Project description:We compared the performance of ID NOW™ COVID-19 assay nasal swabs with RT-PCR of nasopharyngeal swabs for SARS-CoV-2 in an outbreak setting, determining whether addition of RT-PCR of residual nasal swabs (rNS) (post ID NOW™ elution) would increase overall analytic sensitivity. Devices were placed at 2 long term and 1 acute care sites and 51 participants were recruited. Prospective paired nasopharyngeal and nasal samples were collected for RT-PCR and ID NOW™. ID NOW™ had a positive and negative categorical agreement of 86% and 93% compared to RT-PCR of nasopharyngeal swabs. Sensitivity and specificity of the ID NOW™ was 86% and 100%, positive and negative predictive value was 100% and 95% (COVID-19 positivity rate: 8%). Addition of rNS RT-PCR increased the positive and negative categorical agreement to 93% and 97%. Based on these results, we propose an alternative workflow which includes complementary testing of rNS on a secondary assay.
Project description:BackgroundDecisions to isolate patients at risk of having coronavirus disease 2019 (COVID-19) in the emergency department (ED) must be rapid and accurate to ensure prompt treatment and maintain patient flow whilst minimising nosocomial spread. Reverse transcription polymerase chain reaction (RT-PCR) assays are too slow to achieve this, and near-patient testing is being used increasingly to facilitate triage. The ID NOW severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) assay is an isothermal nucleic acid amplification near-patient test which targets the RNA-dependent RNA-polymerase gene.AimTo assess the diagnostic performance of ID NOW as a COVID-19 triage tool for medical admissions from the ED of a large acute hospital.MethodsAll adult acute medical admissions from the ED between 31st March and 31st July 2021 with valid ID NOW and RT-PCR results were included. The diagnostic accuracy of ID NOW [sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV)] was calculated against the laboratory reference standard. Discrepant results were explored further using cycle threshold values and clinical data.FindingsTwo percent (124/6050) of medical admissions were SARS-CoV-2 positive on RT-PCR. Compared with PCR, ID NOW had sensitivity and specificity of 83.1% [95% confidence interval (CI) 75.4-88.7] and 99.5% (95% CI 99.3-99.6), respectively. PPV and NPV were 76.9% (95% CI 69.0-83.2) and 99.6% (95% CI 99.5-99.8), respectively. The median time from arrival in the ED to ID NOW result was 59 min.ConclusionID NOW provides a rapid and reliable adjunct for the safe triage of patients with COVID-19, and can work effectively when integrated into an ED triage algorithm.
Project description:Rapid and accurate diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is essential to prevent the spread of the virus. We investigated the diagnostic accuracy of the Xpert Xpress and the ID NOW assays for rapid detection of SARS-CoV-2 using a systemic review and meta-analysis approach. A systematic literature search was performed using PubMed, Embase, and the Cochrane COVID-19 Study Register. The sensitivity and specificity of these tests for detecting viruses in patients with suspected SARS-CoV-2 infection were pooled. We used commercial and laboratory-developed reverse transcription-polymerase chain reactions as reference standards. The Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess the risk of bias. We identified 11 studies involving 1734 subjects for the Xpert Xpress assay and 10 studies involving 1778 subjects for the ID NOW assay. The pooled sensitivity and specificity of the Xpert Xpress assay for detection of SARS-CoV-2 were 0.99 (95% confidence interval [CI], 0.97 to 0.99) and 0.97 (95% CI, 0.95 to 0.98), respectively. The pooled sensitivity and specificity of the ID NOW assay were 0.79 (95% CI, 0.69 to 0.86) and 1.00 (95% CI, 0.98 to 1.00), respectively. The studies included in our analysis seemed to have low methodological quality. The Xpert Xpress assay showed excellent diagnostic accuracy for rapid detection of SARS-CoV-2. However, as the ID NOW assay showed relatively low sensitivity, this test might miss several positive samples.
Project description:BackgroundThe SARS-CoV-2 pandemic has created an urgent and unprecedented need for rapid large-scale diagnostic testing to inform timely patient management. However, robust data are lacking on the relative performance of available rapid molecular tests across a full range of viral concentrations.ObjectiveThis study aimed to compare two recently-authorized rapid tests, Cepheid Xpert Xpress SARS-CoV-2 and Abbott ID Now SARS-CoV-2, to the Roche cobas SARS-CoV-2 assay for samples with low, medium, and high viral concentrations.Study designA total of 113 nasopharyngeal swabs from remnant patient samples were tested, including 88 positives spanning the full range of observed Ct values on the cobas assay.ResultsCompared to cobas, the overall positive agreement was 73.9% with ID Now and 98.9% with Xpert. Negative agreement was 100% and 92.0% for ID Now and Xpert, respectively. Both ID Now and Xpert showed 100% positive agreement for medium and high viral concentrations (Ct value <30). However, for Ct values >30, positive agreement was 34.3% for ID Now and 97.1% for Xpert.ConclusionsWhile Xpert showed high agreement with cobas across a wide range of viral concentrations, this study highlights an important limitation of ID Now for specimens collected in viral or universal transport media with low viral concentrations. Further studies are needed to evaluate the performance of ID Now for direct swabs.
Project description: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.
Project description:BACKGROUND:The SARS-CoV-2 pandemic caused a major surge in needed diagnostic capacity. In response, many EUA assays have become available for clinical laboratories, and more recently, the point of care device, Abbott ID NOW. OBJECTIVES:To determine the analytical performance of the ID NOW assay for detecting SARS-CoV-2. STUDY DESIGN:Residual NP samples collected in viral transport media were tested by the ID NOW platform in two independent laboratories. Results were compared to either the CDC or New York EUA assays, which served as reference methods. RESULTS:Overall agreement of ID NOW was 78.7%. Sensitivity was 71.7% and specificity was 100%. Notably, all false-negative results correlated to those samples that were weakly positive. CONCLUSIONS:ID NOW performs well for strong and moderately positive samples but has reduced sensitivity for weakly positive samples. This sensitivity, among other concerns, should be taken into consideration when using this test for patients with a low suspicion for COVID-19 disease.
Project description:The Abbott ID Now COVID-19 assay is a point-of-care molecular diagnostic tool for the detection of SARS-CoV-2. We prospectively monitored implementation of the assay in a tertiary care hospital emergency department (ED) for the diagnosis of early symptomatic patients. A total of 269 paired nasopharyngeal swabs were tested in parallel with the ID Now and laboratory-based molecular methodologies, 191 of which met selection criteria for testing based on symptoms description and duration. Forty-six and 48 samples were positive for SARS-CoV-2 with the ID Now and reference molecular assays respectively. Percent positive and negative agreement were high (93.8% and 99.6% respectively), as were the sensitivity and specificity (93.8% and 99.5%). ID Now results were available 17.47 hours earlier than qRT-PCR. In symptomatic patients seen in ED within 7 to 10 days of symptoms onset, the ID Now COVID-19 assay allows for rapid and accurate detection of infection.
Project description:ObjectiveDiagnostic evaluation of the ID NOW coronavirus disease 2019 (COVID-19) assay in various real-world settings among symptomatic and asymptomatic individuals.MethodsDepending on the setting, the ID NOW testing was performed using oropharyngeal swabs (OPSs) taken from patients with symptoms suggestive of COVID-19, asymptomatic close contacts, or asymptomatic individuals as part of outbreak point prevalence screening. From January to April 2021, a select number of sites switched from using OPS to combined oropharyngeal and nasal swab (O + NS) for ID NOW testing. For every individual tested, two swabs were collected by a health care worker: one swab (OPS or O + NS) for ID NOW testing and a separate swab (OPS or nasopharyngeal swab) for RT-PCR.ResultsA total of 129 112 paired samples were analysed (16 061 RT-PCR positive). Of these, 81 697 samples were from 42 COVID-19 community collection sites, 16 924 samples were from 69 rural hospitals, 1927 samples were from nine emergency shelters and addiction treatment facilities, 23 802 samples were from six mobile units that responded to 356 community outbreaks, and 4762 O + NS swabs were collected from three community collection sites and one emergency shelter. The ID NOW assay sensitivity was the highest among symptomatic individuals presenting to community collection sites (92.5%; 95% CI, 92.0-93.0%) and the lowest for asymptomatic individuals associated with community outbreaks (73.9%; 95% CI, 69.8-77.7%). Specificity was >99% in all populations tested.DiscussionThe sensitivity of ID NOW severe acute respiratory syndrome coronavirus 2 testing is the highest when used in symptomatic community populations not seeking medical care. Sensitivity and positive predictive value drop by approximately 10% when tested on asymptomatic populations. Using combined oropharyngeal and nasal swabs did not improve the performance of ID NOW assay.
Project description:PurposeHealthcare workers have experienced high levels of anxiety during the COVID-19 pandemic, particularly when caring for patients with unknown infection status. We trialled rapid preoperative point-of-care COVID-19 testing using the Abbott ID NOW™ COVID-19 for clinical validation in an urgent surgical population at a single centre in British Columbia, Canada. Here, we sought to determine the opinions and beliefs of operating room (OR) staff on the usefulness and effectiveness of point-of-care tests on workflow and wellbeing in the OR.MethodsThis descriptive study used a mixed-methods cross-sectional survey of all OR staff (nurses, anesthesiologists, surgeons, and ancillary staff) at a single centre after using the ID NOW for three months. Outcomes of interest included healthcare worker satisfaction with the ID NOW, effects on OR workflow, and worries about COVID-19 transmission.ResultsThe overall response rate was 56% (n = 133), and was highest among anesthesiologists (100%, n = 38). Respondents were satisfied with the performance of the ID NOW for rapid COVID-19 testing in preoperative patients, giving it a mean (standard deviation [SD]) rate of 4.4 [1.4] on a five-point scale. Most (115/128, 90%) recommended continued use of the ID NOW on asymptomatic patients while there are active cases of COVID-19 in the community. Respondents felt that preoperative COVID-19 testing with the ID NOW made the OR safer for staff (mean [SD] rate, 4.2 [0.8]) and patients (mean [SD] rate, 4.0 [0.9]).ConclusionDuring the COVID-19 pandemic, it is important to maintain the physical and mental wellbeing of hospital staff. Rapid point-of-care testing increased the sense of workplace safety, improved morale, and reduced worry associated with COVID-19 without excessive disruption of OR workflow.
Project description:Rapid, inexpensive, robust diagnostics are essential to control the spread of infectious diseases. Current state of the art diagnostics are highly sensitive and specific, but slow, and require expensive equipment. Here we report the development of a molecular diagnostic test for SARS-CoV-2 based on an enhanced recombinase polymerase amplification (eRPA) reaction. eRPA has a detection limit on patient samples down to 5 viral copies, requires minimal instrumentation, and is highly scalable and inexpensive. eRPA does not cross-react with other common coronaviruses, does not require RNA purification, and takes ~45 min from sample collection to results. eRPA represents a first step toward at-home SARS-CoV-2 detection and can be adapted to future viruses within days of genomic sequence availability.