specificity of the BioStar(R) FLU OIA(R) allows for treat ment of positive patients for influenza, however, a negative result should be confirmed by DFA and culture. (C) 2000 Published by Elsevier Science B.V . All rights reserved.