scholarly journals Clinical evaluation of the Roche/SD Biosensor rapid antigen test with symptomatic, non-hospitalized patients in a municipal health service drive-through testing site

2020 ◽  
Author(s):  
Zsὁfia Iglὁi ◽  
Jans Velzing ◽  
Janko van Beek ◽  
David van de Vijver ◽  
Georgina Aron ◽  
...  
Keyword(s):  
Viral Load ◽  
Rapid Test ◽  
Contact Tracing ◽  
Gene Copy ◽  
Nasopharyngeal Swab ◽  
List Type ◽  
Antigen Test ◽  
Rt Pcr ◽  
Outbreak Management ◽  
Testing Site

AbstractBackgroundRapid detection of infectious individuals is essential in stopping the further spread of SARS-CoV-2. Although rapid antigen test is not as sensitive as the gold standard RT-PCR, the time to result is decreased by day(s), strengthening the effectiveness of contact tracing.MethodsThe Roche/SD Biosensor lateral flow antigen rapid test was evaluated in a mild symptomatic population at a large drive through testing site. A second nasopharyngeal swab was directly tested with the rapid test on site and results were compared to RT-PCR and virus culture. Date of onset and symptoms were analysed using data from a clinical questionnaire.ResultsWe included 970 persons with complete data. Overall sensitivity and specificity were 84.9% (CI95% 79.1-89.4) and 99.5% (CI95% 98.7-99.8) which translated into a positive predictive value of 97.5% (CI95% 94.0-99.5) under the current regional PCR positivity of 19.2%. Sensitivity for people with high loads of viral RNA (ct <30, 2.17E+05 E gene copy/ml) and who presented within 7 days since symptom onset increased to 95.8% (CI95% 90.5-98.2). Band intensity and time to result correlated strongly with viral load thus strong positive bands could be read before the recommended time. Around 98% of all viable specimen with ct <30 were detected successfully indicating that the large majority of infectious people can be captured with this test.ConclusionAntigen rapid tests can detect mildly symptomatic cases in the early phase of disease thereby identifying the most infectious individuals. Using this assay can have a significant value in the speed and effectiveness of SARS-CoV-2 outbreak management.SummaryPeople with early onset and high viral load were detected with 98.2% sensitivity.97% of individuals in which virus could be cultured were detected by the rapid test.This test is suitable to detect mild symptomatic cases.

scholarly journals Multicenter evaluation of the Panbio™ COVID-19 Rapid Antigen-Detection Test for the diagnosis of SARS-CoV-2 infection

2020 ◽  
Author(s):  
Paloma Merino-Amador ◽  
Jesús Guinea ◽  
Irene Muñoz-Gallego ◽  
Patricia González-Donapetry ◽  
Juan-Carlos Galán ◽  
...  
Keyword(s):  
Viral Load ◽  
Clinical Symptoms ◽  
False Negative ◽  
Rapid Test ◽  
Antigen Detection ◽  
Nasopharyngeal Swab ◽  
Diagnostic Strategy ◽  
Rt Pcr ◽  
University Hospitals ◽  
Kappa Score

AbstractThe standard RT-PCR assay for COVID-19 is laborious and time-consuming, limiting the availability of testing. Rapid antigen-detection tests are faster and less expensive; however, the reliability of these tests must be validated before they can be used widely. The objective of this study was to determine the reliability of the PanbioTM COVID-19 Ag Rapid Test Device (PanbioRT) (Abbott) for SARS-CoV-2 in nasopharyngeal swab specimens. This was a prospective multicenter study in ten Spanish university hospitals of patients from hospital units with clinical symptoms or epidemiological criteria for COVID-19. Patients whose onset of symptoms or exposure was more than 7 days earlier were excluded. Two nasopharyngeal exudate samples were taken to perform the PanbioRT and a diagnostic RT-PCR test. Among the 958 patients studied, 359 (37.5%) were positive by RT-PCR and 325 (33.9%) were also positive by the PanbioRT. Agreement was 95.7% (kappa score: 0.90). All 34 false-negative PanbioRT results were in symptomatic patients, with 23.5% of them at 6–7 days since the onset of symptoms and 58.8% presenting CT >30 values for RT-PCR, indicating a low viral load. Overall sensitivity and specificity for the PanbioRT were 90.5% and 98.8%, respectively. The PanbioRT provides good clinical performance as a point-of-care test, with even more reliable results for patients with a shorter clinical course of the disease or a higher viral load. While this study has had a direct impact on the national diagnostic strategy for COVID-19 in Spain, the results must be interpreted based on the local epidemiological context.

scholarly journals Performance characteristics of a rapid SARS-CoV-2 antigen detection assay at a public plaza testing site in San Francisco

2020 ◽  
Author(s):  
Genay Pilarowski ◽  
Paul Lebel ◽  
Sara Sunshine ◽  
Jamin Liu ◽  
Emily Crawford ◽  
...  
Keyword(s):  
Viral Load ◽  
San Francisco ◽  
High Viral Load ◽  
Performance Characteristics ◽  
Viral Rna ◽  
Antigen Test ◽  
Rt Pcr ◽  
Detection Assay ◽  
Community Transmission ◽  
Testing Site

ABSTRACTWe evaluated the performance of the Abbott BinaxNOW™ Covid-19 rapid antigen test to detect virus among persons, regardless of symptoms, at a public plaza site of ongoing community transmission. Titration with cultured clinical SARS-CoV-2 yielded a human observable threshold between 1.6×104-4.3×104 viral RNA copies (cycle threshold (Ct) of 30.3-28.8 in this assay). Among 878 subjects tested, 3% (26/878) were positive by RT-PCR, of which 15/26 had a Ct<30, indicating high viral load. 40% (6/15) of Ct<30 were asymptomatic. Using this Ct<30 threshold for Binax-CoV2 evaluation, the sensitivity of the Binax-CoV2 was 93.3% (14/15), 95% CI: 68.1-99.8%, and the specificity was 99.9% (855/856), 95% CI: 99.4-99.9%.

scholarly journals Performance characteristics of a rapid SARS-CoV-2 antigen detection assay at a public plaza testing site in San Francisco

2021 ◽  
Author(s):  
Genay Pilarowski ◽  
Paul Lebel ◽  
Sara Sunshine ◽  
Jamin Liu ◽  
Emily Crawford ◽  
...  
Keyword(s):  
Viral Load ◽  
San Francisco ◽  
High Viral Load ◽  
Performance Characteristics ◽  
Viral Rna ◽  
Antigen Test ◽  
Rt Pcr ◽  
Detection Assay ◽  
Community Transmission ◽  
Testing Site

Abstract We evaluated the performance of the Abbott BinaxNOW TM Covid-19 rapid antigen test (Binax-CoV2) to detect virus among persons, regardless of symptoms, at a public plaza site of ongoing community transmission. Titration with cultured SARS-CoV-2 yielded a human observable threshold between 1.6x10 4-4.3x10 4 viral RNA copies (cycle threshold (Ct) of 30.3-28.8). Among 878 subjects tested, 3% (26/878) were positive by RT-PCR, of which 15/26 had Ct&lt;30, indicating high viral load. 40% (6/15) of Ct&lt;30 were asymptomatic. Using this Ct&lt;30 threshold for Binax-CoV2 evaluation, the sensitivity of Binax-CoV2 was 93.3% (14/15), 95% CI: 68.1-99.8%, and the specificity was 99.9% (855/856), 95% CI: 99.4-99.9%.

scholarly journals Clinical evaluation of the SD Biosensor SARS-CoV-2 saliva antigen rapid test with symptomatic and asymptomatic, non-hospitalized patients

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0260894
Author(s):  
Zsofia Igloi ◽  
Jans Velzing ◽  
Robin Huisman ◽  
Corine Geurtsvankessel ◽  
Anoushka Comvalius ◽  
...  
Keyword(s):  
Saliva Sample ◽  
Rapid Test ◽  
Hospitalized Patients ◽  
Nasopharyngeal Swab ◽  
Lower Sensitivity ◽  
Rt Pcr ◽  
Virus Culture ◽  
Testing Site ◽  
Asymptomatic Individuals ◽  
Post Onset

Background Performance of the SD Biosensor saliva antigen rapid test was evaluated at a large designated testing site in non-hospitalized patients, with or without symptoms. Method All eligible people over 18 years of age presenting for a booked appointment at the designated SARS-CoV-2 testing site were approached for inclusion and enrolled following verbal informed consent. One nasopharyngeal swab was taken to carry out the default antigen rapid test from which the results were reported back to the patient and one saliva sample was self-taken according to verbal instruction on site. This was used for the saliva antigen rapid test, the RT-PCR and for virus culture. Sensitivity of the saliva antigen rapid test was analyzed in two ways: i, compared to saliva RT-PCR; and ii, compared to virus culture of the saliva samples. Study participants were also asked to fill in a short questionnaire stating age, sex, date of symptom onset. Recommended time of ≥30mins since last meal, drink or cigarette if applicable was also recorded. The study was carried out in February-March 2021 for 4 weeks. Results We could include 789 people with complete records and results. Compared to saliva RT-PCR, overall sensitivity and specificity of the saliva antigen rapid test was 66.1% and 99.6% which increased to 88.6% with Ct ≤30 cutoff. Analysis by days post onset did not result in higher sensitivities because the large majority of people were in the very early phase of disease ie <3 days post onset. When breaking down the data for symptomatic and asymptomatic individuals, sensitivity ranged from 69.2% to 50% respectively, however the total number of RT-PCR positive asymptomatic participants was very low (n = 5). Importantly, almost all culture positive samples were detected by the rapid test. Conclusion Overall, the potential benefits of saliva antigen rapid test, could outweigh the lower sensitivity compared to nasopharyngeal antigen rapid test in a comprehensive testing strategy, especially for home/self-testing and in vulnerable populations like elderly, disabled or children where in intrusive testing is either not possible or causes unnecessary stress.

scholarly journals Performance of Self-Collected Saliva Testing Compared with Nasopharyngeal Swab Testing for the Detection of SARS-CoV-2

Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 895
Author(s):  
Florence Carrouel ◽  
Martine Valette ◽  
Hervé Perrier ◽  
Maude Bouscambert-Duchamp ◽  
Claude Dussart ◽  
...  
Keyword(s):  
Viral Load ◽  
Quantitative Pcr ◽  
Statistical Analyses ◽  
Fair Agreement ◽  
Quantitative Detection ◽  
Nasopharyngeal Swab ◽  
Rt Pcr ◽  
Noninvasive Techniques ◽  
Concordance Probability ◽  
Salivary Test

The aim of this study was to determine whether self-collected pure saliva (SCPS) is comparable to nasopharyngeal (NP) swabs in the quantitative detection of SARS-CoV-2 by RT-PCR in asymptomatic, mild patients with confirmed COVID-19. Thirty-one patients aged from 18 to 85 years were included between 9 June and 11 December 2020. A SCPS sample and a NP sample were taken for each patient. Quantitative PCR was performed to detect SARS-CoV-2 viral load. Results of SCPS vs NP samples testing were compared. Statistical analyses were performed. Viral load was significantly correlated (r = 0.72). The concordance probability was estimated at 73.3%. In symptomatic adults, SCPS performance was similar to that of NP swabs (Percent Agreement = 74.1%; p = 0.11). Thus, the salivary test based on pure oral saliva samples easily obtained by noninvasive techniques has a fair agreement with the nasopharyngeal one in asymptomatic, mild patients with a confirmed diagnosis of COVID-19.

scholarly journals SARS-CoV-2 in peritoneal swabs from asymptomatic patients undergoing emergency abdominal surgery

2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
Jasim AlAradi ◽  
Rawan A Rahman AlHarmi ◽  
Mariam AlKooheji ◽  
Sayed Ali Almahari ◽  
Mohamed Abdulla Isa ◽  
...  
Keyword(s):  
Peritoneal Fluid ◽  
Case Series ◽  
Rapid Test ◽  
Nasopharyngeal Swab ◽  
Rt Pcr ◽  
Protective Measures ◽  
The Public ◽  
Asymptomatic Patients ◽  
Number Of Patients ◽  
Viral Transfer

Abstract This is a case series of five patients with acute abdomen requiring surgery who tested positive for coronavirus disease 2019 (COVID-19) and were asymptomatic, with the purpose of detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in peritoneal fluid. Nasopharyngeal swab was done as a prerequisite for admission or prior to admission as part of random testing. Two methods of viral testing were employed: Xpert® Xpress SARS-CoV-2 (rapid test) and real-time reverse transcription polymerase chain reaction (RT-PCR). Either or both tests were done, with the former performed for patients requiring surgery immediately. Surgery was performed within 24–36 h from admission. Peritoneal fluid swabs were obtained for the detection of SARS-CoV-2 using RT-PCR test. Swabs were immediately placed in viral transfer media and delivered to the public health laboratory in an ice bag. SARS-CoV-2 was not detected in peritoneal swabs. Due to the limited number of patients, further studies are required; yet, protective measures should still be taken by surgeons when dealing with COVID-19 cases.

scholarly journals Avian influenza and Newcastle disease virusindead chickens in markets in Dhaka, Bangladesh in 2011-2012

2017 ◽  
Vol 33 (1) ◽  
pp. 8-15
Author(s):  
LR Barman ◽  
RD Sarker ◽  
BC Das ◽  
EH Chowdhury ◽  
PM Das ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Avian Influenza ◽  
Newcastle Disease ◽  
Rapid Test ◽  
Type A ◽  
Antigen Test ◽  
Rt Pcr ◽  
Test Kit ◽  
Live Bird

A virological survey for avian influenza (AI) and Newcastle disease (ND) was conducted in two selected live bird markets (LBMs), namely Kaptan Bazar and Karwan Bazar in Dhaka city, Bangladesh from August 2011 to July 2012. A total of 513 dead chickens were collected. An immune-chromatographic rapid antigen test for Type A influenza virus and both conventional and real time RT-PCR were used for the detection and characterization of AI and ND viruses. All carcasses were first screened by the rapid antigen test kit and 93 were positive for Type A influenza virus. RT-PCR on a representative number of rapid antigen test positive samples (n = 24) confirmed the presence of Type A influenza virus and mostly H5 influenza virus (22 out of 24 tested samples). Influenza rapid test negative samples (n = 420) were subjected to routine necropsy. Heat stress, suffocation and physical injury were the most common cause of mortality (163 cases), followed by ND, suspected to be the cause of 85 deaths. On molecular investigation of these 85 samples, the presence of ND virus was confirmed in 59 and AI virus in 6; 15 were negative for both ND and AI viruses and 5 were unsuitable for investigation. Among the 59 ND confirmed cases 18 also contained AI virus. In summary, out of 513 carcasses 117 (22.81%) contained AI virus and 59 (11.50%) contained ND virus. Eighteen (3.51%) carcasses contained both AI and ND viruses. The findings suggest that both AI and ND should be considered as major threats to the poultry industry.Bangl. vet. 2016. Vol. 33, No. 1, 8-15

scholarly journals Field evaluation of a rapid antigen test (Panbio™ COVID-19 Ag Rapid Test Device) for the diagnosis of COVID-19 in primary healthcare centers

2020 ◽  
Author(s):  
Eliseo Albert ◽  
Ignacio Torres ◽  
Felipe Bueno ◽  
Dixie Huntley ◽  
Estefanía Molla ◽  
...  
Keyword(s):  
Primary Healthcare ◽  
Rapid Test ◽  
Field Evaluation ◽  
Antigen Test ◽  
Rt Pcr ◽  
Test Device ◽  
Specificity And Sensitivity ◽  
Primary Healthcare Centers

AbstractWe evaluated the Panbio™ COVID-19 AG Rapid Test Device (RAD) for the diagnosis of COVID-19 in symptomatic patients attended in primary healthcare centers (n=412). Overall specificity and sensitivity of RAD was 100% and 79.6%, respectively, taking RT-PCR as the reference. SARS-CoV-2 could not be cultured from specimens yielding RT-PCR+/RAD- results.

scholarly journals Epidemiology of COVID-19 and effect of public health interventions, Chennai, India, March - October 2020

2021 ◽  
Author(s):  
M Jagadeesan ◽  
Parasuraman Ganeshkumar ◽  
Prabhdeep Kaur ◽  
Hemalatha Masanam Sriramulu ◽  
Manikandanesan Sakthivel ◽  
...  
Keyword(s):  
Public Health ◽  
Case Fatality ◽  
Contact Tracing ◽  
Severe Illness ◽  
List Type ◽  
Rt Pcr ◽  
Case Fatality Ratio ◽  
Metropolitan City ◽  
Lessons Learnt ◽  
Public Health Strategies

AbstractObjectivesTo describe the public health strategies and their effect in controlling the COVID-19 pandemic from March to October 2020 in Chennai, India.SettingChennai, a densely populated metropolitan city in Southern India, was one of the five cities which contributed to more than half of the COVID-19 cases in India.ParticipantsWe collected the de-identified line list of all the 192,450 COVID-19 case-patients reported from 17 March to 31 October 2020 in Chennai and their contacts for the analysis. We defined a COVID-19 case-patient based on the RT-PCR positive test in one of the Government approved labs.Outcome measuresThe primary outcomes of interest were incidence of COVID-19 per million population, case fatality ratio, deaths per million and the effective reproduction number (Rt). We also analysed the indicators for surveillance, testing, contact tracing and isolation.ResultsOf the 192,450 RT-PCR confirmed COVID-19 case-patients reported in Chennai from 17 March-31 October 2020, 114,889 (60%) were males. The highest incidence was 41,064 per million population among the 61-80 years. The incidence peaked during June 2020 at 5239 per million and declined to 3,627 per million in October 2020. The city reported 3,543 deaths, with a case fatality ratio (CFR) of 1.8% and the crude death rate was 431 per million. When lockdown began, Rt was high (4.2) in March and fluctuated from April to June 2020. The Rt dropped below one by the first week of July and remained so until October 2020, even with the relaxation of restrictionsConclusionThe combination of public health strategies controlled the COVID-19 epidemic in a large, densely populated city in India. We recommend continuing the interventions to prevent resurgence, even as vaccination is being rolled out.StrengthsWe did a comprehensive analysis of COVID-19 strategies and outcome in a large, densely populated metropolitan city in India.We documented that the community-centric public health strategies were feasible and effective in controlling the COVID-19 outbreak even in a large, thickly populated cityThe lessons learnt are relevant to similar settings in low-and middle-income countries. Given the ongoing multiple waves of COVID-19 and the difficulty in controlling the transmission, our experience and lessons learnt will be valuable for policymakers and scientific advisors globallyLimitationsWe analysed the data available from the GCC database and not from the hospitals where patients with moderate to severe illness were admitted. Hence, we could not report the severity of illness among admitted patients.Second, the COVID-19 incidence might have been underestimated while testing was low during the early phase of the epidemic

scholarly journals Performance of SARS-CoV-2 rapid antigen test compared with real-time RT-PCR in asymptomatic individuals

2021 ◽  
Author(s):  
Mónica Peña ◽  
Manuel Ampuero ◽  
Carlos Garcés ◽  
Aldo Gaggero ◽  
Patricia García ◽  
...  
Keyword(s):  
Real Time ◽  
False Negative ◽  
Pivotal Role ◽  
Contact Tracing ◽  
Antigen Test ◽  
Rt Pcr ◽  
Asymptomatic Carriers ◽  
Asymptomatic Individuals ◽  
Pcr Diagnostics

AbstractScreening, testing and contact tracing plays a pivotal role in the control of COVID-19 pandemic. To carry out this strategy it is necessary to increase the testing capacity. Here, we compared a SARS CoV-2 rapid antigen test (RAT) and RT-PCR in 842 asymptomatic individuals from Tarapacá, Chile. We report a sensibility of 69.86%, a specificity of 99.61%, PPV of 94.44% and NPP of 97.22% with Ct values (Ct > 27) that were significantly higher among individuals with false-negative RAT. These results support the fact that RAT might have a significant impact in the identification of asymptomatic carriers in areas that lack well-equipped laboratories to perform SARS-CoV-2 real -time RT-PCR diagnostics or the results take more than 24-48 hours, as well as zones with high traffic of individuals, such as border/customs, airports, interregional bus, train stations or in any mass testing campaign requiring rapid results.

Sign in / Sign up

Export Citation Format

Share Document