scholarly journals A prospective diagnostic evaluation of accuracy of self-taken and healthcare worker-taken swabs for rapid COVID-19 testing

2021 ◽  
Author(s):  
Helen R. Savage ◽  
Lorna Finch ◽  
Richard Body ◽  
Rachel L. Watkins ◽  
Gail Hayward ◽  
...  
Keyword(s):  
Healthcare Worker ◽  
Diagnostic Tests ◽  
Nasal Swab ◽  
Rapid Diagnostic Tests ◽  
Absolute Difference ◽  
Accuracy Evaluation ◽  
List Type ◽  
Rt Pcr ◽  
Predictive Values ◽  
Nasal Swabs

AbstractObjectivesTo compare self-taken and healthcare worker (HCW)-taken throat/nasal swabs to perform rapid diagnostic tests (RDT) for SARS-CoV-2, and how these compare to RT-PCR. We hypothesised that self-taken samples are non-inferior for use with RDTs and in clinical and research settings could have substantial individual and public health benefit.DesignA prospective diagnostic accuracy evaluation as part of the ‘Facilitating Accelerated Clinical Evaluation of Novel Diagnostic Tests for COVID -19 (FALCON C-19), workstream C (undifferentiated community testing)’.SettingNHS Test and Trace drive-through community PCR testing site (Liverpool, UK). ParticipantsEligible participants 18 years or older with symptoms of COVID-19. 250 participants recruited; one withdrew before analysis.SamplingSelf-administered throat/nasal swab for the Covios® RDT, a trained HCW taken throat/nasal sample for PCR and HCW comparison throat/nasal swab for RDT.Main outcome measuresSensitivity, specificity, and positive and negative predictive values (PPV, NPV) were calculated; comparisons between self-taken and HCW-taken samples used McNemar’s test.ResultsSeventy-five participants (75/249, 30.1%) were positive by RT-PCR. RDTs with self-taken swabs had a sensitivity of 90.5% (67/74, 95% CI: 83.9-97.2), compared to 78.4% (58/74, 95% CI: 69.0-87.8) for HCW-taken swabs (absolute difference 12.2%, 95% CI: 4.7-19.6, p=0.003). Specificity for self-taken swabs was 99.4% (173/174, 95% CI: 98.3-100.0), versus 98.9% (172/174, 95% CI: 97.3-100.0) for HCW-taken swabs (absolute difference 0.6%, 95% CI: 0.5-1.7, p=0.317). The PPV of self-taken RDTs (98.5%, 67/68, 95% CI: 95.7-100.0) and HCW-taken RDTs (96.7%, 58/60, 95% CI 92.1-100.0) were not significantly different (p=0.262). However, the NPV of self-taken swab RDTs was significantly higher (96.1%, 173/180, 95% CI: 93.2-98.9) than HCW-taken RDTs (91.5%, 172/188, 95% CI 87.5-95.5, p=0.003).ConclusionSelf-taken swabs for COVID-19 testing offer substantial individual benefits in terms of convenience, accuracy, and reduced risk of transmitting infection. Our results demonstrate that self-taken throat/nasal samples can be used by lay individuals as part of rapid testing programmes for symptomatic adults.Trial RegistrationIRAS ID:28422, clinical trial ID: NCT04408170SummaryWhat is already known on this topic?Rapid diagnostic tests (RDTs)for SARS-CoV-2 Ag are a cheaper point-of-care alternative to RT-PCR for diagnosing COVID-19 disease.The accuracy of tests can vary dependent on sampling technique, test processing and reading of results.What this study adds?Self-taken throat-nasal swabs for RDTs can be used by symptomatic adults to give reliable results to diagnose SARS-CoV-2.Self-sampling can be implemented with little training and no assistance.

scholarly journals Integration of symptomatic, demographical and diet-related comorbidities data with SARS-CoV-2 antibody rapid diagnostic tests during epidemiological surveillance: a cross-sectional study in Jakarta, Indonesia

BMJ Open ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. e047763
Author(s):  
Rina Agustina ◽  
Ari Fahrial Syam ◽  
Fadila Wirawan ◽  
Indah S Widyahening ◽  
Ahmad Jabir Rahyussalim ◽  
...  
Keyword(s):  
Predictive Value ◽  
Diagnostic Tests ◽  
Cross Sectional Study ◽  
Rapid Diagnostic Tests ◽  
Epidemiological Surveillance ◽  
Sectional Study ◽  
Rt Pcr ◽  
Cross Sectional ◽  
Predictive Values ◽  
Current Infection

ObjectivesAffordable options for COVID-19 epidemiological surveillance are needed. Virus detection by reverse transcription-PCR (RT-PCR) is sensitive but costly, and antigen-based rapid diagnostic tests (RDTs) are cheap but with reduced sensitivity; both detect current infection but not exposure. RDT-IgM/IgG antibodies to SARS-CoV-2 detect exposure but have poor sensitivity for current infection. We investigated if the integration of symptomatic, demographical and diet-related comorbidities data with antibody RDTs improves their potential to assess infection rates in addition to exposure, thereby broadening their utility for surveillance.DesignWe conducted a cross-sectional study using data from community surveillance for SARS-CoV-2. Health workers collected nasopharyngeal swabs for RT-PCR and RDT antigen assessments and venous blood for RDT-IgM/IgG from symptomatic and asymptomatic persons. Data on age, gender, contact history, symptoms (ie, fever, cough, runny nose, sore throat, headache, dyspnoea and diarrhoea), diet-related comorbidities (ie, diabetes and hypertension) and chest radiology were collected.SettingHigh-risk communities in Jakarta, Indonesia, in May 2020.Participants343 community members’ data were included.Outcome measuresRDT-IgM/IgG sensitivity, specificity and predictive values and area under receiver operating characteristic curve for RT-PCR positivity using RDT results alone and in combination with other predictors, including symptom components derived from principal component analysis.ResultsThere were 24 PCR-confirmed infections. RDT-IgM/IgG-positive tests were associated with infection (OR 10.8, 95% CI 4.43 to 26.4, p<0.001) with an area under the curve (AUC) of 0.708% and 50% sensitivity, 91.5% specificity, 30.8% positive predictive value (PPV) and 96.1% negative predictive value (NPV). RDT results combined with age, gender, contact history, symptoms and comorbidities increased the AUC to 0.787 and yielded 62.5% sensitivity, 87.0% specificity, 26.6% PPV and 96.9% NPV.ConclusionsSARS-CoV-2 RDT-IgM/IgG results integrated with other predictors may be an affordable tool for epidemiological surveillance for population-based COVID-19 exposure and current infection, especially in groups with outbreaks or high transmission.

scholarly journals Comparing the Performance of HIV Rapid Diagnostic Tests Used in Zambia: a Systematic Review of Clinical Data.

2021 ◽  
Author(s):  
Loveness Mukuka ◽  
Andros Theo ◽  
Mowa Zambwe ◽  
Peter J Chipimo
Keyword(s):  
Systematic Review ◽  
Clinical Data ◽  
Diagnostic Tests ◽  
Rapid Diagnostic Tests ◽  
Fourth Generation ◽  
Hiv Positive ◽  
Third Generation ◽  
Predictive Values ◽  
Rapid Tests ◽  
Positive Results

Objective: To investigate the performance of the HIV RDTs used in Zambia. Method: 2,564 participants aged between 15 and 95 years from two sites in Lusaka province years were tested on OraQuick ADVANCE, Abbot Determine, and then confirmed on Uni-Gold Recombigen. The data from the participants were analyzed using SPSS version 25.0. Results: The 3 RDTs when compared to the 4th generation Abbot Architect results had the following results: OraQuick ADVANCE, Alere Determine and Uni-Gold Ultra, at 95% CI had Sensitivities of: 91.8%, 93.3% and 92.5% respectively. The specificities of OraQuick ADVANCE and Uni-Gold were the same (100.0%; 95% CI: 98.8 -100.0) but slightly different from Alere Determine (99.8%). Positive predictive values at 95% CI were 100% for OraQuick ADVANCE and Uni-Gold and 98.4% for Alere Determine. Negative predictive values (at 95% CIs) were 99.1, 99.2 and 99.1 for OraQuick ADVANCE, Alere Determine, and Uni-Gold Ultra respectively. The results showed that these RDTs could only detect 12 out of every 13 HIV positive results. Conclusion: Third generation RDTs are not effective in detecting acute positive cases. Fourth generation Rapid Tests are required to capture the positive cases being missed out.

scholarly journals Diagnostic accuracy of two commercial SARS-CoV-2 Antigen-detecting rapid tests at the point of care in community-based testing centers

2020 ◽  
Author(s):  
Alice Berger ◽  
Marie Therese Ngo Nsoga ◽  
Francisco Javier Perez-Rodriguez ◽  
Yasmine Abi Aad ◽  
Pascale Sattonnet-Roche ◽  
...  
Keyword(s):  
Diagnostic Tests ◽  
Point Of Care ◽  
Rapid Test ◽  
Diagnostic Value ◽  
Rapid Diagnostic Tests ◽  
Ease Of Use ◽  
Rt Pcr ◽  
Test Device ◽  
Community Based ◽  
Rapid Tests

AbstractBackgroundAntigen-detecting rapid diagnostic tests for SARS-CoV-2 offer new opportunities for the quick and laboratory-independent identification of infected individuals for control of the SARS-CoV-2 pandemic.MethodsWe performed a prospective, single-center, point of care validation of two antigen-detecting rapid diagnostic tests (Ag-RDT) in comparison to RT-PCR on nasopharyngeal swabs.FindingsBetween October 9th and 23rd, 2020, 1064 participants were enrolled. The Panbio™Covid-19 Ag Rapid Test device (Abbott) was validated in 535 participants, with 106 positive Ag-RDT results out of 124 positive RT-PCR individuals, yielding a sensitivity of 85.5% (95% CI: 78.0–91.2). Specificity was 100.0% (95% CI: 99.1–100) in 411 RT-PCR negative individuals. The Standard Q Ag-RDT (SD Biosensor, Roche) was validated in 529 participants, with 170 positive Ag-RDT results out of 191 positive RT-PCR individuals, yielding a sensitivity of 89.0% (95%CI: 83.7–93.1). One false positive result was obtained in 338 RT-PCR negative individuals, yielding a specificity of 99.7% (95%CI: 98.4–100). For individuals presenting with fever 1-5 days post symptom onset, combined Ag-RDT sensitivity was above 95%.InterpretationWe provide an independent validation of two widely available commercial Ag-RDTs, both meeting WHO criteria of ≥80% sensitivity and ≥97% specificity. Although less sensitive than RT-PCR, these assays could be beneficial due to their rapid results, ease of use, and independence from existing laboratory structures. Testing criteria focusing on patients with typical symptoms in their early symptomatic period onset could further increase diagnostic value.FundingFoundation of Innovative Diagnostics (FIND), Fondation privée des HUG, Pictet Charitable Foundation.

LABORATORY METHODS AND PREVALENCE OF SARS-COV-2 INFECTIONS IN THE 2ND SEMESTER OF 2021 IN THE EMERGENCY CLINICAL COUNTY HOSPITAL OF CONSTANTA

2021 ◽  
Author(s):  
Stoicescu Ramona ◽  
Stoicescu Razvan-Alexandru ◽  
Codrin Gheorghe ◽  
Schroder Verginica
Keyword(s):  
Respiratory Tract ◽  
Diagnostic Tests ◽  
Rapid Diagnostic Tests ◽  
Antigen Detection ◽  
Nucleic Acid Amplification ◽  
Rt Pcr ◽  
Laboratory Methods ◽  
Rapid Tests ◽  
Polymerase Chain ◽  
Tract Infections

"Diagnosing infections with SARS-CoV-2 is still of great interest due to the health and economic impact of COVID pandemic. The 4th wave of the COVID-19 pandemic is expected and is considered to be stronger and faster due to the dominance of Delta variant which is highly contagious [1]. SARS-CoV-2 also known as 2019-nCoV is one of the three coronaviruses (together with SARS-CoV or SARS-CoV1/Severe acute respiratory syndrome coronavirus), MERS-CoV /Middle East Respiratory Syndrome coronavirus) which can cause severe respiratory tract infections in humans [2]. Early diagnosis in COVID 19 infection is the key for preventing infection transmission in collectivity and proper medical care for the ill patients. Gold standard for diagnosing SARS-Co-V-2 infection according to WHO recommendation is using nucleic acid amplification tests (NAAT)/ reverse transcription polymerase chain reaction (RT-PCR). The search is on to develop reliable but less expensive and faster diagnostic tests that detect antigens specific for SARS-CoV-2 infection. Antigen-detection diagnostic tests are designed to directly detect SARSCoV-2 proteins produced by replicating virus in respiratory secretions so-called rapid diagnostic tests, or RDTs. The diagnostic development landscape is dynamic, with nearly a hundred companies developing or manufacturing rapid tests for SARS-CoV-2 antigen detection [3]. In the last 3 months our hospital introduced the antigen test or Rapid diagnostic tests (RDT) which detects the presence of viral proteins (antigens) expressed by the COVID-19 virus in a sample from the respiratory tract of a person. All RDT were confirmed next day with a RT-PCR. The number of positive cases detected during 3 months in our laboratory was 425. There were 326 positive tests in April, 106 positive tests in May and 7 positive tests in June. Compared with the number of positive tests in the 1st semester of 2021, the positive tests have significantly declined."

scholarly journals Point-of-Care Diagnostic Tests for Detecting SARS-CoV-2 Antibodies: A Systematic Review and Meta-Analysis of Real-World Data

2020 ◽  
Vol 9 (5) ◽  
pp. 1515 ◽  
Author(s):  
Matteo Riccò ◽  
Pietro Ferraro ◽  
Giovanni Gualerzi ◽  
Silvia Ranzieri ◽  
Brandon Michael Henry ◽  
...  
Keyword(s):  
Systematic Review ◽  
Diagnostic Tests ◽  
Large Scale ◽  
Point Of Care ◽  
Meta Analysis ◽  
Rapid Diagnostic Tests ◽  
Diagnostic Methods ◽  
Rt Pcr ◽  
Real World Data ◽  
Healthcare Facilities

SARS-CoV-2 is responsible for a highly contagious infection, known as COVID-19. SARS-CoV-2 was discovered in late December 2019 and, since then, has become a global pandemic. Timely and accurate COVID-19 laboratory testing is an essential step in the management of the COVID-19 outbreak. To date, assays based on the reverse-transcription polymerase chain reaction (RT-PCR) in respiratory samples are the gold standard for COVID-19 diagnosis. Unfortunately, RT-PCR has several practical limitations. Consequently, alternative diagnostic methods are urgently required, both for alleviating the pressure on laboratories and healthcare facilities and for expanding testing capacity to enable large-scale screening and ensure a timely therapeutic intervention. To date, few studies have been conducted concerning the potential utilization of rapid testing for COVID-19, with some conflicting results. Therefore, the present systematic review and meta-analysis was undertaken to explore the feasibility of rapid diagnostic tests in the management of the COVID-19 outbreak. Based on ten studies, we computed a pooled sensitivity of 64.8% (95%CI 54.5–74.0), and specificity of 98.0% (95%CI 95.8–99.0), with high heterogeneity and risk of reporting bias. We can conclude that: (1) rapid diagnostic tests for COVID-19 are necessary, but should be adequately sensitive and specific; (2) few studies have been carried out to date; (3) the studies included are characterized by low numbers and low sample power, and (4) in light of these results, the use of available tests is currently questionable for clinical purposes and cannot substitute other more reliable molecular tests, such as assays based on RT-PCR.

scholarly journals PREDICTIVE VALUE OF SMELL AND TASTE TEST VS PCR-RT SARS-COV-2 AND RAPID DIAGNOSTIC TESTS IN THE DIAGNOSIS OF INFECTION BY COVID-19. A PROSPECTIVE MULTI-CENTRIC STUDY.

2020 ◽  
Author(s):  
Rosalinda Pieruzzini ◽  
Carlos Ayala ◽  
Jose Navas ◽  
Wilneg Carolina Rodriguez ◽  
Nathalia Parra ◽  
...  
Keyword(s):  
Predictive Value ◽  
Diagnostic Tests ◽  
Rapid Diagnostic Tests ◽  
Variable Degree ◽  
Rt Pcr ◽  
Taste Test ◽  
Taste Disorders ◽  
Coronavirus Infection ◽  
Diagnosis Of Infection

There is a relationship between smell and taste disturbances and coronavirus infection. These symptoms have been considered the best predictor of coronavirus infection, for this reason, it was decided to evaluate the predictive value of the smell and taste test and its association with the results of SARS-CoV-2 PCR-RT and rapid diagnostic tests. in the diagnosis of pathology. Methodology: 248 patients divided into 3 groups: asymptomatic, symptomatic without chemosensory disorders, and chemosensory disorders alone. All of them underwent SARS-CoV-2 PCR-RT, a rapid diagnostic test and a test of Venezuelan smell and basic taste at the beginning. Weekly follow-up with smell and taste test and SARS-CoV-2 PCR-RT until recovery. Results: 20.56% of patients had smell and taste disorders to a variable degree and were positive by SARS-CoV-PCR-RT. 2.15.3% of patients with chemosensory disorders were negative for COVID-19. The positive predictive value of the smell and taste test was 57.3; Sensitivity 41.13% and specificity 69.35%. There were no statistically significant differences by age, sex and chemosensory disorders. The predominant chemosensory disorder was the combination of mild hyposmia and hypogeusia and appeared in the company of other symptoms. Recovery occurred in an average of 8.5 days, asynchronously with the SARS-CoV-2 RT-PCR negativization, which occurred up to more than 15 days after the senses recovered. Maximum time of negativization of the RT-PCR of 34 days. Conclusion: chemosensory disorders are a symptom and / or sign of coronavirus disease but cannot be considered as predictors of said disease in this population studied. The gold standard remains the SARS-CoV-2 PCR-RT test. Rapid diagnostic tests should be used for follow-up. Recommendations: it is necessary to expand the sample, include routine psychophysical smell and taste tests to screen cases and take race and virus mutations into consideration to explain behavior in certain populations. Key words: Smell, taste, coronavirus, test, diagnosis.

scholarly journals Self-Collected Samples to Detect SARS-CoV-2: Direct Comparison of Saliva, Tongue Swab, Nasal Swab, Chewed Cotton Pads and Gargle Lavage

2021 ◽  
Vol 10 (24) ◽  
pp. 5751
Author(s):  
Niko Kohmer ◽  
Lisa Eckermann ◽  
Boris Böddinghaus ◽  
Udo Götsch ◽  
Annemarie Berger ◽  
...  
Keyword(s):  
Nasal Swab ◽  
Clinical Symptoms ◽  
Tap Water ◽  
Diagnostic Sensitivity ◽  
Lower Sensitivity ◽  
Limited Data ◽  
Sample Collection ◽  
Rt Pcr ◽  
Nasal Swabs ◽  
Different Types

Testing for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) by RT-PCR is a vital public health tool in the pandemic. Self-collected samples are increasingly used as an alternative to nasopharyngeal swabs. Several studies suggested that they are sufficiently sensitive to be a useful alternative. However, there are limited data directly comparing several different types of self-collected materials to determine which material is preferable. A total of 102 predominantly symptomatic adults with a confirmed SARS-CoV-2 infection self-collected native saliva, a tongue swab, a mid-turbinate nasal swab, saliva obtained by chewing a cotton pad and gargle lavage, within 48 h of initial diagnosis. Sample collection was unsupervised. Both native saliva and gargling with tap water had high diagnostic sensitivity of 92.8% and 89.1%, respectively. Nasal swabs had a sensitivity of 85.1%, which was not significantly inferior to saliva (p = 0.092), but 16.6% of participants reported they had difficult in self-collection of this sample. A tongue swab and saliva obtained by chewing a cotton pad had a significantly lower sensitivity of 74.2% and 70.2%, respectively. Diagnostic sensitivity was not related to the presence of clinical symptoms or to age. When comparing self-collected specimens from different material, saliva, gargle lavage or mid-turbinate nasal swabs may be considered for most symptomatic patients. However, complementary experiments are required to verify that differences in performance observed among the five sampling modes were not attributed to collection impairment.

scholarly journals Sampling site for SARS-CoV-2 RT-PCR—An intrapatient four-site comparison from Tampere, Finland

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0260184
Author(s):  
Dominik Kerimov ◽  
Pekka Tamminen ◽  
Hanna Viskari ◽  
Lauri Lehtimäki ◽  
Janne Aittoniemi
Keyword(s):  
Informed Consent ◽  
Study Design ◽  
Nasal Swab ◽  
Sampling Site ◽  
Threshold Values ◽  
Rt Pcr ◽  
Cycle Threshold ◽  
Significant Difference ◽  
Nasal Swabs ◽  
Written Informed Consent

Background SARS-CoV-2 diagnosis relies on the performance of nasopharyngeal swabs. Alternative sample sites have been assessed but the heterogeneity of the studies have made comparing different sites difficult. Objectives Our aim was to compare the performance of four different sampling sites for SARS-CoV-2 samples with nasopharynx being the benchmark. Study design COVID-19 positive patients were recruited prospectively, and samples were collected and analysed for SARS-CoV-2 with RT-PCR from all four anatomical sites in 43 patients, who provided written informed consent. Results All anterior nasal and saliva samples were positive, while two oropharyngeal samples were negative. There was no significant difference in the cycle threshold values of nasopharyngeal and anterior nasal samples while saliva and oropharynx had higher cycle threshold values. Conclusions Anterior nasal swab performs as good as nasopharynx swab with saliva also finding all the positives but with higher cycle threshold values. Thus, we can conclude that anterior nasal swabs can be used for SARS-CoV-2 detection instead of nasopharyngeal swabs if the situation would require so.

scholarly journals Sensitive detection and quantification of SARS-CoV-2 in saliva

2020 ◽  
Author(s):  
Mustafa Fatih Abasiyanik ◽  
Blake Flood ◽  
Jing Lin ◽  
Sefika Ozcan ◽  
Sherin J Rouhani ◽  
...  
Keyword(s):  
Nasal Swab ◽  
Digital Pcr ◽  
Rt Pcr ◽  
Community Screening ◽  
Viral Loads ◽  
Reverse Transcription Pcr ◽  
Testing Facility ◽  
Wide Range ◽  
Nasal Swabs ◽  
Higher Sensitivity

AbstractSaliva has significant advantages as a test medium for detection of SARS-CoV-2 infection in patients, such as ease of collection, minimal requirement of supplies and trained personnel, and safety. Comprehensive validation in a large cohort of prospectively collected specimens with unknown SARS-CoV-2 status should be performed to evaluate the potential and limitations of saliva-based testing. We developed a saliva-based testing pipeline for detection of SARS-CoV-2 nucleic acids using real-time reverse transcription PCR (RT-PCR) and droplet digital PCR (ddPCR) readouts, and measured samples from 137 outpatients tested at a curbside testing facility and 29 inpatients hospitalized for COVID-19. These measurements were compared to the nasal swab results for each patient performed by a certified microbiology laboratory. We found that our saliva testing positively detects 100% (RT-PCR) and 93.75% (ddPCR) of curbside patients that were identified as SARS-CoV-2 positive by the Emergency Use Authorization (EUA) certified nasal swab testing assay. Quantification of viral loads by ddPCR revealed an extremely wide range, with 1 million-fold difference between individual patients. Our results demonstrate for both community screening and hospital settings that saliva testing reliability is on par with that of the nasal swabs in detecting infected cases, and has potential for higher sensitivity when combined with ddPCR in detecting low-abundance viral loads that evade traditional testing methods.

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