Comparison of Abbot ID Now Method with Eurobioplex RT-PCR SARS-Cov-2 Multiplex Method for Detection of SARS-Cov-2 from Nasopharyngeal and Oropharyngeal Samples

Background: COVID 19 created an urgent demand for rapid diagnosis to encircle this pandemic and improve patient management. In this context, we evaluated the concordance of the ID NOW test compared to the Eurobioplex RT-PCR test in the rapid diagnosis of SARS-CoV-2. Methods: To evaluate the concordance of the assay at different viral loads, 154 positive samples were selected to represent the full range of Ct values observed on the Eurobioplex RT-PCR assay, ranging from 14 to 38 cycles. Positive concordance for the ID Now assay was calculating dusing Eurobioplex RT-PCR as the reference test. An additional 70 negative samples were selected to assess negative concordance. Results: Compared to Eurobioplex RT-PCR, the overall positive agreement was 79% with ID Now. Negative agreement was 100% for ID Now. ID Now showed 100% positive agreement for medium and high viral concentrations (Ct value <30). However, for Ct values >30, the positive agreement was 33.3% for ID Now. Conclusions: This study shows a major limitation of ID Now for specimens collected in universal transport media with lower viral concentrations. Further studies are necessary to evaluate the performance of ID Now for dry nasopharyngeal swabs (manufacturer's recommended method).