Fast and reliable real life data on COVID-19 triaging with ID NOW

In the context of SARS-CoV-2 pandemic, rapid and easy-to-perform diagnostic methods are essential to limit the spread of the virus and for the clinical management of COVID-19 patients. Although real-time polymerase chain reaction remains the “gold standard” to diagnose acute infections, this technique is expensive, requires trained personnel, well-equipped laboratory and is time-consuming. A prospective evaluation of the Abbott ID NOW COVID-19 point-of-care testing that uses isothermal nucleic acid amplification for the qualitative detection of SARS-CoV-2 RdRp gene was run in the Emergency Department during the third wave of COVID-19 pandemic. ID-NOW significantly simplified SARS-CoV-2 identification and COVID-19 patient triaging, being highly valuable in rapidly locating febrile patients in or out of COVID-19 areas, and can be considered as a first-line diagnostic test in the Emergency Room setting.


a b s t r a c t
In the context of SARS-CoV-2 pandemic, rapid and easy-to-perform diagnostic methods are essential to limit the spread of the virus and for the clinical management of COVID-19 patients. Although real-time polymerase chain reaction remains the "gold standard " to diagnose acute infections, this technique is expensive, requires trained personnel, well-equipped laboratory and is time-consuming. A prospective evaluation of the Abbott ID NOW COVID-19 point-of-care testing that uses isothermal nucleic acid amplification for the qualitative detection of SARS-CoV-2 RdRp gene was run in the Emergency Department during the third wave of COVID-19 pandemic. ID-NOW significantly simplified SARS-CoV-2 identification and COVID-19 patient triaging, being highly valuable in rapidly locating febrile patients in or out of COVID-19 areas, and can be considered as a first-line diagnostic test in the Emergency Room setting.
In the context of SARS-CoV-2 pandemic, febrile patients admitted to Emergency Departments (ED) require a prompt identification of SARS CoV-2 for immediate entry to care. Polymerase chain reaction (PCR)-based molecular testing is expensive and not feasible without expertise and a well-equipped laboratory, often with considerable turnaround times for final results. Rapid antigen-based tests for SARS-CoV-2 are inexpensive, can return results within 15 min ( https://www.cdc.gov/coronavirus/2019ncov/lab/resources/antigen-tests-guidelines.html ) and have received Food and Drug Administration (FDA) an CE Emergency Use Authorization (EUA) within the first 5-12 days after symptom onset but test performance have shown poor sensitivity and specificity [ 1 , 2 ]. Therefore new rapid molecular tests are highly desirable and of value for the fast triaging of symptomatic patients during the peak of the pandemic.
ID NOW COVID-19 assay (Abbott Molecular Diagnostics, Des Plaines, IL, USA) has recently proved a simple, rapid, specific and sensitive diagnostic tool for the early detection and identification of SARS-CoV-2 [3][4][5][6] . In addition to clinical laboratories, this assay can be performed by trained non-laboratory personnel in patient care settings such ED. The test uses the isothermal nucleic acid amplification technology for qualitative detection of a SARS-CoV-2 unique region of the RdRp gene segment with a manufacturer's claimed lower limit of detection of 125 genome equivalents/ml. Fluorescently labeled molecular beacons are used to specifically identify each of the amplified RNA targets including an internal control. ID NOW COVID-19 test circumvent limitations of ID-NOW positive and negative predictive values for the identification of SARS-CoV-2 were 100% and 95.9%, respectively. Discordant ID-NOW-negative/RT-PCR positive samples were resolved with Xpert Xpress SARS-CoV-2 (Cepheid, Sunnyvale, CA, USA) assay, confirming that these were all weak positive, with a mean cycle threshold (C t ) across N and E genes ≥ 35 (C t range 35-38) suggesting that they had a low SARS-CoV-2 RNA concentration. The rate of invalid ID NOW was 2% ( n = 3) at first testing, decreasing to 0% after test repetition, that was done immediately.
In conclusion, the real-life results of this study are in line with others [3] suggesting that ID NOW significantly simplified the diagnostic process of COVID-19 triaging of febrile patients admitted to ED during the pandemic. Patients admission was faster with a more accurate triaging.
Based on our experience, ID NOW is a useful rapid rule-out testing for COVID-19 in patients with acute respiratory symptoms admitted to ED, allowing a sensitive and specific diagnosis of COVID-19 with a fast turn-around-time as required by the pandemic in the emergency setting.

Declaration of Competing Interest
None declared.

Funding source
None.