Surveillance of noninvasive group A Streptococcus infections in French ambulatory pediatrics before and during the COVID-19 pandemic: a prospective multicenter study from 2018-2022.

OBJECTIVES: We evaluated the burden of noninvasive group A Streptococcus (GAS) infections in ambulatory pediatrics before and during the COVID-19 pandemic in France. METHODS: We analyzed data from a national network of ambulatory pediatricians between 2018 and 2022. Clinicians evaluating children ≤15 years old for tonsillopharyngitis, perianal infections, paronychia/blistering dactylitis, and scarlet fever were invited to perform a rapid antigen detection test (RADT) for GAS. Monthly incidence of noninvasive GAS infections per 10,000 visits was modeled using time series analysis, considering two breakpoints: March 2020 (first national lockdown) and March 2022 (end of mandatory mask-wearing in schools). RESULTS: Over the study period, 125 pediatricians recorded 271,084 infectious episodes. GAS-related illnesses represented 4.3% of all infections. In March 2020, the incidence of GAS diseases decreased by 84.5% (P <0.001), with no significant trend until March 2022. After March 2022, the incidence significantly increased (+23.8% per month, P <0.001), with similar patterns across all monitored GAS-related diseases. CONCLUSION: By using routine clinical data and RADTs, we have monitored changes in the incidence of noninvasive GAS infections in ambulatory pediatrics. COVID-19 mitigation measures have had a major impact on the epidemiology of noninvasive GAS infections, but their relaxation was followed by a surge above baseline levels.

Verification of the Performance of the Panbio COVID-19 Ag Rapid Test Device for Implementation in the Clinical Laboratory

Objectives: The Panbio COVID-19 Ag Rapid Test Device (Panbio COVID-19 Ag, Abbott Rapid Diagnostics) is a lateral flow immunochromatographic assay targeting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleoprotein in nasopharyngeal specimens for the diagnosis of coronavirus disease 2019 (COVID-19). This study aimed to verify the performance of the Panbio COVID-19 Ag for implementation in clinical laboratories. Method(s): Sixty nasopharyngeal swab specimens (30 positive and 30 negative) dipped in transport medium, and COVID-19 was confirmed using real-time RT-PCR using Allplex SARS-CoV-2 assay (Seegene), were tested using the Panbio COVID-19 Ag. Reproducibility was evaluated using positive and negative control materials. Sensitivity and specificity were calculated based on the results of realtime RT-PCR as the standard test method. Result(s): Reproducibility was confirmed by the consistent results of repeated tests of the quality control materials. The overall sensitivity and specificity of Panbio COVID-19 Ag were 50.0% and 100.0%, respectively. Panbio COVID-19 Ag demonstrated high sensitivity (88.2%) in analyzing the detection limit cycle threshold (Ct) value of 26.67 provided by the manufacturer as a positive criterion, and the sensitivity was 100.0% for the positive criterion of Ct values <25, although it was less sensitive for Ct > 25. Conclusion(s): Considering the high sensitivity for positive samples with Ct values <25 and the rapid turnaround of results, Panbio COVID-19 Ag can be used in clinical laboratories to diagnose COVID-19 in limited settings. Copyright © 2023 Ewha Womans University College of Medicine and Ewha Medical Research Institute.

Clinical effectiveness of molnupiravir in patients with COVID-19 undergoing haemodialysis.

BACKGROUND: Molnupiravir is an essential oral antiviral agent against coronavirus disease 2019 (COVID-19); however, its real-world effectiveness has not been evaluated in patients undergoing haemodialysis (HD). METHODS: This multi-centre retrospective study, involving 225 patients undergoing HD with initially mild or asymptomatic COVID-19, was conducted to compare the risks of 30-day COVID-19-related acute care visits between patients receiving and not receiving molnupiravir. Patients who received molnupiravir were stratified by rapid antigen detection (RAD) test results on day 7 after disease onset to assess whether rapid molnupiravir introduction accelerated viral clearance. RESULTS: Thirty-day COVID-19-related acute care visits were reported in 9.41% and 21.74% of the molnupiravir and control groups, respectively, and use of molnupiravir markedly reduced the risk of acute care visits after adjusting for baseline characteristics via propensity score weighting [hazard ratio 0.218, 95% confidence interval (CI) 0.074-0.642; P=0.006]. The tolerability of molnupiravir in the enrolled patients was generally acceptable, with only 11.88% of molnupiravir users reporting mild adverse events. Moreover, rapid initiation of molnupiravir within 1 day of COVID-19 onset was an independent predictor of conversion to a negative RAD test result on day 7 after disease onset (odds ratio 6.207, 95% CI 2.509-15.358; P<0.001). CONCLUSIONS: Molnupiravir is well tolerated and decreases the medical needs in patients with COVID-19 undergoing HD. Furthermore, the rapid initiation of molnupiravir accelerates viral clearance in patients with COVID-19 undergoing HD. These findings highlight the therapeutic role of molnupiravir for this vulnerable population.

Performance of 20 rapid antigen detection tests to detect SARS-CoV-2 B.1.617.2 (Delta) and B.1.1.529 (Omicron) variants using a clinical specimen panel from January 2022, Berlin, Germany.

BackgroundThere are conflicting reports on the performance of rapid antigen detection tests (RDT) in the detection of the SARS-CoV-2 Omicron (B.1.1.529) variant; however, these tests continue to be used frequently to detect potentially contagious individuals with high viral loads.AimThe aim of this study was to investigate comparative detection of the Delta (B.1.617.2) and Omicron variants by using a selection of 20 RDT and a limited panel of pooled combined oro- and nasopharyngeal clinical Delta and Omicron specimens.MethodsWe tested 20 CE-marked RDT for their performance to detect SARS-CoV-2 Delta and Omicron by using a panel of pooled clinical specimens collected in January 2022 in Berlin, Germany.ResultsWe observed equivalent detection performance for Delta and Omicron for most RDT, and sensitivity was widely in line with our previous pre-Delta/Omicron evaluation. Some variation for individual RDT was observed either for Delta vs Omicron detection, or when compared with the previous evaluation, which may be explained both by different panel sizes resulting in different data robustness and potential limitation of batch-to-batch consistency. Additional experiments with three RDT using non-pooled routine clinical samples confirmed comparable performance to detect Delta vs Omicron. Overall, RDT that were previously positively evaluated retained good performance also for Delta and Omicron variants.ConclusionOur findings suggest that currently available RDT are sufficient for the detection of SARS-CoV-2 Delta and Omicron variants.

Evaluation of diagnostic performance of SARS-CoV-2 detection kits: a comparative study.

Background: Coronavirus Disease 2019 (COVID-19) pandemic has hit many countries worldwide. Rapid and accurate diagnosis is crucial to reduce disease burden. Many commercial kits have become available, but their performance needs to be assessed. This study aimed at evaluation of the diagnostic performance of real-time polymerase chain reaction (RT-PCR) and Rapid Antigen detection (RAD) kits for detecting Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Five hundred sixty-four Nasopharyngeal swab specimens sent to Molecular Laboratory at Ain Shams University Specialized Hospital for SARS-CoV-2 PCR testing collected from 564 subjects who attended the outpatient clinic for sample collection were randomly selected. All samples were tested for SARS-CoV-2 PCR using Viasure. Each time a recent kit was introduced, 94 samples, previously tested using Viasure, were used to determine the performance characteristics of the recent kit in comparison with Viasure, including Fast Track Diagnostics (FTD), DNA Technology, QiaPrep, Xpress SARS-CoV-2, ID NOW COVID-19 assay and Artron COVID-19 Antigen test kit. Results: Upon comparison, FTD, DNA Technology, QiaPrep, Xpress SARS-CoV-2 and ID Now showed positive percent agreement, 100%, 100%, 97.7%, 100%, 100% negative percent agreement, 86%, 100%, 98.8%, 90%, 100%, respectively. The RAD kit results, when compared with RT-PCR, showed high sensitivity at cycle threshold (Ct) < 30, low sensitivity at Ct ≥ 30, while specificity was 100%. Conclusion: Fast track, DNA Technology, QiaPrep, Xpress SARS-CoV-2 and ID Now showed good diagnostic performance. Positive RAD rule in SARS-CoV-2 infection, however negative results should be correlated with clinical condition and molecular testing.

Efficacy Of PanbioTM Covid-19 Ag Rapid Test In Sars-Cov-2 Detection: Comparison With RT-PCR Test.

Background: Evidence on performance of Rapid Antigen Detection Tests to recognize SARS-CoV-2 symptomatic patients in our context is limited. This study was aimed to evaluate Panbio™ COVID-19 Ag Rapid Test Device (Abbott Diagnostics, Jena, Germany) in identifying SARS-CoV-2 infection in comparison with RT-PCR test. Methods: This cross-sectional validation study was carried out at Margalla Hospital, Taxila from October, 2020 to March, 2021. Three hundred and eighty-two participants of both gender and all ages, symptomatic for 3-4 days were included in this study. For each participant, two nasopharyngeal swabs were collected by trained lab technicians according to SOPs, one for Rapid Antigen Test and other for RT-PCR.Covid-19 antibodies were checked 4-6 weeks after symptoms among 77 randomly selected participants to further evaluate the performance of Rapid Antigen Test. Data was analyzed using SPSS-26. Results: The mean age of the participants was 43.1 years (SD=15.9). More than half of participants were males (n=213%=55.8) and 169 (44.2%) were females. Sensitivity of Rapid Antigen Test was calculated to be 94.3%, whereas the specificity was 39.7%. Out of 34 RT-PCR negatives that were initially detected positive on Rapid Antigen Test, 33 demonstrated presence of COVID-19 antibodies. Conclusion: Panbio™ COVID-19 Ag Rapid Test was found to have 93.4% overall sensitivity and relatively low overall specificity (37.9%). Rapid antigen testing using Panbio™ COVID-19 Ag Rapid Test Device can be effectively used to scale up mass testing to interrupt transmissibility of COVID-19 infection by generating quick result.

The evaluation results of proposed antigen rapid diagnostic tests for COVID-19: some possible factors might influence.

PURPOSE: In addition to existing gold standard qRT-PCR methods, there is a need to develop reliable rapid tests for infection control with early notification of COVID-19 cases to enable effective outbreak management. We evaluated the validity of the three Ag-RDT kits proposed by some companies in different countries by using qRT-PCR and analyzed its results. METHODS: Each of the three Ag-RDT kits (namely A, B, and C) was tested with 90 samples, consisting of samples with Ct ≤ 25, samples with Ct > 25, and negative SARS-CoV-2 PCR samples. RESULTS: This study showed that for samples with Ct > 25, all the three kits could not detect SARS-CoV-2 Ag (0% sensitivity) but showed 100% specificity. Meanwhile, for samples with Ct ≤ 25, kit C was the best (76.7% sensitivity and 100% specificity). The PPV of the three kits was 100%, but their NPV ranged 63-84.8%. Kit C showed the best accuracy (89.9%). Some factors might influence the results of evaluation, such as variation of virus proteins and transportation-storage of the kits. CONCLUSION: The overall specificity of the three kits for all samples was high; however, all of them have not met the minimum performance requirements of ≥ 80% sensitivity for samples with Ct ≤ 25. The validation test is much necessary to be carried out by the authority in national health care to ensure the feasibility of the kit for point-of-care testing (POCT) of COVID-19. Some factors that might influence should be anticipated to increase their sensitivities and specificities.

Evaluation of the Rapid Antigen Detection Test for Diagnosing SARS-CoV-2 during the COVID-19 Pandemic: Experience from a Centralized Isolation Site in Shanghai, China.

Rapid and reliable diagnosis is important for the management of individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The rapid antigen detection test (RADT) is a rapid, inexpensive, and easy method. Several studies have reported that RADTs performed well in many countries; however, very few studies have been reported in China. In this study, we assessed the performance of the RADT (Ediagnosis COVID-19 antigen test kit). This study was conducted in a centralized isolation site in Shanghai and enrolled 716 patients with COVID-19 and 203 noninfected participants. Nasopharyngeal swabs from all participants were collected on the same day and tested using the RADT and real-time reverse transcription-PCR (RT-PCR). The performance of the RADT was evaluated in different scenarios, such as threshold cycle (CT) values, symptomatic phase, and symptoms on the day of testing. The results demonstrated that the sensitivity for patients with CT values lower than 20 was 96.55% (95% confidence interval [CI], 87.05 to 99.4). The sensitivities were 78.4% (95% CI, 69.96 to 85.05) for participants within 5 days after the first RT-PCR-positive result and 90.77% (95% CI, 80.34 to 96.19) within 5 days after symptom onset. Moreover, the sensitivity of the RADT was more than 80% for patients with symptoms on the day of testing, including fever (89.29%), cough (86.84%), stuffy nose (92.59%), runny nose (92%), sore throat (81.25%), and muscle pain (80.77%), especially for those with upper respiratory tract symptoms. The specificity of the RADT was good in all scenarios. During the SARS-CoV-2 epidemic, Ediagnosis performed excellently in individuals with a higher viral load (evidenced by lower CT values), individuals in the early symptomatic phase, and especially those with upper respiratory tract symptoms. IMPORTANCE RADTs have demonstrated excellent performance in many counties for screening SARS-CoV-2 infection, but very few studies have been conducted in China. The performance of RADTs is largely related to different real-life scenarios. In our study, the performance of the RADT was evaluated in different scenarios, such as CT values, symptomatic phase, and symptoms on the day of testing. The results demonstrated that Ediagnosis (an RADT made in China) performed excellently for individuals with a higher viral load (evidenced by lower CT values), individuals in the early symptomatic phase, and especially those with upper respiratory tract symptoms.

Evaluation of a Rapid Immunochromatographic Middle East Respiratory Syndrome Coronavirus Antigen Detection Assay

Middle East respiratory syndrome coronavirus (MERS-CoV) infection in humans has a high mortality of >30%. Dromedaries are the reservoir of MERS-CoV and the main source of human infections. However, MERS-CoV infections in dromedaries are usually subclinical. Rapid diagnosis of MERS-CoV infection in these animals is important in preventing camel-to-human transmission of the virus. The possible cross-reactivity of a previously reported rapid nucleocapsid protein-based antigen detection assay for MERS-CoV was examined with different CoVs, including Tylonycteris bat CoV HKU4, dromedary camel CoV UAE-HKU23, human CoV-229E, human CoV-OC43, severe acute respiratory syndrome CoV-2 and rabbit CoV HKU14, where none of them showed false-positive results. The assay was further validated using quantitative real-time reverse transcription-polymerase chain reaction-confirmed MERS-CoV-positive and MERS-CoV-negative dromedary nasal samples collected in Dubai, the United Arab Emirates, which showed that the rapid antigen detection assay has a specificity of 100% and sensitivity of 91.7%.

Head-to-head comparison of the accuracy of saliva and nasal rapid antigen SARS-CoV-2 self-testing: cross-sectional study.

BACKGROUND: The diagnostic accuracy of unsupervised self-testing with rapid antigen diagnostic tests (Ag-RDTs) is mostly unknown. We studied the diagnostic accuracy of a self-performed SARS-CoV-2 saliva and nasal Ag-RDT in the general population. METHODS: This large cross-sectional study consecutively included unselected individuals aged ≥ 16 years presenting for SARS-CoV-2 testing at three public health service test sites. Participants underwent molecular test sampling and received two self-tests (the Hangzhou AllTest Biotech saliva self-test and the SD Biosensor nasal self-test by Roche Diagnostics) to perform themselves at home. Diagnostic accuracy of both self-tests was assessed with molecular testing as reference. RESULTS: Out of 2819 participants, 6.5% had a positive molecular test. Overall sensitivities were 46.7% (39.3-54.2%) for the saliva Ag-RDT and 68.9% (61.6-75.6%) for the nasal Ag-RDT. With a viral load cut-off (≥ 5.2 log10 SARS-CoV-2 E-gene copies/mL) as a proxy of infectiousness, these sensitivities increased to 54.9% (46.4-63.3%) and 83.9% (76.9-89.5%), respectively. For the nasal Ag-RDT, sensitivities were 78.5% (71.1-84.8%) and 22.6% (9.6-41.1%) in those symptomatic and asymptomatic at the time of sampling, which increased to 90.4% (83.8-94.9%) and 38.9% (17.3-64.3%) after applying the viral load cut-off. In those with and without prior SARS-CoV-2 infection, sensitivities were 36.8% (16.3-61.6%) and 72.7% (65.1-79.4%). Specificities were > 99% and > 99%, positive predictive values > 70% and > 90%, and negative predictive values > 95% and > 95%, for the saliva and nasal Ag-RDT, respectively, in most analyses. Most participants considered the self-performing and result interpretation (very) easy for both self-tests. CONCLUSIONS: The Hangzhou AllTest Biotech saliva self Ag-RDT is not reliable for SARS-CoV-2 detection, overall, and in all studied subgroups. The SD Biosensor nasal self Ag-RDT had high sensitivity in individuals with symptoms and in those without prior SARS-CoV-2 infection but low sensitivity in asymptomatic individuals and those with a prior SARS-CoV-2 infection which warrants further investigation.

Accuracy of Rapid Antigen Detection Test Device (COVID-19 Ag Rapid Test Device) in Diagnosis of Acute COVID-19 Infections

Objective: To evaluate the accuracy of the COVID-19 Ag Rapid test device for detection of SARS-CoV-2 with Reverse Transcriptase Polymerase Chain Reaction as the gold standard. Study Design: Cross-sectional study. Place and Duration of Study: Department of Virology, Armed Forces Institute of Pathology, Rawalpindi, in the month of Sept 2020. Methodology: A total of 106 patients suspected of COVID-19 were tested, including 63 patients admitted to the COVID-19 ward of Pak Emirates Military Hospital and 43 from the emergency department of Combined Military Hospital, Rawalpindi Pakistan respectively. The samples were transported to the Virology department and subjected to Polymerase Chain Reaction and Antigen testing. In addition, the diagnostic accuracy of the COVID-19 Ag Rapid test device was compared to Reverse Transcriptase Polymerase Chain Reaction for detection of SARS-CoV-2 infection. Results: Out of 106 nasopharyngeal swab samples tested, 48 (45.2%) samples were positive by Rapid test device and Reversed Transcriptase Polymerase Chain Reaction, and 52 (49.0%) samples tested negative by both methods. Inconsistent results (False Negative) were obtained in 6 (5.6%) samples. COVID-19 Ag Rapid test device has detected the maximum number of cases, 41 (85.4%), during the first week of illness. Its sensitivity decreases as the duration of infection progress. Conclusion: The overall sensitivity of the Rapid test device is much less than the Polymerase chain reaction due to potential false negative results. However, it can be helpful in the early isolation of cases in an outbreak in a closed community and for case management in peripheral setups, where Polymerase chain reaction facilities are unavailable. © 2022, Army Medical College. All rights reserved.

Clinical sensitivity of rapid antigen test during a COVID-19 outbreak in Taipei, May to June 2021.

BACKGROUND/PURPOSE: This population-based study aimed to compare the accuracy of Rapid antigen detection (RAD) and reverse transcription-polymerase chain reaction (RT-PCR) assays for diagnosing individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the COVID-19 outbreak in Taipei, from May to June 2021. METHODS: In response to the outbreak of COVID-19 in mid-May 2021, Taipei City Hospital set up 12 citywide proactive community testing (PCT) stations for early identification of infected individuals from May 17 to June 20, 2021. Individuals with RAD positivity were isolated and later confirmed by RT-PCR. The c-statistic value was estimated to indicate the level of diagnostic accuracy of RAD tests. RESULTS: Of the 33,798 individuals who were evaluated for SARS-CoV-2 infection, 4.4% tested positive for RAD. There was a moderate concordance (kappa = 0.67) between the RAD tests and RT-PCR assay for identifying infectious individuals. The c-statistic value of the RAD test for the diagnosis of SARS-CoV-2 infection was 0.8. There was a positive linear trend between the accuracy of the RAD tests and the prevalence of SARS-CoV-2 infection in the study population (ß = 0.04; p = .03). As the cycle threshold value decreased, the sensitivity rate of the RAD tests increased (p < .001). After implementation of the PCT program, the prevalence of COVID-19 decreased from 8.4% to 3.3% (p < .001). CONCLUSION: Proactive community testing for SARS-CoV-2 infection using RAD tests could rapidly identify and quarantine the most infectious patients in the early phase of COVID-19 outbreak.

High Diagnostic Accuracy of a Novel Lateral Flow Assay for the Point-of-Care Detection of SARS-CoV-2.

Highly accurate lateral flow immunochromatographic tests (LFTs) are an important public health tool to tackle the ongoing COVID-19 pandemic. The aim of this study was to assess the comparative diagnostic performance of the novel ND COVID-19 LFT under real-world conditions. A total of 400 nasopharyngeal swab specimens with a wide range of viral loads were tested in both reverse-transcription polymerase chain reaction and ND LFT. The overall sensitivity and specificity were 85% (95% CI: 76.7-90.7%) and 100% (95% CI: 98.7-100%), respectively. There was a clear association between the false-negative rate and sample viral load: the sensitivity parameters for specimens with cycle threshold values of <25 (>3.95 × 106 copies/mL) and ≥30 (≤1.29 × 105 copies/mL) were 100% and 50%, respectively. The performance was maximized in testing samples with viral loads ≥1.29 × 105 copies/mL. These findings suggest that the ND LFT is sufficiently accurate and useful for mass population screening programs, especially in high-prevalence and resource-constrained settings or during periods when the epidemic curve is rising. Other public health implications were also discussed.

Evaluation of a Rapid Antigen Test for the Diagnosis of SARS-CoV-2 during the COVID-19 Pandemic.

OBJECTIVES: Reverse transcriptase-polymerase chain reaction (RT-PCR), the reference laboratory method of confirmed SARS-CoV-2 diagnosis, though requiring equipment, is time-consuming. There is a crucial demand for rapid techniques such as antigen detection test during the pandemic. This study assessed whether a rapid antigen detection (RAD) test was an effective and essential method for the early diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the COVID-19 pandemic. The probability of public screening at home and the application of RAD during the novel SARS-CoV-2 outbreak were also topics of interest. METHODS: A retrospective analysis based on the systemic screening for COVID-19 was conducted at Taipei City Hospital (TCH) from May 28 to June 06, 2021, the first week of outbreak in Taiwan. The results of the RAD and RT-PCR tests were collected from 5 major branches of the TCH. RESULTS: We collected a total number of 6368 cases. We found that the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy ranged from 60.5% to 78.6% (mean 66.0%), 98.2% to 99.9% (mean 99.0%), 74.4% to 97.8% (mean 82.8%), 94.0% to 98.4% (mean 97.5%), and 93.8% to 98.3% (mean 94.2%), respectively. Although the sensitivity score was not high (up to 95% or higher), the other results were satisfactory, with an accuracy of more than 93% in all branches. Furthermore, it had high specificity, PPV, NPV, and accuracy. CONCLUSION: We concluded that RAD could be a quick and feasible method to identify individuals infected with SARS-CoV-2 from non-contagious individuals during the COVID-19 outbreak. A RAD test was an effective and essential method for the early diagnosis of SARS-CoV-2 during the COVID-19 pandemic.

Validation of GeneFinder COVID-19 Ag Plus Rapid Test and Its Potential Utility to Slowing Infection Waves: A Single-Center Laboratory Evaluation Study.

Diagnostic laboratory tools are essential to keep everyone safe and track newly emerging variants; on the other hand, "filter" screening tests recognizing positivity are valuable tools to avoid hectic laboratory work that, besides COVID-19, are also part of the routine. Therefore, complementary assays, such as rapid antigen tests (RATs), are essential in controlling and monitoring virus spread within the community, especially in the asymptomatic population. A subset of nasopharyngeal swab specimens resulted in SARS-CoV-2 positive and investigated for genomic characterization were used for RAT validation. RATs were performed immediately after sampling, following the manufacturer's instructions (reading at 15 min). RT-PCRs were carried out within 24 h of specimens' collection. Out of 603 patients, 145 (24.05%) tested positive by RT-PCR and RAT and 451 (74.79%) tested negative by both methods; discordant results (RT-PCR+/RAT- or RT-PCR-/RAT+) were obtained in 7 patients (1.16%). RATs' overall specificity and sensitivity were 96.03% (95%CI: 91.55-98.53%) and 99.78% (95%CI: 98.77-99.99%), respectively, taking RT-PCR as the reference. Overall, RAT negative predictive value was 98.69% (95%CI 97.17-99.40%). The GeneFinder COVID-19 Ag Plus Rapid Test performed well as a screening test for early diagnosis of COVID-19, especially in asymptomatic subjects. The data suggested that patients with RT-PCR-proven COVID-19 testing negative by RAT are unlikely to be infectious. GeneFinder COVID-19 Ag Plus Rapid Test also works on variants of concern (VOC) delta and omicron BA.1 and BA.2.

Evaluation of rapid antigen detection kits for detection of SARS-CoV-2 B.1.617.2 virus.

Aim: Currently, there is lack of data regarding rapid antigen detection (RAD) kits to detect SARS-CoV-2 B.1.617.2 virus. Objective: The purpose of this evaluation is to assess analytical sensitivity of 12 RAD kits against SARS-CoV-2 B.1.617.2. Study design: Analytical sensitivity was determined by limit of detection (LOD). A serial tenfold dilution set from a respiratory specimen collected from a COVID-19 patient infected by SARS-CoV-2 B.1.617.2 was used. RT-PCR was used as a reference method. Results: The LOD results showed that 11 and one RAD kits were 100- and 1000-fold less sensitive than RT-PCR respectively. Conclusion: The results showed that the RAD kits evaluated in this study may be used for first-line screening of the SARS-CoV-2 B.1.617.2 variant.

Validation of rapid SARS-COV-2 antigen detection test as a screening tool for detection of Covid-19 infection at district hospital in northern India

Background: Testing of samples from suspected SARS-CoV-2 patients with reverse transcription polymerase chain reaction (RT-PCR) may result in delayed detection of infection. Given the number of people affected in pandemic, it is important to use a test that gives faster results and can be used on large number of sample size to cope with the increased testing capacity. Rapid Antigen detection test fulfills both the criteria. Aims and Objectives: The study aims to evaluate the diagnostic accuracy of rapid antigen detection test compared to RT-PCR on the same patients in District Hospital. Materials and Methods: Subjects were tested by both Rapid antigen detection testing and RT-PCR in District Hospital. The present study compared RAT and RT-PCR for detection of SARS-CoV-2 in nasopharyngeal specimen.756 Nasopharyngeal samples were obtained from suspected cases of SARS-CoV-2, Contacts of CoV2 patients, pre-operative patients in District Hospital. Results: Of 756 nasopharyngeal samples, 81 (10.71%) were positive and 675 (89.28%) were negative for SARS-CoV-2 by RT-PCR. The rapid SARS-CoV-2 antigen detection test's sensitivity 55.04% and specificity was 99.2%, respectively. Positive predictive value 93.42%, Negative predictive value 91.47%, Diagnostic Accuracy 91.67%, Cohen's Kappa Coefficient 0.6482, 95% CI: 0.5801-0.7163. Conclusion: The rapid antigen detection test showed comparable sensitivity and specificity with RT-PCR assay. These results support the fact that RAT is an accurate alternative to RT-PCR in areas where there is increased testing burden, for screening of asymptomatic carriers, in areas that lack suitable laboratories to perform RT-PCR, in areas such as airport, train stations, and bus stands. [ FROM AUTHOR] Copyright of Asian Journal of Medical Sciences is the property of Manipal Colleges of Medical Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Rapid growth in the COVID-19 era.

ABSTRACT: From Operation Warp Speed to the lipid mRNA vaccine, the COVID-19 pandemic has been a watershed moment for technological development, production, and implementation. The scale and pace of innovation and global collaboration has likely not been experienced since World War II. This article highlights some of the engineering accomplishments that occurred during the pandemic. We provide a broad overview of the technological achievements in vaccine design, antibody engineering, drug repurposing, and rapid diagnostic testing. We also discuss what the future of these technologies and the future of large-scale collaborations might look like moving forward.

Sensitivity and Specificity of SARS-CoV-2 Rapid Antigen Detection Tests Using Oral, Anterior Nasal, and Nasopharyngeal Swabs: a Diagnostic Accuracy Study.

The objective of our study was to evaluate the sensitivity and specificity of rapid antigen detection tests versus those of reverse transcriptase PCR (RT-PCR) using oral, anterior nasal, and nasopharyngeal swabs. The underlying prospective, diagnostic case-control-type accuracy study included 87 hospitalized and nonhospitalized participants in a positive and a negative sample cohort between 16 March and 14 May 2021 in two hospitals in Vienna. SARS-CoV-2 infection status was confirmed by RT-PCR. Participants self-performed one oral and one anterior nasal swab for the rapid antigen test, immediately followed by two nasopharyngeal swabs for the rapid antigen test and RT-PCR by the investigator. Test results were read after 15 min, and participants completed a questionnaire in the meantime. Test parameters were calculated based on the evaluation of 87 participants. The overall sensitivity of rapid antigen detection tests versus that of RT-PCR with oral, anterior nasal, and nasopharyngeal samples was 18.18% (95% confidence interval [CI] 8.19% to 32.71%), 63.04% (95% CI 47.55% to 76.79%), and 73.33% (95% CI 58.06% to 85.4%), respectively. All sampling methods had a test specificity of 100% regardless of the cycle threshold (CT) value. Rapid antigen detection tests using self-collected anterior nasal swabs proved to be as sensitive as and more tolerable than professionally collected nasopharyngeal swabs for CT values up to 30 determined by RT-PCR. This finding illustrates the reliability of tests obtained by adequate self-collected anterior nasal specimen. Sensitivity was dependent upon the CT value for each sampling method. While the main advantage of rapid antigen detection tests is the immediate availability of results, PCR should be preferred in crucial settings wherever possible. IMPORTANCE Rapid antigen detection devices for SARS-CoV-2 represent a valuable tool for monitoring the spread of infection. However, the reliability of the tests depends largely on the test performance and the respective sampling method. Nasopharyngeal swabs mark the gold standard for sample collection in suspected respiratory tract infections but are unsuitable for widespread application, as they must be performed by medically trained personnel. With the underlying study, the head-to-head test performance and the usability of self-collected samples for SARS-CoV-2 detection using rapid antigen detection devices were evaluated. The results confirm similar sensitivity of self-collected anterior nasal swabs to that of professionally collected nasopharyngeal swabs for patients with a CT of < 30 determined by RT-PCR.

Evaluation of Rapid Antigen Tests Using Nasal Samples to Diagnose SARS-CoV-2 in Symptomatic Patients.

INTRODUCTION: The best way to mitigate an outbreak besides mass vaccination is via early detection and isolation of infected cases. As such, a rapid, cost-effective test for the early detection of COVID-19 is required. METHODS: The study included 4,183 mildly symptomatic patients. A nasal and nasopharyngeal sample obtained from each patient was analyzed to determine the diagnostic ability of the rapid antigen detection test (RADT, nasal swab) in comparison with the current gold-standard (RT-PCR, nasopharyngeal swab). RESULTS: The calculated sensitivity and specificity of the RADT was 82.1 and 99.1%, respectively. Kappa's coefficient of agreement between the RADT and RT-PCR was 0.859 (p < 0.001). Stratified analysis showed that the sensitivity of the RADT improved significantly when lowering the cut-off RT-PCR Ct value to 24. CONCLUSION: Our study's results support the potential use of nasal swab RADT as a screening tool in mildly symptomatic patients, especially in patients with higher viral loads.