Acceptable performance of the Abbott ID NOW among symptomatic individuals with confirmed COVID-19

Abstract

Introduction. The ID NOW is FDA approved for the detection of SARS-CoV-2 in symptomatic individuals within the first 7 days of symptom onset for COVID-19 if tested within 1 h of specimen collection.Gap statement. Clinical data on the performance of the ID NOW are limited, with many studies varying in their study design and/or having small sample size.Aim. In this study we aimed to determine the clinical performance of the ID NOW compared to conventional RT-PCR testing.Methodology. Adults with COVID-19 in the community or hospital were recruited into the study. Paired throat swabs were collected, with one throat swab transported immediately in an empty sterile tube to the laboratory for ID NOW testing, and the other transported in universal transport media and tested by an in-house SARS-CoV-2 RT-PCR assay targeting the E gene.Results. In total, 133 individuals were included in the study; 129 samples were positive on either the ID NOW and/or RT-PCR. Assuming any positive result on either assay represents a true positive, positive per cent agreement (PPA) of the ID NOW compared to RT-PCR with 95 % confidence intervals was 89.1 % (82.0-94.1%) and 91.6 % (85.1-95.9%), respectively. When analysing individuals with symptom duration ≤7 days and who had the ID NOW performed within 1 h (n=62), ID NOW PPA increased to 98.2 %.Conclusion. Results from the ID NOW were reliable, especially when adhering to the manufacturer's recommendations for testing.

Keywords: COVID-19 diagnostics; ID NOW; rapid SARS-CoV-2 test.

Fig. 1.

Positive per cent agreement of the ID NOW and RT-PCR from samples, stratified based on sample/individual characteristics, with 95 % confidence intervals provided. Stratified samples include those among all individuals (N=133), individuals with symptom duration >7 days (N=33), individuals with symptom duration ≤7 days (N=100), individuals who had the ID NOW performed within 1 h of collection (N=83), and individuals with symptom duration ≤7 days and ID NOW performed within 1 h of collection (N=62).