Project description:This guideline provides updated recommendations on the role of preprocedure testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) in individuals undergoing endoscopy in the post-vaccination period and replaces the prior guideline from the American Gastroenterological Association (AGA) (released July 29, 2020). Since the start of the pandemic, our increased understanding of transmission has facilitated the implementation of practices to promote patient and health care worker (HCW) safety. Simultaneously, there has been increasing recognition of the potential harm associated with delays in patient care, as well as inefficiency of endoscopy units. With widespread vaccination of HCWs and the general population, a re-evaluation of AGA's prior recommendations was warranted. In order to update the role of preprocedure testing for SARS-CoV2, the AGA guideline panel reviewed the evidence on prevalence of asymptomatic SARS-CoV2 infections in individuals undergoing endoscopy; patient and HCW risk of infections that may be acquired immediately before, during, or after endoscopy; effectiveness of COVID-19 vaccine in reducing risk of infections and transmission; patient and HCW anxiety; patient delays in care and potential impact on cancer burden; and endoscopy volumes. The panel considered the certainty of the evidence, weighed the benefits and harms of routine preprocedure testing, and considered burden, equity, and cost using the Grading of Recommendations Assessment, Development and Evaluation framework. Based on very low certainty evidence, the panel made a conditional recommendation against routine preprocedure testing for SARS-CoV2 in patients scheduled to undergo endoscopy. The panel placed a high value on minimizing additional delays in patient care, acknowledging the reduced endoscopy volumes, downstream impact on delayed cancer diagnoses, and burden of testing on patients.
Project description:Pediatric endoscopy has evolved into an indispensable tool in the diagnosis and management of gastrointestinal diseases in children. However, there is limited literature focusing on quality improvement initiatives in pediatric endoscopy. The primary goal of this project was to reduce the no-show rate in the pediatric endoscopy unit. Also, we aimed to improve patient and family satisfaction with the procedure by identifying opportunities for improvement. A checklist was designed based on the potential causes of no-show. The endoscopy nurse coordinator reviewed the checklist when scheduling the procedure to identify patients at high risk for non-compliance. Once a risk factor was identified, appropriate actions were taken. She also made a pre-procedure phone call as a reminder and to address any of these risks for non-compliance if present. A patient satisfaction survey was used to identify potential areas for improvement. The no-show rate decreased from an average of 7% in the pre-intervention phase to 2% in the post-intervention phase (p = 0.009). 91% of the patients/family recorded an overall satisfaction of 4 or 5 on a scale of 1-5 5 being best). Quality improvement strategies decreased the no-show rate in the pediatric endoscopy unit. A patient satisfaction survey helped in identifying areas for improvement.
Project description:We have developed a rapid, accurate, and cost-effective serologic test for SARS-CoV-2 virus, which caused the COVID-19 pandemic, on the basis of antibody-dependent agglutination of antigen-coated latex particles. When validated using plasma samples that are positive or negative for SARS-CoV-2, the agglutination assay detected antibodies against the receptor-binding domain of the spike (S-RBD) or the nucleocapsid protein of SARS-CoV-2 with 100% specificity and ∼98% sensitivity. Furthermore, we found that the strength of the S-RBD antibody response measured by the agglutination assay correlated with the efficiency of the plasma in blocking RBD binding to the angiotensin-converting enzyme 2 in a surrogate neutralization assay, suggesting that the agglutination assay might be used to identify individuals with virus-neutralizing antibodies. Intriguingly, we found that >92% of patients had detectable antibodies on the day of a positive viral RNA test, suggesting that the agglutination antibody test might complement RNA testing for the diagnosis of SARS-CoV-2 infection.
Project description:To safely re-open economies and prevent future outbreaks, rapid, frequent, point-of-need, SARS-CoV-2 diagnostic testing is necessary. However, existing field-deployable COVID-19 testing methods require the use of uncomfortable swabs and trained providers in PPE, while saliva-based methods must be transported to high complexity laboratories for testing. Here, we report the development and clinical validation of High-Performance Loop-mediated isothermal Amplification (HP-LAMP), a rapid, saliva-based, SARS-CoV-2 test with a limit of detection of 1.4 copies of virus per µl of saliva and a sensitivity and specificity with clinical samples of > 96%, on par with traditional RT-PCR based methods using swabs, but can deliver results using only a single fluid transfer step and simple heat block. Testing of 120 patient samples in 40 pools comprised of 5 patient samples each with either all negative or a single positive patient sample was 100% accurate. Thus, HP-LAMP may enable rapid and accurate results in the field using saliva, without need of a high-complexity laboratory.
Project description:BackgroundTesting used in screening, diagnosis and follow-up of COVID-19 has been a subject of debate. Several organisations have developed formal advice about testing for COVID-19 to assist in the control of the disease. We collated, delineated and appraised current worldwide recommendations about the role and applications of tests to control SARS-CoV-2/COVID-19.MethodsWe searched for documents providing recommendations for COVID-19 testing in PubMed, EMBASE, LILACS, the Coronavirus Open Access Project living evidence database and relevant websites such as TRIP database, ECRI Guidelines Trust, the GIN database, from inception to 21 September 2020. Two reviewers applied the eligibility criteria to potentially relevant citations without language or geographical restrictions. We extracted data in duplicate, including assessment of methodological quality using the Appraisal of Guidelines for Research and Evaluation-II tool.ResultsWe included 47 relevant documents and 327 recommendations about testing. Regarding the quality of the documents, we found that the domains with the lowest scores were 'Editorial independence' (Median=4%) and 'Applicability' (Median=6%). Only six documents obtained at least 50% score for the 'Rigour of development' domain. An important number of recommendations focused on the diagnosis of suspected cases (48%) and deisolation measures (11%). The most frequently recommended test was the reverse transcription-PCR (RT-PCR) assay (87 recommendations) and the chest CT (38 recommendations). There were 22 areas of agreement among guidance developers, including the use of RT-PCR for SARS-Cov-2 confirmation, the limited role of bronchoscopy, the use chest CT and chest X-rays for grading severity and the co-assessment for other respiratory pathogens.ConclusionThis first scoping review of recommendations for COVID-19 testing showed many limitations in the methodological quality of included guidance documents that could affect the confidence of clinicians in their implementation. Future guidance documents should incorporate a minimum set of key methodological characteristics to enhance their applicability for decision making.
Project description:Rapid antigen tests (RATs) are widely used for point-of-care or self-testing to identify SARS-CoV-2 (SCoV2), but currently circulating Omicron variants may impair detection. In this study, we prospectively evaluated the Roche-SARS-CoV-2-Antigen and Acon-FlowFlex-SARS-CoV-2-Antigen in 150 consecutively collected nasopharyngeal patient swabs (50 SCoV2 RNA undetectable; 100 SCoV2 Omicron BA.1). Omicron BA.1 results were compared to 92 Ct-matched early-pandemic SCoV2 variants (B.1.160 and B.1.177), to 100 Omicron BA.2 positive and to 100 Omicron BA.5 positive samples. For Omicron BA.1, Roche-SARS-CoV-2-Antigen detected 87% of samples having Ct-values <29 reflecting 3.6% lower rates compared to B.1.160 and B.1.177. Acon-FlowFlex-SARS-CoV-2-Antigen was less affected and detected 90% of Omicron BA.1 with Ct-values <29. Omicron BA.2 and BA.5 detection rates were significantly reduced by 20% and 10%, respectively, for the Roche-SARS-CoV-2-Antigen in samples with Ct-values <29 but remained similar for Acon-FlowFlex-SARS-CoV-2-Antigen. RATs need to be continuously evaluated as new SCoV2-variants emerge. Spreading of Omicron-BA.2, and the recently emerged Omicron BA.5 variant, may not only result from escape from postvaccine or postinfection immunity, but also from false-negative RATs misguiding point-of-care and self-testing decisions at times of restricted molecular testing. IMPORTANCE Antigen tests are widely used for rapid identification of SCoV2-positive cases and their increased risk of transmission. At present, there are several FDA- and CE-cleared tests available in North America and Europe. However, their diagnostic performance has been evaluated with early-pandemic variants. This study provides evidence that variation within the nucleocapsid protein as seen in recently emerged and now globally spreading Omicron BA.2 and BA.5 variants significantly impairs detection rates of widely used antigen tests. Consequently, antigen tests need to be reevaluated when new pandemic SCoV2 variants emerge and start to predominate globally.
Project description:BackgroundOver the course of the COVID-19 pandemic, laboratories worldwide have been facing an unprecedented increase in demand for PCR testing because of the high importance of diagnostics for prevention and control of virus spread. Moreover, testing demand has been varying considerably over time, depending on the epidemiological situation, rendering efficient resource allocation difficult. Here, we present a scalable workflow which we implemented in our laboratory to increase PCR testing capacity while maintaining high flexibility regarding the number of samples to be processed.MethodsWe compared the performance of five automated extraction instruments, using dilutions of SARS-CoV-2 cell culture supernatant as well as clinical samples. To increase PCR throughput, we combined the two duplex PCR reactions of our previously published SARS-CoV-2 PCR assay into one quadruplex reaction and compared their limit of detection as well as their performance on the detection of low viral loads in clinical samples. Furthermore, we developed a sample pooling protocol with either two or four samples per pool, combined with a specifically adapted SARS-CoV-2 quadruplex PCR assay, and compared the diagnostic sensitivity of pooled testing and individual testing.ResultsAll tested automated extraction instruments yielded comparable results regarding the subsequent sensitivity of SARS-CoV-2 detection by PCR. While the limit of detection of the quadruplex SARS-CoV-2 PCR assay (E-Gene assay: 28.7 genome equivalents (ge)/reaction, orf1ab assay: 32.0 ge/reaction) was slightly higher than that of our previously published duplex PCR assays (E-Gene assay: 9.8 ge/reaction, orf1ab assay: 6.6 ge/reaction), the rate of correctly identified positive patient samples was comparable for both assays. Sample pooling with optimized downstream quadruplex PCR showed no loss in diagnostic sensitivity compared to individual testing.ConclusionSpecific adaptation of PCR assays can help overcome the potential loss of sensitivity due to higher levels of PCR multiplexing or sample dilution in pooled testing. Combining these adapted PCR assays with different sample processing strategies provides a simple and highly adjustable workflow for resource-efficient SARS-CoV-2 diagnostics. The presented principles can easily be adopted in a variety of laboratory settings as well as be adapted to pathogens other than SARS-CoV-2, making it feasible for any laboratory that conducts PCR diagnostics.
Project description:BackgroundThe durability of the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination remains unknown. The objective of this study was to evaluate a rapid SARS-CoV-2 IgM/IgG antibody detection kit as a qualitative screen for the humoral response to vaccination.MethodsStudy participants (n = 125) included pediatric healthcare workers (HCWs) who had received two doses of BNT162b2 or mRNA-1273. Participants were tested on study entry (March 12, 2021 to April 9, 2021). The mean number of days post second dose was 22 (range 17-36). Participants were tested for IgM/IgG antibodies to the SARS-CoV-2 spike protein with the RightSign COVID-19 IgG/IgM Rapid Test Cassette. ELISA/competitive inhibition ELISA (CI-ELISA) were subsequently run to assess for the neutralization effect and SARS-CoV-2 anti-nucleocapsid IgM/IgG antibodies.ResultsOverall, 98.4% of participants were IgG-positive and 0.8% were IgM-positive on rapid RightSign testing. Of those with IgG-positive results, 100% were anti-spike protein IgG-positive on CI-ELISA; none of those who tested IgG-negative via the rapid test were IgG-positive on CI-ELISA. All HCWs who tested RightSign positive demonstrated neutralizing capability on CI-ELISA. Overall, 1.6% demonstrated anti-nucleocapsid IgM antibodies and 5.6% demonstrated anti-nucleocapsid IgG antibodies.ConclusionsThe strong agreement between the rapid RightSign IgG results and confirmatory CI-ELISA testing suggests that this test may be used to assess for positive, and neutralizing, antibody responses to SARS-CoV-2 mRNA vaccination.