Question: what types of rapid testing for Covid-19 have been developed?

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

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

Title: Optimization of the CDC Protocol of Molecular Diagnosis of COVID-19 for Timely Diagnosis Content: Coronavirus disease 2019 (COVID-19), the current uncontrolled outbreak of infectious disease, has caused significant challenges throughout the world. A reliable rapid diagnostic test for COVID-19 is demanded worldwide. The real-time reverse transcriptase polymerase chain was one of the most quickly established methods in the novel viral pandemic and was considered as the gold standard for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this report, we illustrate our experience of applying a protocol from the Taiwan CDC and achieving assay optimization in the immediate circumstances to meet the urgent medical and public health needs.

Title: Sensitivity and specificity of a rapid test for assessment of exposure to SARS-CoV-2 in a community-based setting in Brazil Content: Background: While the recommended laboratory diagnosis of COVID-19 is a molecular based assay, population-based studies to determine the prevalence of COVID-19 usually use serological assays. Objective: To evaluate the sensitivity and specificity of a rapid diagnostic test for COVID-19 compared to quantitative reverse transcription polymerase chain reaction (qRT-PCR). Methods: We evaluated the sensitivity using a panel of finger prick blood samples from participants >18 years of age that had been tested for COVID-19 by qRT-PCR. For assessing specificity, we used serum samples from the 1982 Pelotas (Brazil) Birth Cohort participants collected in 2012 with no exposure to SARS-CoV-2. Results: The sensitivity of the test was 77.1% (95% CI 66.6 - 85.6), based upon 83 subjects who had tested positive for qRT-PCR at least 10 days before the rapid diagnostic test (RDT). Based upon 100 sera samples, specificity was 98.0% (95% CI 92.9 - 99.8). There was substantial agreement (Kappa score 0.76) between the qRT-PCR results and the RDT. Interpretation. The validation results are well in line with previous assessments of the test, and confirm that it is sufficiently precise for epidemiological studies aimed at monitoring levels and trends of the COVID-19 pandemic.

Title: Diagnostic Performance of a Rapid Point of Care Test for SARS-CoV-2 in an Urban ED Setting Content: The ability to rapidly and accurately identify a patient's COVID-19 status has had significant impact on emergency departments (ED) and health systems globally. Since the identification of SARS-CoV-2 illness in the United States, there has been rapid development in patient testing capacity following initial challenges including sparse availability. This was made possible by increasing availability of diagnostic molecular tests in several formats, from laboratory based traditional, RT-PCR methods to near patient testing rapid point of care PCR tests.

Title: Evaluation of a COVID-19 IgM and IgG rapid test; an efficient tool for assessment of past exposure to SARS-CoV-2 Content: COVID-19 is the most rapidly growing pandemic in modern time, and the need for serological testing is most urgent. Although the diagnostics of acute patients by RT-PCR is both efficient and specific, we are also crucially in need of serological tools for investigating antibody responses and assessing individual and potential herd immunity. We evaluated a commercially available test developed for rapid (within 15 minutes) detection of SARS-CoV-2-specific IgM and IgG by 29 PCR-confirmed COVID-19 cases and 124 negative controls. The results revealed a sensitivity of 69% and 93.1% for IgM and IgG, respectively, based solely on PCR-positivity due to the absence of a serological gold standard. The assay specificities were shown to be 100% for IgM and 99.2% for IgG. This indicates that the test is suitable for assessing previous virus exposure, although negative results may be unreliable during the first weeks after infection. More detailed studies on antibody responses during and post infection are urgently needed.

Title: Diagnostic Performance of a Rapid Point of Care Test for SARS‐CoV‐2 in an Urban ED Setting Content: The ability to rapidly and accurately identify a patient's COVID‐19 status has had significant impact on emergency departments (ED) and health systems globally. Since the identification of SARS‐CoV‐2 illness in the United States, there has been rapid development in patient testing capacity following initial challenges including sparse availability. This was made possible by increasing availability of diagnostic molecular tests in several formats, from laboratory based traditional, RT‐PCR methods to near patient testing rapid point of care PCR tests.

Title: ¿Conocemos las propiedades diagnósticas de las pruebas usadas en COVID-19? Una revisión rápida de la literatura recientemente publicada./ ¿Conocemos las propiedades diagnósticas de las pruebas usadas en COVID-19? Una revisión rápida de la literatura recientemente publicada./ Do we know the diagnostic properties of the tests used in COVID-19? A rapid review of recently published literature Content: COVID-19 has brought death and disease to large parts of the world. Governments must deploy strategies to screen the population and subsequently isolate the suspect cases. Diagnostic testing is critical for epidemiological surveillance, but the accuracy (sensitivity and specificity) and clinical utility (impact on health outcomes) of the current diagnostic methods used for SARS-CoV-2 detection are not known. I ran a quick search in PubMed/MEDLINE to find studies on laboratory diagnostic tests and rapid viral diagnosis. After running the search strategies, I found 47 eligible articles that I discuss in this review, commenting on test characteristics and limitations. I did not find any papers that report on the clinical utility of the tests currently used for COVID-19 detection, meaning that we are fighting a battle without proper knowledge of the proportion of false negatives that current testing is resulting in. This shortcoming should not be overlooked as it might hamper national efforts to contain the pandemic through testing community-based suspect cases.

Title: Do we know the diagnostic properties of the tests used in COVID-19? A rapid review of recently published literature. Content: COVID-19 has brought death and disease to large parts of the world. Governments must deploy strategies to screen the population and subsequently isolate the suspect cases. Diagnostic testing is critical for epidemiological surveillance, but the accuracy (sensitivity and specificity) and clinical utility (impact on health outcomes) of the current diagnostic methods used for SARS-CoV-2 detection are not known. I ran a quick search in PubMed/MEDLINE to find studies on laboratory diagnostic tests and rapid viral diagnosis. After running the search strategies, I found 47 eligible articles that I discuss in this review, commenting on test characteristics and limitations. I did not find any papers that report on the clinical utility of the tests currently used for COVID-19 detection, meaning that we are fighting a battle without proper knowledge of the proportion of false negatives that current testing is resulting in. This shortcoming should not be overlooked as it might hamper national efforts to contain the pandemic through testing community-based suspect cases.

Title: Rapid Detection of Novel Coronavirus (COVID-19) by Reverse Transcription-Loop-Mediated Isothermal Amplification Content: Novel Corona virus (COVID-19 or 2019-nCoV) is an emerging global health concern that requires a rapid diagnostic test. Quantitative reverse transcription PCR (qRT-PCR) is currently the standard for COVID-19 detection; however, Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP) may allow for faster and cheaper field based testing at point-of-risk. The objective of this study was to develop a rapid screening diagnostic test that could be completed in under 30 minutes. Simulated patient samples were generated by spiking serum, urine, saliva, oropharyngeal swabs, and nasopharyngeal swabs with a portion of the COVID-19 nucleic sequence. The samples were tested using RT-LAMP as well as by conventional qRT-PCR. Specificity of the RT-LAMP was evaluated by also testing against other related coronaviruses. RT-LAMP specifically detected COVID-19 in simulated patient samples. This test was performed in under 30 minutes. This approach could be used for monitoring of exposed individuals or potentially aid with screening efforts in the field and potential ports of entry.

Title: Overcoming the bottleneck to widespread testing: a rapid review of nucleic acid testing approaches for COVID-19 detection Content: The current COVID-19 pandemic presents a serious public health crisis, and a better understanding of the scope and spread of the virus would be aided by more widespread testing. Nucleic-acid-based tests currently offer the most sensitive and early detection of COVID-19. However, the "gold standard" test pioneered by the U.S. Centers for Disease Control and Prevention takes several hours to complete and requires extensive human labor, materials such as RNA extraction kits that could become in short supply, and relatively scarce qPCR machines. It is clear that a huge effort needs to be made to scale up current COVID-19 testing by orders of magnitude. There is thus a pressing need to evaluate alternative protocols, reagents, and approaches to allow nucleic-acid testing to continue in the face of these potential shortages. There has been a tremendous explosion in the number of papers written within the first weeks of the pandemic evaluating potential advances, comparable reagents, and alternatives to the "gold-standard" CDC RT-PCR test. Here we present a collection of these recent advances in COVID-19 nucleic acid testing, including both peer-reviewed and preprint articles. Due to the rapid developments during this crisis, we have included as many publications as possible, but many of the cited sources have not yet been peer-reviewed, so we urge researchers to further validate results in their own laboratories. We hope that this review can urgently consolidate and disseminate information to aid researchers in designing and implementing optimized COVID-19 testing protocols to increase the availability, accuracy, and speed of widespread COVID-19 testing.

Title: Diagnostic performance of COVID-19 serology assays Content: INTRODUCTION: The World Health Organization (WHO) declared COVID-19 outbreak as a world pandemic on 12th March 2020. Diagnosis of suspected cases is confirmed by nucleic acid assays with real-time PCR, using respiratory samples. Serology tests are comparatively easier to perform, but their utility may be limited by the performance and the fact that antibodies appear later during the disease course. We aimed to describe the performance data on serological assays for COVID-19. MATERIALS AND METHODS: A review of multiple reports and kit inserts on the diagnostic performance of rapid tests from various manufacturers that are commercially available were performed. Only preliminary data are available currently. RESULTS: From a total of nine rapid detection test (RDT) kits, three kits offer total antibody detection, while six kits offer combination SARS-CoV-2 IgM and IgG detection in two separate test lines. All kits are based on colloidal gold-labeled immunochromatography principle and one-step method with results obtained within 15 minutes, using whole blood, serum or plasma samples. The sensitivity for both IgM and IgG tests ranges between 72.7% and 100%, while specificity ranges between 98.7% to 100%. Two immunochromatography using nasopharyngeal or throat swab for detection of COVID-19 specific antigen are also reviewed. CONCLUSIONS: There is much to determine regarding the value of serological testing in COVID-19 diagnosis and monitoring. More comprehensive evaluations of their performance are rapidly underway. The use of serology methods requires appropriate interpretations of the results and understanding the strengths and limitations of such tests.

Title: Current and emerging diagnostic tests available for the novel COVID-19 global pandemic Content: On March 11, 2020 the World Health Organization (WHO) upgraded the status of the coronavirus disease 2019 (COVID-19) outbreak from epidemic to a global pandemic. This infection is caused by a novel coronavirus, SARS-CoV-2. Several rapid diagnostic tests have been developed at an astonishing pace; however, COVID-19 requires more highly specific rapid point-of-care diagnostic tests. This review describes the currently available testing approaches, as well as the available test assays including the Xpert® Xpress SARS-CoV-2 test (takes (~)45 min) and Abbott ID COVID-19 test (5 min) as easy to use point-of-care tests for diagnosis of novel COVID-19 that have so far received the US Food and Drug Administration emergency use authorizations clearance. This review is correct as of the date published and will be updated as more diagnostic tests come to light.

Title: Rapid point-of-care testing for SARS-CoV-2 in a community screening setting shows low sensitivity Content: OBJECTIVE: With the current SARS-CoV2 outbreak, countless tests need to be performed on potential symptomatic individuals, contacts and travellers. The gold standard is a quantitative polymerase chain reaction (qPCR)-based system taking several hours to confirm positivity. For effective public health containment measures, this time span is too long. We therefore evaluated a rapid test in a high-prevalence community setting. STUDY DESIGN: Thirty-nine randomly selected individuals at a COVID-19 screening centre were simultaneously tested via qPCR and a rapid test. Ten previously diagnosed individuals with known SARS-CoV-2 infection were also analysed. METHODS: The evaluated rapid test is an IgG/IgM-based test for SARS-CoV-2 with a time to result of 20 min. Two drops of blood are needed for the test performance. RESULTS: Of 49 individuals, 22 tested positive by repeated qPCR. In contrast, the rapid test detected only eight of those positive correctly (sensitivity: 36.4%). Of the 27 qPCR-negative individuals, 24 were detected correctly (specificity: 88.9%). CONCLUSION: Given the low sensitivity, we recommend not to rely on an antibody-based rapid test for public health measures such as community screenings.

Title: Overcoming the bottleneck to widespread testing: A rapid review of nucleic acid testing approaches for COVID-19 detection. Content: The current COVID-19 pandemic presents a serious public health crisis, and a better understanding of the scope and spread of the virus would be aided by more widespread testing. Nucleic-acid based tests currently offer the most sensitive and early detection of COVID-19. However, the "gold standard" test pioneered by the United States Center for Disease Control & Prevention, takes several hours to complete and requires extensive human labor, materials such as RNA extraction kits that could become in short supply and relatively scarce qPCR machines. It is clear that a huge effort needs to be made to scale up current COVID-19 testing by orders of magnitude. There is thus a pressing need to evaluate alternative protocols, reagents, and approaches to allow nucleic-acid testing to continue in the face of these potential shortages. There has been a tremendous explosion in the number of papers written within the first weeks of the pandemic evaluating potential advances, comparable reagents, and alternatives to the "gold-standard" CDC RT-PCR test. Here we present a collection of these recent advances in COVID-19 nucleic acid testing, including both peer-reviewed and preprint articles. Due to the rapid developments during this crisis, we have included as many publications as possible, but many of the cited sources have not yet been peer-reviewed, so we urge researchers to further validate results in their own labs. We hope that this review can urgently consolidate and disseminate information to aid researchers in designing and implementing optimized COVID-19 testing protocols to increase the availability, accuracy, and speed of widespread COVID-19 testing.

Title: Evaluation of eleven rapid tests for detection of antibodies against SARS-CoV-2 Content: Objectives SARS-CoV-2, causing COVID-19, has emerged to cause a human pandemic. Detection of SARS-CoV-2 in respiratory samples by using PCR is the standard laboratory diagnostic tool. Our aim was to perform a limited evaluation of the diagnostic performance and user-friendliness of eleven rapid tests for detection of antibodies against SARS-CoV-2. Methods All participants were tested with PCR against SARS-CoV-2 at a clinical microbiology laboratory. Comparing with results from PCR tests, we evaluated the rapid tests' performances in three arms; 1) 20 hospitalized patients with PCR-confirmed COVID-19, 2) 23 recovered outpatients with former PCR-confirmed COVID-19, and 3) 49 participants with suspected COVID-19 presenting at a primary care emergency room. Results All eleven tests detected antibodies in hospitalized COVID-19 patients, though with varying sensitivities. In former outpatients recovered from COVID-19, there were differences between tests in the immunoglobulin type G (IgG) sensitivity, with five tests having a sensitivity below 65%. In participants with suspected COVID-19 infection, the rapid tests had very low sensitivities. Most rapid tests were easy to perform and interpret. Conclusions Rapid tests were not suited as stand-alone tests to detect present infection in a Norwegian primary care emergency room population. All the rapid tests were able to detect SARS-CoV-2 antibodies, although sensitivities varied and were generally higher in the study arm of more severely affected participants. Rapid tests with high IgG sensitivity (and specificity) may be useful for confirmation of past infection. An independent evaluation should be performed in the intended population before introducing a rapid test.

Title: Evaluation of eleven rapid tests for detection of antibodies against SARS-CoV-2. Content: Objectives SARS-CoV-2, causing COVID-19, has emerged to cause a human pandemic. Detection of SARS-CoV-2 in respiratory samples by using PCR is the standard laboratory diagnostic tool. Our aim was to perform a limited evaluation of the diagnostic performance and user-friendliness of eleven rapid tests for detection of antibodies against SARS-CoV-2. Methods All participants were tested with PCR against SARS-CoV-2 at a clinical microbiology laboratory. Comparing with results from PCR tests, we evaluated the rapid tests' performances in three arms; 1) 20 hospitalized patients with PCR-confirmed COVID-19, 2) 23 recovered outpatients with former PCR-confirmed COVID-19, and 3) 49 participants with suspected COVID-19 presenting at a primary care emergency room. Results All eleven tests detected antibodies in hospitalized COVID-19 patients, though with varying sensitivities. In former outpatients recovered from COVID-19, there were differences between tests in the immunoglobulin type G (IgG) sensitivity, with five tests having a sensitivity below 65%. In participants with suspected COVID-19 infection, the rapid tests had very low sensitivities. Most rapid tests were easy to perform and interpret. Conclusions Rapid tests were not suited as stand-alone tests to detect present infection in a Norwegian primary care emergency room population. All the rapid tests were able to detect SARS-CoV-2 antibodies, although sensitivities varied and were generally higher in the study arm of more severely affected participants. Rapid tests with high IgG sensitivity (and specificity) may be useful for confirmation of past infection. An independent evaluation should be performed in the intended population before introducing a rapid test.

Title: Trends and Innovations in Biosensors for COVID-19 Mass Testing Content: Fast and widespread diagnosis is crucial to fighting against the outbreak of COVID-19. This work surveys the landscape of available and emerging biosensor technologies for COVID-19 testing. Molecular diagnostic assays based on quantitative reverse transcription polymerase chain reaction are used in most clinical laboratories. However, the COVID-19 pandemic has overwhelmed testing capacity and motivated the development of fast point-of-care tests and the adoption of isothermal DNA amplification. Antigenic and serological rapid tests based on lateral-flow immunoassays suffer from low sensitivity. Advanced digital systems enhance performance at the expense of speed and the need for large equipment. Emerging technologies, including CRISPR gene-editing tools, benefit from high sensitivity and specificity of molecular diagnostics and the easy use of lateral-flow assays. DNA sequencing and sample pooling strategies are highlighted to bring out the full capacity of the available biosensor technologies and accelerate mass testing.

Title: Trends and innovations in biosensors for COVID-19 mass testing. Content: Fast and widespread diagnosis is crucial to fight against the outbreak of COVID-19. The present work surveys the landscape of available and emerging biosensor technologies for COVID-19 testing. Molecular diagnostic assays based on quantitative Reverse Transcription Polymerase Chain Reaction are used in most clinical laboratories. The COVID-19 pandemic has overwhelmed the testing capacity and motivated the development of fast point-of-care tests and the adoption of isothermal DNA amplification. Antigenic and serological rapid tests based on lateral flow immunoassays suffer from low sensitivity. Advanced digital systems enhance the performance at the expense of speed and large equipment requirement. Emerging technologies, including CRISPR gene-editing tools, benefit from high sensitivity and selectivity of molecular diagnostics and the easy use of lateral flow assays. DNA sequencing and sample pooling strategies are highlighted to bring out the full capacity of the available biosensor technologies and accelerate mass testing.

Title: Fast SARS-CoV-2 detection by RT-qPCR in preheated nasopharyngeal swab samples Content: The current reference for COVID-19 diagnosis is based on the detection of SARS-CoV-2 on RNA extracts using one-step retrotranscription and quantitative PCR (RT-qPCR). Based on the urgent need for high-throughput COVID-19 screening, we tested the performance of three alternative, simple and affordable protocols to rapidly detect SARS-CoV-2, overcoming the long and tedious RNA extraction step. Although with an average increase of 6.1 ( ±1.6) cycles compared to standard tests with RNA extracts, we show that RT-qPCR yielded consistent results in nasopharyngeal swab samples that were subject to a direct 70°C incubation for 10 min. Our findings provide viable options to overcome any supply chain issue and help to increase the throughput of diagnostic tests by using any qPCR device, thereby complementing standard COVID-19 testing.

Title: Diagnostic performance of COVID-19 serology assays. Content: INTRODUCTION The World Health Organization (WHO) declared COVID-19 outbreak as a world pandemic on 12th March 2020. Diagnosis of suspected cases is confirmed by nucleic acid assays with real-time PCR, using respiratory samples. Serology tests are comparatively easier to perform, but their utility may be limited by the performance and the fact that antibodies appear later during the disease course. We aimed to describe the performance data on serological assays for COVID-19. MATERIALS AND METHODS A review of multiple reports and kit inserts on the diagnostic performance of rapid tests from various manufacturers that are commercially available were performed. Only preliminary data are available currently. RESULTS From a total of nine rapid detection test (RDT) kits, three kits offer total antibody detection, while six kits offer combination SARS-CoV-2 IgM and IgG detection in two separate test lines. All kits are based on colloidal gold-labeled immunochromatography principle and one-step method with results obtained within 15 minutes, using whole blood, serum or plasma samples. The sensitivity for both IgM and IgG tests ranges between 72.7% and 100%, while specificity ranges between 98.7% to 100%. Two immunochromatography using nasopharyngeal or throat swab for detection of COVID-19 specific antigen are also reviewed. CONCLUSIONS There is much to determine regarding the value of serological testing in COVID-19 diagnosis and monitoring. More comprehensive evaluations of their performance are rapidly underway. The use of serology methods requires appropriate interpretations of the results and understanding the strengths and limitations of such tests.

Title: A handheld point-of-care system for rapid detection of SARS-CoV-2 in under 20 minutes Content: The COVID-19 pandemic is a global health emergency characterized by the high rate of transmission and ongoing increase of cases globally. Rapid point-of-care (PoC) diagnostics to detect the causative virus, SARS-CoV-2, are urgently needed to identify and isolate patients, contain its spread and guide clinical management. In this work, we report the development of a rapid PoC diagnostic test (< 20 min) based on reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) and semiconductor technology for the detection of SARS-CoV-2 from extracted RNA samples. The developed LAMP assay was tested on a real-time benchtop instrument (RT-qLAMP) showing a lower limit of detection of 10 RNA copies per reaction. It was validated against 183 clinical samples including 127 positive samples (screened by the CDC RT-qPCR assay). Results showed 90.55% sensitivity and 100% specificity when compared to RT-qPCR and average positive detection times of 15.45 {+/-} 4.43 min. For validating the incorporation of the RT-LAMP assay onto our PoC platform (RT-eLAMP), a subset of samples was tested (n=40), showing average detection times of 12.89 {+/-} 2.59 min for positive samples (n=34), demonstrating a comparable performance to a benchtop commercial instrument. Paired with a smartphone for results visualization and geo-localization, this portable diagnostic platform with secure cloud connectivity will enable real-time case identification and epidemiological surveillance.

Title: Clinical meanings of rapid serological assay in patients tested for SARS-Co2 RT-PCR Content: Background RT-PCR test for identifiction of viral nucleic acid is the current standard diagnostic method for the diagnosis of COVID-19 disease but technical reasons limit the utilization of this assay on large scale screenings. Method We verified in a consecutive series of 191 symptomatic patients the clinical information that new rapid serological colorimetric test qualitatively analyzing IgM/IgG expression can provide with respect to standard assay and with respect to clinical outcome of patients. Results Rapid serological test showed a sensitivity of 30% and a specificity of 89% with respect to the standard assay but, interestingly, these performances improve after 8 days of symptoms appearance. After 10 days of symptoms the predictive value of rapid serological test is higher than that of standard assay. When the behaviour of the two immunoglobulins was evaluated with respect to time length of symptoms appearance, no significant difference in immunoglobulins behaviour was shown. Conclusions The rapid serological test analyzed in the present study is candidate to provide information on immunoreaction of the subject to COVID-19 exposure.

Title: Rapid point-of-care testing for SARS-CoV-2 in a community screening setting shows low sensitivity Content: Abstract Objective With the current SARS-CoV2 outbreak, countless tests need to be performed on potential symptomatic individuals, contacts and travellers. The gold standard is a quantitative polymerase chain reaction (qPCR)–based system taking several hours to confirm positivity. For effective public health containment measures, this time span is too long. We therefore evaluated a rapid test in a high-prevalence community setting. Study design Thirty-nine randomly selected individuals at a COVID-19 screening centre were simultaneously tested via qPCR and a rapid test. Ten previously diagnosed individuals with known SARS-CoV-2 infection were also analysed. Methods The evaluated rapid test is an IgG/IgM–based test for SARS-CoV-2 with a time to result of 20 min. Two drops of blood are needed for the test performance. Results Of 49 individuals, 22 tested positive by repeated qPCR. In contrast, the rapid test detected only eight of those positive correctly (sensitivity: 36.4%). Of the 27 qPCR-negative individuals, 24 were detected correctly (specificity: 88.9%). Conclusion Given the low sensitivity, we recommend not to rely on an antibody-based rapid test for public health measures such as community screenings.

Title: Multi-Tiered Screening and Diagnosis Strategy for COVID-19: A Model for Sustainable Testing Capacity in Response to Pandemic. Content: Coronavirus disease 2019 (COVID-19), caused by novel enveloped single stranded RNA coronavirus (SARS-CoV-2), is responsible for an ongoing global pandemic. While other countries deployed widespread testing as an early mitigation strategy, the U.S. experienced delays in development and deployment of organism identification assays. As such, there is uncertainty surrounding disease burden and community spread, severely hampering containment efforts. COVID-19 illuminates the need for a tiered diagnostic approach to rapidly identify clinically significant infections and reduce disease spread. Without the ability to efficiently screen patients, hospitals are overwhelmed, potentially delaying treatment for other emergencies.A multi-tiered, diagnostic strategy incorporating a rapid host immune response assay as a screening test; molecular confirmatory testing and rapid IgM/IgG testing to assess benefit from quarantine/further testing and provide information on population exposure/herd immunity would efficiently evaluate potential COVID-19 patients. Triaging patients within minutes with a fingerstick rather than hours/days after an invasive swab is critical to pandemic response as reliance on the existing strategy is limited by assay accuracy, time to results, and testing capacity. Early screening and triage is achievable from the outset of a pandemic with point-of-care host immune response testing which will improve response time to clinical and public health actions. Key MessagesDelayed testing deployment has led to uncertainty surrounding overall disease burden and community spread, severely hampering public health containment and healthcare system preparation efforts.A multi-tiered testing strategy incorporating rapid, host immune point-of-care tests can be used now and for future pandemic planning by effectively identifying patients at risk of disease thereby facilitating quarantine earlier in the progression of the outbreak during the weeks and months it can take for pathogen specific confirmatory tests to be developed, validated and manufactured in sufficient quantities.The ability to triage patients at the point of care and support the guidance of medical and therapeutic decisions, for viral isolation or confirmatory testing or for appropriate treatment of COVID-19 and/or bacterial infections, is a critical component to our national pandemic response and there is an urgent need to implement the proposed strategy to combat the current outbreak.

Title: Testing for SARS-CoV-2 (COVID-19): a systematic review and clinical guide to molecular and serological in-vitro diagnostic assays Content: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated coronavirus disease 2019 (COVID-19) pandemic has demanded rapid upscaling of in-vitro diagnostic assays to enable mass screening and testing of high-risk groups, and simultaneous ascertainment of robust data on past SARS-CoV-2 exposure at an individual and a population level. To meet the exponential demand in testing, there has been an accelerated development of both molecular and serological assays across a plethora of platforms. The present review discusses the current literature on these modalities, including nucleic acid amplification tests, direct viral antigen tests and the rapidly expanding laboratory-based and point of care serological tests. This suite of complementary tests will inform crucial decisions by healthcare providers and policy makers, and understanding their strengths and limitations will be critical to their judicious application for the development of algorithmic approaches to treatment and public health strategies.

Title: Multi-tiered screening and diagnosis strategy for COVID-19: a model for sustainable testing capacity in response to pandemic Content: Coronavirus disease 2019 (COVID-19), caused by novel enveloped single stranded RNA coronavirus (SARS-CoV-2), is responsible for an ongoing global pandemic. While other countries deployed widespread testing as an early mitigation strategy, the U.S. experienced delays in development and deployment of organism identification assays. As such, there is uncertainty surrounding disease burden and community spread, severely hampering containment efforts. COVID-19 illuminates the need for a tiered diagnostic approach to rapidly identify clinically significant infections and reduce disease spread. Without the ability to efficiently screen patients, hospitals are overwhelmed, potentially delaying treatment for other emergencies. A multi-tiered, diagnostic strategy incorporating a rapid host immune response assay as a screening test, molecular confirmatory testing and rapid IgM/IgG testing to assess benefit from quarantine/further testing and provide information on population exposure/herd immunity would efficiently evaluate potential COVID-19 patients. Triaging patients within minutes with a fingerstick rather than hours/days after an invasive swab is critical to pandemic response as reliance on the existing strategy is limited by assay accuracy, time to results, and testing capacity. Early screening and triage is achievable from the outset of a pandemic with point-of-care host immune response testing which will improve response time to clinical and public health actions.Key messagesDelayed testing deployment has led to uncertainty surrounding overall disease burden and community spread, severely hampering public health containment and healthcare system preparation efforts.A multi-tiered testing strategy incorporating rapid, host immune point-of-care tests can be used now and for future pandemic planning by effectively identifying patients at risk of disease thereby facilitating quarantine earlier in the progression of the outbreak during the weeks and months it can take for pathogen specific confirmatory tests to be developed, validated and manufactured in sufficient quantities.The ability to triage patients at the point of care and support the guidance of medical and therapeutic decisions, for viral isolation or confirmatory testing or for appropriate treatment of COVID-19 and/or bacterial infections, is a critical component to our national pandemic response and there is an urgent need to implement the proposed strategy to combat the current outbreak.

Title: Development and validation of a rapid single-step reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) system potentially to be used for reliable and high-throughput screening of COVID-19 Content: The recent pandemic of COVID-19 has involved tens of thousands of patients in numerous countries and the causative virus, SARS COV-2 is highly transmissible. Molecular diagnostic tools are central to containment of the virus and initiating proper clinical care. Rapidity, user-friendliness, and high degree of sensitivity and specificity are desirable features of diagnostic assays for screening purposes. Herein, we present a single step reverse transcriptase LAMP assay (RT-LAMP), which can detect up to 500 viral copies in 30 minutes. We challenged our assay with a large number of clinical samples collected from 47 confirmed cases and 213 negative patients. Our LAMP assay showed a high degree of sensitivity and specificity compared to two commercialized qRT-PCR assay as gold standard. We present a rapid RT-LAMP assay that could extend the capacity of laboratories to process 2.5 more clinical samples relative to qRT-PCR and potentially could be used for high-throughput screening purposes.

Title: Development of a rapid test kit for SARS-CoV-2: an example of product design Content: We present an example of applying 'need-driven' product design principle to the development of a rapid test kit to detect SARS-COV-2 (COVID-19). The tests are intended for use in the field and, longer term, for home use. They detect whether a subject is currently infected with the virus and is infectious. The urgent need for large numbers of tests in field setting imposes constraints such as short test time and lack of access to specialist equipment, laboratories and skilled technicians to perform the test and interpret results. To meet these needs, an antigen test based on RT-LAMP with colorimetric readout was chosen. Direct use of swab sample with no RNA extraction was explored. After extensive experimental study (reported elsewhere), a rapid test kit has been fabricated to satisfy all design criteria.

Title: Rapid viral diagnosis and ambulatory management of suspected COVID-19 cases presenting at the infectious diseases referral hospital in Marseille, France, - January 31st to March 1st, 2020: A respiratory virus snapshot Content: Abstract Background Rapid virological diagnosis is needed to limit the length of isolation for suspected COVID-19 cases. Method We managed the first 280 patients suspected to have COVID-19 through a rapid care circuit and virological diagnosis in our infectious disease reference hospital in Marseille, France. Rapid viral detection was performed on sputum and nasopharyngeal samples. Results Over our study period, no SARS-CoV-2 was detected. Results were obtained within approximately 3 h of the arrival of patient samples at the laboratory. Other viral infections were identified in 49% of the patients, with most common pathogens being influenza A and B viruses, rhinovirus, metapneumovirus and common coronaviruses, notably HKU1 and NL63. Conclusion Early recognition of COVID-19 is critical to isolate confirmed cases and prevent further transmission. Early rule-out of COVID-19 allows public health containment measures to be adjusted by reducing the time spent in isolation.

Title: Testing For SARS-CoV-2: The Day the World Turned its Attention to the Clinical Laboratory Content: In the last few months, an unprecedented number of laboratory tests for coronavirus disease 2019 (COVID-19) have been developed at a remarkable speed. With the rapid adoption of these tests into clinical practice, combined with the widespread publicity they received, questions arose related to the different types of tests, their utility, performance, and regulatory approval status. The aim of this publication is to provide a general landscape of laboratory testing for COVID-19 and offer a historical and regulatory perspective associated with them. Specifically, we aim to elaborate on the regulatory complexities of diagnostic testing in the United States and its implications to the present outbreak, as well as provide a synopsis of laboratory tests that have been developed for COVID-19. We will first address the detection of severe acute respiratory syndrome-coronavirus 2 directly by either nucleic acid amplification tests or by the detection of the viral protein for active infections. Subsequently, we will provide an overview of serological tests that can aid not only in diagnosis but additionally help to identify prior infections and potential immunity.

Title: Loop mediated isothermal amplification (LAMP) assays as a rapid diagnostic for COVID-19 Content: Recently, a novel coronavirus (SARS-CoV-2; coronavirus disease 2019, COVID-19) has emerged, rapidly spreading and severely straining the capacity of the global health community. Many nations are employing combinations of containment and mitigation strategies, where early diagnosis of COVID-19 is vital in controlling illness progression and limiting viral spread within the population. Thus, rapid and accurate methods of early detection are vital to contain COVID-19 and prevent further spread and predicted subsequent infectious waves of viral recurrence in future. Immediately after its initial characterization, Chinese and American Centers for Disease Control and Prevention (CDCs) rapidly employed molecular assays for detection of COVID-19, mostly employing real-time polymerase chain reaction (RT-PCR) methods. However, such methods require specific expensive items of equipment and highly trained analysts, requiring upwards of 4-8 h to process. These requirements coupled with associated financial pressures may prevent effective deployment of such diagnostic tests. Loop mediated isothermal amplification(LAMP) is method of nucleic acid amplification which exhibits increased sensitivity and specificity are significantly rapid, and do not require expensive reagents or instruments, which aids in cost reduction for coronavirus detection. Studies have shown the successful application of LAMP assays in various forms to detect coronavirus RNA in patient samples, demonstrating that 1-10 copies of viral RNA template per reaction are sufficient for successful detection, ~100-fold more sensitive than conventional RT-PCR methods. Importantly, studies have also now demonstrated the effectiveness of LAMP methodology in the detection of SARS-CoV-2 RNA at significantly low levels, particularly following numerous improvements to LAMP assay protocols. We hypothesise that recent advancements in enhanced LAMP protocols assay perhaps represent the best chance for a rapid and robust assay for field diagnosis of COVID-19, without the requirement of specialized equipment and highly trained professionals to interpret results. Herein, we present our arguments with a view to disseminate such findings, to assist the combat of this virus that is proving so devastating. We hope that this strategy could be applied rapidly, and confirmed for viability with clinical samples, before being rolled out for mass-diagnostic testing in these current times.

Title: A Rapid COVID-19 RT-PCR Detection Assay for Low Resource Settings Content: Quantitative reverse transcription polymerase chain reaction (RT-qPCR) assay is the gold standard recommended to test for acute SARS-CoV-2 infection. It has been used by the Centers for Disease Control and Prevention (CDC) and several other companies in their Emergency Use Authorization (EUA) assays. RT-qPCR requires expensive equipment such as RNA isolation instruments and real-time PCR thermal cyclers, which are not available in many low resource settings and developing countries. As a pandemic, COVID-19 has quickly spread to the rest of the world. Many underdeveloped and developing counties do not have the means for fast and accurate COVID-19 detection to control this outbreak. Using COVID-19 positive clinical specimens, we demonstrated that RT-PCR assays can be performed in as little as 12 minutes using untreated samples, heat-inactivated samples, or extracted RNA templates. Rapid RT-PCR was achieved using thin-walled PCR tubes and a setup including sous vide immersion heaters/circulators. Our data suggest that rapid RT-PCR can be implemented for sensitive and specific molecular diagnosis of COVID-19 in situations where sophisticated laboratory instruments are not available.

Title: A comparison of group testing architectures for COVID-19 testing Content: An important component of every country's COVID-19 response is fast and efficient testing -- to identify and isolate cases, as well as for early detection of local hotspots. For many countries, producing a sufficient number of tests has been a serious limiting factor in their efforts to control COVID-19 infections. Group testing is a well-established mathematical tool, which can provide a serious and rapid improvement to this situation. In this note, we compare several well-established group testing schemes in the context of qPCR testing for COVID-19. We include example calculations, where we indicate which testing architectures yield the greatest efficiency gains in various settings. We find that for identification of individuals with COVID-19, array testing is usually the best choice, while for estimation of COVID-19 prevalence rates in the total population, Gibbs-Gower testing usually provides the most accurate estimates given a fixed and relatively small number of tests. This note is intended as a helpful handbook for labs implementing group testing methods.

Title: Evaluation of the Practicability of a Finger-Stick Whole-Blood SARS-Cov-2 Self-Test Adapted for the General Population. Content: Background COVID-19 (COronaVIrus Disease 2019) is an infectious respiratory disease caused by the novel SARS-CoV-2 virus. Rapid Diagnostic Tests (RDTs) have been developed to detect specific antibodies, IgG and IgM, to SARS-CoV-2 virus in human whole blood and easily usable by the general population are needed in order to alleviate the lockdown that many countries have initiated in response to the growing COVID-19 pandemic. A real-life study has been conducted in order to evaluate the performance of the COVID-PRESTO RDT and the results have been submitted for publication and are currently under review. Even if this test showed very high sensitivity and specificity in a laboratory setting when used by trained professionals, it needs to be further evaluated for practicability when used by common folk in order to be approved by health authorities for in-home use Methods 142 participants were recruited between March 2020 and April 2020 among non-medical populations in central France (nuclear plants workers, individuals attending the Orleans University Hospital vaccination clinic and Orleans University Hospital non-medical staff). Instructions for use with or without a tutorial video was made available to the volunteers. Two separate objectives were pursued: evaluation of the capability of participants to obtain an interpretable result, and evaluation of the users ability to read the results. Results 88.4 % of the test users judged the instruction for use leaflet to be clear and understandable. 99.3 % of the users obtained a valid results and according to the supervisors 92.7% of the tests were properly performed by the user. Overall, 95% of the users gave positive feedback toward the COVID PRESTO as a potential self-test. No influence of age and education was observed. Conclusion COVID-PRESTO was successfully used by an overwhelming majority of participants and its utilization was judged very satisfactory, therefore showing a promising potential as a self-test to be used by the general population. This RDT can become an easy-to-use tool to help know whether individuals are protected or not, particularly in the perspective of a second wave or a mass vaccination program.

Title: Challenges in Laboratory Diagnosis of the Novel Coronavirus SARS-CoV-2 Content: The recent outbreak of the Coronavirus disease 2019 (COVID-19) has quickly spread worldwide since its discovery in Wuhan city, China in December 2019. A comprehensive strategy, including surveillance, diagnostics, research, clinical treatment, and development of vaccines, is urgently needed to win the battle against COVID-19. The past three unprecedented outbreaks of emerging human coronavirus infections at the beginning of the 21st century have highlighted the importance of readily available, accurate, and rapid diagnostic technologies to contain emerging and re-emerging pandemics. Real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) based assays performed on respiratory specimens remain the gold standard for COVID-19 diagnostics. However, point-of-care technologies and serologic immunoassays are rapidly emerging with high sensitivity and specificity as well. Even though excellent techniques are available for the diagnosis of symptomatic patients with COVID-19 in well-equipped laboratories; critical gaps still remain in screening asymptomatic people who are in the incubation phase of the virus, as well as in the accurate determination of live viral shedding during convalescence to inform decisions for ending isolation. This review article aims to discuss the currently available laboratory methods and surveillance technologies available for the detection of COVID-19, their performance characteristics and highlight the gaps in current diagnostic capacity, and finally, propose potential solutions. We also summarize the specifications of the majority of the available commercial kits (PCR, EIA, and POC) for laboratory diagnosis of COVID-19.

Title: Challenges in Laboratory Diagnosis of the Novel Coronavirus SARS-CoV-2. Content: The recent outbreak of the Coronavirus disease 2019 (COVID-19) has quickly spread worldwide since its discovery in Wuhan city, China in December 2019. A comprehensive strategy, including surveillance, diagnostics, research, clinical treatment, and development of vaccines, is urgently needed to win the battle against COVID-19. The past three unprecedented outbreaks of emerging human coronavirus infections at the beginning of the 21st century have highlighted the importance of readily available, accurate, and rapid diagnostic technologies to contain emerging and re-emerging pandemics. Real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) based assays performed on respiratory specimens remain the gold standard for COVID-19 diagnostics. However, point-of-care technologies and serologic immunoassays are rapidly emerging with high sensitivity and specificity as well. Even though excellent techniques are available for the diagnosis of symptomatic patients with COVID-19 in well-equipped laboratories; critical gaps still remain in screening asymptomatic people who are in the incubation phase of the virus, as well as in the accurate determination of live viral shedding during convalescence to inform decisions for ending isolation. This review article aims to discuss the currently available laboratory methods and surveillance technologies available for the detection of COVID-19, their performance characteristics and highlight the gaps in current diagnostic capacity, and finally, propose potential solutions. We also summarize the specifications of the majority of the available commercial kits (PCR, EIA, and POC) for laboratory diagnosis of COVID-19.

Title: Development of a rapid test kit for SARS-CoV-2: an example of product design Content: We present an example of applying ‘need-driven’ product design principle to the development of a rapid test kit to detect SARS-COV-2 (COVID-19). The tests are intended for use in the field and, longer term, for home use. They detect whether a subject is currently infected with the virus and is infectious. The urgent need for large numbers of tests in field setting imposes constraints such as short test time and lack of access to specialist equipment, laboratories and skilled technicians to perform the test and interpret results. To meet these needs, an antigen test based on RT-LAMP with colorimetric readout was chosen. Direct use of swab sample with no RNA extraction was explored. After extensive experimental study (reported elsewhere), a rapid test kit has been fabricated to satisfy all design criteria.

Title: Testing for SARS-CoV-2 (COVID-19): a systematic review and clinical guide to molecular and serological in-vitro diagnostic assays Content: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated Coronavirus disease 2019 (COVID-19) pandemic has demanded rapid upscaling of in-vitro diagnostic assays to enable mass screening and testing of high-risk groups, and simultaneous ascertainment of robust data on past SARS-CoV-2 exposure at an individual and population level. To meet the exponential demand in testing, there has been an accelerated development of both molecular and serological assays across a plethora of platforms. In the present review, we discuss the current literature on these modalities including the nucleic acid amplification tests, direct viral antigen tests and the rapidly expanding laboratory based and point of care serological tests. This suite of complementary tests will inform crucial decisions by healthcare providers and policy makers and understanding their strengths and limitations will be critical to their judicious application for the development of algorithmic approaches to treatment and public health strategies.

Title: Rapid detection of novel coronavirus/Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) by reverse transcription-loop-mediated isothermal amplification Content: Novel Corona virus/Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2 or 2019-nCoV), and the subsequent disease caused by the virus (coronavirus disease 2019 or COVID-19), is an emerging global health concern that requires a rapid diagnostic test. Quantitative reverse transcription PCR (qRT-PCR) is currently the standard for SARS-CoV-2 detection; however, Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP) may allow for faster and cheaper field based testing at point-of-risk. The objective of this study was to develop a rapid screening diagnostic test that could be completed in 30-45 minutes. Simulated patient samples were generated by spiking serum, urine, saliva, oropharyngeal swabs, and nasopharyngeal swabs with a portion of the SARS-CoV-2 nucleic sequence. RNA isolated from nasopharyngeal swabs collected from actual COVID-19 patients was also tested. The samples were tested using RT-LAMP as well as by conventional qRT-PCR. Specificity of the RT-LAMP was evaluated by also testing against other related coronaviruses. RT-LAMP specifically detected SARS-CoV-2 in both simulated patient samples and clinical specimens. This test was performed in 30-45 minutes. This approach could be used for monitoring of exposed individuals or potentially aid with screening efforts in the field and potential ports of entry.

Title: SARS-CoV-2 qRT-PCR Ct value distribution in Japan and possible utility of rapid antigen testing kit Content: The exact pathology of COVID-19 remains mostly unclear, and accurate epidemiological understanding and rapid testing are crucial to overcome this disease. Several types of nucleic acid tests (NAT) have been used in Japan, but information about the viral RNA load, determined by Ct values, of the patients is limited due to the small number of patients tested in each clinical institution and lack of standardization of the testing kits. We have been performing the qRT-PCR tests established by NIID, and the mean Ct value distribution of 62 cases, which are deemed (first-visit) patients, among the total of 88 positive cases tested in a 4-day window of early April, was 24.9 with SD=5.45. Recently approved antigen testing kits were also used in the same samples (62 positives) along with 100 negative cases, and it revealed the positive predictive value of 80.6% and negative predictive value of 100%, with an overall agreement rate of 92.6%. These results indicate that a certain number of patients with lower Ct values, existed in Japan when SARS-CoV-2 virus started to spread. The newly approved rapid antigen testing kit will be a useful tool to identify such populations rapidly.

Title: Diagnostic techniques for COVID-19 and new developments Content: COVID-19 pandemic is a serious global health issue today due to the rapid human to human transmission of SARS-CoV-2, a new type of coronavirus that causes fatal pneumonia. SARS -CoV-2 has a faster rate of transmission than other coronaviruses such as SARS and MERS and until now there are no approved specific drugs or vaccines for treatment. Thus, early diagnosis is crucial to prevent the extensive spread of the disease. The reverse transcription-polymerase chain reaction (RT-PCR) is the most routinely used method until now to detect SARS-CoV-2 infections. However, several other faster and accurate assays are being developed for the diagnosis of COVID-19 aiming to control the spread of infection through the identification of patients and immediate isolation. In this review, we will discuss the various detection methods of the SARS-CoV-2 virus including the recent developments in immunological assays, amplification techniques as well as biosensors.

Title: Rapid detection of novel coronavirus/Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) by reverse transcription-loop-mediated isothermal amplification Content: Novel Corona virus/Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2 or 2019-nCoV), and the subsequent disease caused by the virus (coronavirus disease 2019 or COVID-19), is an emerging global health concern that requires a rapid diagnostic test. Quantitative reverse transcription PCR (qRT-PCR) is currently the standard for SARS-CoV-2 detection; however, Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP) may allow for faster and cheaper field based testing at point-of-risk. The objective of this study was to develop a rapid screening diagnostic test that could be completed in 30–45 minutes. Simulated patient samples were generated by spiking serum, urine, saliva, oropharyngeal swabs, and nasopharyngeal swabs with a portion of the SARS-CoV-2 nucleic sequence. RNA isolated from nasopharyngeal swabs collected from actual COVID-19 patients was also tested. The samples were tested using RT-LAMP as well as by conventional qRT-PCR. Specificity of the RT-LAMP was evaluated by also testing against other related coronaviruses. RT-LAMP specifically detected SARS-CoV-2 in both simulated patient samples and clinical specimens. This test was performed in 30–45 minutes. This approach could be used for monitoring of exposed individuals or potentially aid with screening efforts in the field and potential ports of entry.

Title: Rapid viral diagnosis and ambulatory management of suspected COVID-19 cases presenting at the infectious diseases referral hospital in Marseille, France, - January 31st to March 1st, 2020: A respiratory virus snapshot Content: BACKGROUND: Rapid virological diagnosis is needed to limit the length of isolation for suspected COVID-19 cases. METHOD: We managed the first 280 patients suspected to have COVID-19 through a rapid care circuit and virological diagnosis in our infectious disease reference hospital in Marseille, France. Rapid viral detection was performed on sputum and nasopharyngeal samples. RESULTS: Over our study period, no SARS-CoV-2 was detected. Results were obtained within approximately 3 h of the arrival of patient samples at the laboratory. Other viral infections were identified in 49% of the patients, with most common pathogens being influenza A and B viruses, rhinovirus, metapneumovirus and common coronaviruses, notably HKU1 and NL63. CONCLUSION: Early recognition of COVID-19 is critical to isolate confirmed cases and prevent further transmission. Early rule-out of COVID-19 allows public health containment measures to be adjusted by reducing the time spent in isolation.

Title: Loop mediated isothermal amplification (LAMP) assays as a rapid diagnostic for COVID-19 Content: Abstract Recently, a novel coronavirus (SARS-CoV-2; coronavirus disease 2019, COVID-19) has emerged, rapidly spreading and severely straining the capacity of the global health community. Many nations are employing combinations of containment and mitigation strategies, where early diagnosis of COVID-19 is vital in controlling illness progression and limiting viral spread within the population. Thus, rapid and accurate methods of early detection are vital to contain COVID-19 and prevent further spread and predicted subsequent infectious waves of viral recurrence in future. Immediately after its initial characterization, Chinese and American Centers for Disease Control and Prevention (CDCs) rapidly employed molecular assays for detection of COVID-19, mostly employing real-time polymerase chain reaction (RT-PCR) methods. However, such methods require specific expensive items of equipment and highly trained analysts, requiring upwards of 4-8 hours to process. These requirements coupled with associated financial pressures may prevent effective deployment of such diagnostic tests. Loop mediated isothermal amplification(LAMP) is method of nucleic acid amplification which exhibits increased sensitivity and specificity are significantly rapid, and do not require expensive reagents or instruments, which aids in cost reduction for coronavirus detection. Studies have shown the successful application of LAMP assays in various forms to detect coronavirus RNA in patient samples, demonstrating that 1-10 copies of viral RNA template per reaction are sufficient for successful detection, ∼100-fold more sensitive than conventional RT-PCR methods. Importantly, studies have also now demonstrated the effectiveness of LAMP methodology in the detection of SARS-CoV-2 RNA at significantly low levels, particularly following numerous improvements to LAMP assay protocols. We hypothesise that recent advancements in enhanced LAMP protocols assay perhaps represent the best chance for a rapid and robust assay for field diagnosis of COVID-19, without the requirement of specialized equipment and highly trained professionals to interpret results. Herein, we present our arguments with a view to disseminate such findings, to assist the combat of this virus that is proving so devastating. We hope that this strategy could be applied rapidly, and confirmed for viability with clinical samples, before being rolled out for mass-diagnostic testing in these current times.

Title: Real-time PCR-based SARS-CoV-2 detection in Canadian laboratories Content: With emergence of pandemic COVID-19, rapid and accurate diagnostic testing is essential. This study compared laboratory-developed tests (LDTs) used for the detection of SARS-CoV-2 in Canadian hospital and public health laboratories, and some commercially available real-time RT-PCR assays. Overall, analytical sensitivities were equivalent between LDTs and most commercially available methods.

Title: Real-time PCR-based SARS-CoV-2 detection in Canadian Laboratories Content: With emergence of pandemic COVID-19, rapid and accurate diagnostic testing is essential. This study compared laboratory-developed tests (LDTs) used for the detection of SARS-CoV-2 in Canadian hospital and public health laboratories, and some commercially available real-time RT-PCR assays. Overall, analytical sensitivities were equivalent between LDTs and most commercially available methods.

Title: Laboratory Diagnosis of Coronavirus Disease-2019 (COVID-19) Content: The outbreak of Coronavirus Disease-2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has threatened health worldwide. As of the end of 2020, there were nearly 10 million confirmed cases and nearly 5 million deaths associated with COVID-19. Rapid and early laboratory diagnosis of COVID-19 is the main focus of treatment and control. Molecular tests are the basis for confirmation of COVID-19, but serological tests for SARS-CoV-2 are widely available and play an increasingly important role in understanding the epidemiology of the virus and in identifying populations at higher risk for infection. Point-of-care tests have the advantage of rapid, accurate, portable, low cost and non-specific device requirements, which provide great help for disease diagnosis and detection. This review will discuss the performance of different laboratory diagnostic tests and platforms, as well as suitable clinical samples for testing, and related biosafety protection. This review shall guide for the diagnosis of COVID-19 caused by SARS-CoV-2.

Title: Rapid Implementation of a SARS-CoV-2 Diagnostic qRT-PCR Test with Emergency Use Authorization at a Large Academic Safety-Net Hospital Content: Summary The COVID-19 pandemic is a global public health crisis. Significant delays in the rapid development and distribution of diagnostic testing for SARS-CoV-2 infection have prevented adequate public health management of the disease, impacting the timely mapping of viral spread and the conservation of personal protective equipment. Furthermore, vulnerable populations such as those served by Boston Medical Center (BMC), the largest safety net hospital in New England, represent a high-risk group across multiple dimensions, including a higher prevalence of pre-existing conditions and substance use disorders, lower health maintenance, unstable housing, and a propensity for rapid community spread, highlighting the urgent need for expedient and reliable in-house testing. Here, we report the implementation of a SARS-CoV-2 diagnostic RT-PCR assay with rapid turnaround time enabling more informed decisions with personal and public health ramifications. This work provides a blueprint for academic centers and community hospitals lacking capital-intensive automated laboratory machinery to implement in-house testing.

Title: Laboratory Diagnosis of Coronavirus Disease-2019 (COVID-19) Content: Abstract The outbreak of Coronavirus Disease-2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has threatened health worldwide. As of the end of 2020, there were nearly 10 million confirmed cases and nearly 5 million deaths associated with COVID-19. Rapid and early laboratory diagnosis of COVID-19 is the main focus of treatment and control. Molecular tests are the basis for confirmation of COVID-19, but serological tests for SARS-CoV-2 are widely available and play an increasingly important role in understanding the epidemiology of the virus and in identifying populations at higher risk for infection. Point-of-care tests have the advantage of rapid, accurate, portable, low cost and non-specific device requirements, which provide great help for disease diagnosis and detection. This review will discuss the performance of different laboratory diagnostic tests and platforms, as well as suitable clinical samples for testing, and related biosafety protection. This review shall guide for the diagnosis of COVID-19 caused by SARS-CoV-2.

Title: Scarce COVID-19 Testing Capabilities at Urgent Care Centers in States with Greatest Disease Burden Content: As of March 22, 2020, the number of confirmed COVID-19 cases in the U.S. has reached nearly 30,000. While rapid and accessible diagnosis is paramount to monitoring and reducing the spread of disease, COVID-19 testing capabilities across the U.S. remain constrained. For many individuals, urgent care centers (UCCs) may offer the most accessible avenue to be tested. Through a phone survey, we describe the COVID-19 testing capabilities at UCCs and provide a snapshot highlighting the limited COVID-19 testing capabilities at UCCs in states with the greatest disease burden.

Title: Triaging moderate COVID-19 and other viral pneumonias from routine blood tests Content: The COVID-19 is sweeping the world with deadly consequences. Its contagious nature and clinical similarity to other pneumonias make separating subjects contracted with COVID-19 and non-COVID-19 viral pneumonia a priority and a challenge. However, COVID-19 testing has been greatly limited by the availability and cost of existing methods, even in developed countries like the US. Intrigued by the wide availability of routine blood tests, we propose to leverage them for COVID-19 testing using the power of machine learning. Two proven-robust machine learning model families, random forests (RFs) and support vector machines (SVMs), are employed to tackle the challenge. Trained on blood data from 208 moderate COVID-19 subjects and 86 subjects with non-COVID-19 moderate viral pneumonia, the best result is obtained in an SVM-based classifier with an accuracy of 84%, a sensitivity of 88%, a specificity of 80%, and a precision of 92%. The results are found explainable from both machine learning and medical perspectives. A privacy-protected web portal is set up to help medical personnel in their practice and the trained models are released for developers to further build other applications. We hope our results can help the world fight this pandemic and welcome clinical verification of our approach on larger populations.

Title: Combining Point-of-Care Diagnostics and Internet of Medical Things (IoMT) to Combat the COVID-19 Pandemic Content: The current standard testing method for screening coronavirus disease 2019 (COVID-19) is through reverse real-time PCR assay (rRT-PCR), a common molecular-based assay that requires an average of four to six hours to provide results [...].

Title: Combined point of care nucleic acid and antibody testing for SARS-CoV-2: a prospective cohort study in suspected moderate to severe COVID-19 disease. Content: Abstract Background Rapid COVID-19 diagnosis in hospital is essential for patient management and identification of infectious patients to limit the potential for nosocomial transmission. The diagnosis is complicated by 30-50% of COVID-19 hospital admissions with negative nose/throat swabs negative for SARS-CoV-2 nucleic acid, frequently after the first week of illness when SARS-CoV-2 antibody responses become detectable. We assessed the diagnostic accuracy of combined rapid antibody point of care (POC) and nucleic acid assays for suspected COVID-19 disease in the emergency department. Methods We developed (i) an in vitro neutralization assay using a lentivirus expressing a genome encoding luciferase and pseudotyped with spike protein and (ii) an ELISA test to detect IgG antibodies to nucleocapsid (N) and spike (S) proteins from SARS-CoV-2. We tested two promising candidate lateral flow rapid fingerprick test with bands for IgG and IgM. We then prospectively recruited participants with suspected moderate to severe COVID-19 and tested for SARS-CoV-2 nucleic acid in a combined nasal/throat swab using the standard laboratory RT-PCR and a validated rapid nucleic acid test. Additionally, serum collected at admission was retrospectively tested by in vitro neutralization, ELISA and the candidate POC antibody tests. We determined the sensitivity and specificity of the individual and combined rapid POC diagnostic tests against a composite gold standard of neutralisation and the standard laboratory RT-PCR. Results 45 participants had specimens tested for nucleic acid in nose/throat swabs as well as stored sera for antibodies. Serum neutralisation assay, SARS-CoV-2 Spike IgG ELISA and the POC antibody test results were concordant. Using the composite gold standard, prevalence of COVID-19 disease was 53.3% (24/45). Median age was 73.5 (IQR 54.0-86.5) years in those with COVID-19 disease by our gold standard and 63.0 (IQR 41.0-72.0) years in those without disease. Median duration of symptoms was 7 days (IQR 1-8) in those with infection. The overall sensitivity of rapid NAAT diagnosis was 79.2% (95CI 57.8-92.9%) and 50.0% (11.8-88.2) at days 8-28. Sensitivity and specificity of the combined rapid POC diagnostic tests reached 100% (95CI 85.8-100) and 94.7% (95CI 74.0-99.0) overall. Conclusions Dual point of care SARS-CoV-2 testing can significantly improve diagnostic sensitivity, whilst maintaining high specificity. Rapid combined tests have the potential to transform our management of COVID-19, including inflammatory manifestations where nucleic acid test results are negative. A rapid combined approach will also aid recruitment into clinical trials and in prescribing therapeutics, particularly where potentially harmful immune modulators (including steroids) are used.

Title: COVID-19 Clinical Diagnostics and Testing Technology Content: Given the global nature of the COVID-19 pandemic, the need for disease detection and expanding testing capacity remains a critical priority. This review discusses the technological advances in testing capability and methodology that are currently employed or in development for detecting the novel coronavirus. We describe the current clinical diagnostics and technology, including molecular and serological testing approaches, for SARS-CoV-2 testing as well as address their advantages and limitations. Nucleic acid amplification technology for molecular diagnostics remains the gold standard for virus detection. We highlight alternative molecular detection techniques used for developing novel COVID-19 diagnostics on the horizon. Antibody response against SARS-CoV-2 remains poorly understood and proper validation of serology tests is necessary to demonstrate their accuracy and clinical utility. In order to bring the pandemic under control, we must speed up the development of rapid and widespread testing through improvements in clinical diagnostics and testing technology as well as access to these tools.

Title: Testing for SARS‐CoV‐2: the day the world turned its attention to the clinical laboratory Content: In the last few months, an unprecedented number of laboratory tests for COVID‐19 have been developed at a remarkable speed. With the rapid adoption of these tests into clinical practice, combined with the widespread publicity they received, questions arose related to the different types of tests, their utility, performance, and regulatory approval status. The aim of this publication is to provide a general landscape of laboratory testing for COVID‐19 and offer a historical and regulatory perspective associated with them. Specifically, we aim to elaborate on the regulatory complexities of diagnostic testing in the U.S. and its implications to the present outbreak, as well as provide a synopsis of laboratory tests that have been developed for COVID‐19. We will first address the detection of Sars‐Cov‐2 directly by either nucleic acid amplification tests (NAAT) or by the detection of the viral protein for active infections. Subsequently, we will provide an overview of serological tests that can aid not only in diagnosis but additionally help to identify prior infections and potential immunity.

Title: FAST: a Feasible, Accurate and Speedy Test Strategy for COVID-19 Content: As the COVID-19 pandemic continues worldwide, there is an urgent need to detect infected patients as quickly and accurately as possible. Group testing proposed by Technion [2] could improve efficiency greatly. However, the false negative rate (FNR) would be doubled. Using USA as an example, group testing would have over 70,000 false negatives, compared to 35,000 false negatives by individual testing. In this paper, we propose a Flexible, Accurate and Speedy Test (FAST), which is faster and more accurate than any existing tests. FAST first forms small close contact subgroups, e.g. families and friends. It then pools subgroups to form larger groups before RT-PCR test is done. FAST needs a similar number of tests to Technion's method, but could sharply reduce the FNR to a negligible level. Again taking USA as example, FAST reduces the number of false negatives to just 2000 while it is seven times faster than individual testing.

Title: Ultra-fast one-step RT-PCR protocol for the detection of SARS-CoV-2 Content: The COVID-19 pandemic resulted in lockdowns all over the world thus affecting nearly all aspects of social life and also had a huge impact on global economies. Since vaccines and therapies are still not available for the population, prevention becomes desperately needed. One important aspect for prevention is the identification and subsequent isolation of contagious specimens. The currently used methods for diagnostics are time consuming and also hindered by the limited availability of reagents and reaction costs, thus presenting a bottle neck for prevention of COVID-19 spread. Here, we present a new ultra-fast test method which is ten times faster than conventional diagnostic tests using real time quantitative PCR (RT-qPCR). In addition, this ultra-fast method is easy to handle as well as cost effective. We translated published SARS-CoV-2 testing protocols from the Centers of Disease Control and Prevention (Atlanta, Georgia, USA) and the Charite Berlin (Germany) to the NEXTGENPCR (NGPCR) machine and combined it with a fluorescence-based endpoint measurement. Fluorescence was measured with a commercial blue light scanner. We confirmed the NEXTGENPCR results with commercially available positive controls. In addition, we isolated RNA from SARS-CoV-2 infected patients and achieved similar results to clinical RT-qPCR assays. Here, we could show correlation between the results obtained by NEXTGENPCR and conventional RT-qPCR.

Title: Evaluation of performance of two SARS-CoV-2 Rapid whole-blood finger-stick IgM-IgGCombined Antibody Tests Content: Background The SARS-CoV-2 virus is responsible for the infectious respiratory disease called COVID-19 (COronaVIrus Disease). In response to the growing COVID-19 pandemic, Rapid Diagnostic Tests (RDTs) have been developed to detect specific antibodies, IgG and IgM, to SARS-CoV-2 virus in human whole blood. We conducted a real-life study to evaluate the performance of two RDTs, COVID-PRESTO and COVID-DUO, compared to the gold standard, RT-PCR. Methods RT-PCR testing of SARS-Cov-2 was performed from nasopharyngeal swab specimens collected in adult patients visiting the infectious disease department at the hospital (Orleans, France). Fingertip whole blood samples taken at different time points after onset of the disease were tested with RDTs. The specificity and sensitivity of the rapid test kits compared to test of reference (RT-PCR) were calculated. Results Among 381 patients with symptoms of COVID-19 who went to the hospital for a diagnostic, 143 patients were RT-PCR negative. Results of test with RDTs were all negative for these patients, indicating a specificity of 100% for both RDTs. In the RT-PCR positive subgroup (n=238), 133 patients were tested with COVID-PRESTO and 129 patients were tested with COVID-DUO (24 patients tested with both). The further the onset of symptoms was from the date of collection, the greater the sensitivity. The sensitivity of COVID-PRESTO test ranged from 10.00% for patients having experienced their 1st symptoms from 0 to 5 days ago to 100% in patients where symptoms had occurred more than 15 days before the date of tests. For COVID-DUO test, the sensitivity ranged from 35.71% [0-5 days] to 100% (> 15 days). Conclusion COVID-PRESTO and DUO RDTs turned out to be very specific (none false positive) and to be sensitive enough after 15 days from onset of symptom. These easy to use IgG/IgM combined test kits are the first ones allowing a screening with capillary blood sample, by typing from a finger prick. These rapid tests are particularly interesting for screening in low resource settings.

Title: The Royal College of Pathologists of Australasia (RCPA) position statement on COVID-19 Content: For the detection of early COVID-19 disease, RCPA supports the use of molecular tests for SARS-CoV-2 and strongly opposes the introduction of COVID-19 IgG/IgM rapid tests for this purpose.

Title: The Royal College of Pathologists of Australasia (RCPA) position statement on COVID-19. Content: For the detection of early COVID-19 disease, RCPA supports the use of molecular tests for SARS-CoV-2 and strongly opposes the introduction of COVID-19 IgG/IgM rapid tests for this purpose.

Title: CONTAIN: An open-source shipping container laboratory optimised for automated COVID-19 diagnostics Content: The COVID-19 pandemic has challenged diagnostic systems globally. Expanding testing capabilities to conduct population-wide screening for COVID-19 requires innovation in diagnostic services at both the molecular and industrial scale. No report to-date has considered the complexity of laboratory infrastructure in conjunction with the available molecular assays to offer a standardised solution to testing. Here we present CONTAIN. A modular biosafety level 2+ laboratory optimised for automated RT-qPCR COVID-19 testing based on a standard 40ft shipping container. Using open-source liquid-handling robots and RNA extraction reagents we demonstrate a reproducible workflow for RT-qPCR COVID-19 testing. With five OT2 liquid handlers, a single CONTAIN unit reaches a maximum daily testing capacity of 2400 tests/day. We validate this workflow for automated RT-qPCR testing, using both synthetic SARS-CoV-2 samples and patient samples from a local NHS hospital. Finally, we discuss the suitability of CONTAIN and its flexibility in a range of diagnostic testing scenarios including high-density urban environments and mobile response units. Visual abstract

Title: Rapid development of COVID-19 rapid diagnostics for low resource settings: accelerating delivery through transparency, responsiveness, and open collaboration Content: In January, Mologic, embarked on a product development pathway for COVID-19 diagnostics focusing on ELISA and rapid diagnostic tests (RDTs), with anticipated funding from Wellcome Trust and DFID. 755 clinical samples from known COVID-19 patients and hospital negative controls were tested on Mologics IgG ELISA. The reported sensitivity on 191 SGUL prospectively enrolled patients was 95% on day 7 or more post diagnosis, and 97% 10 days or more post-diagnosis. A specificity panel comprising 564 samples pre-December 2019 were tested to include most common respiratory pathogens, other types of coronavirus, and flaviviruses. Specificity in this panel was 97%. This is the first in a series of Mologic products for COVID-19, which will be deployed for COVID-19 diagnosis, contact tracing and sero-epidemiological studies to estimate disease burden and transmission with a focus on ensuring access, affordability, and availability to lowest resource settings.

Title: COVID-19 diagnostics in context Content: The coronavirus disease 2019 (COVID-19) pandemic has highlighted the need for different types of diagnostics, comparative validation of new tests, faster approval by federal agencies, and rapid production of test kits to meet global demands. In this Perspective, we discuss the utility and challenges of current diagnostics for COVID-19.

Title: COVID-19 diagnostics in context. Content: The coronavirus disease 2019 (COVID-19) pandemic has highlighted the need for different types of diagnostics, comparative validation of new tests, faster approval by federal agencies, and rapid production of test kits to meet global demands. In this Perspective, we discuss the utility and challenges of current diagnostics for COVID-19.

Title: A deep dive into testing and management of COVID-19 for Australian high performance and professional sport Content: The purpose of testing for any communicable disease is to support clinicians in the diagnosis and management of individual patients and to describe transmission dynamics. The novel coronavirus is formally named SARS-CoV-2 and the clinical disease state resulting from an infection is known as COVID-19. Control of the COVID-19 pandemic requires clinicians, epidemiologists, and public health officials to utilise the most comprehensive, accurate and timely information available to manage the rapidly evolving COVID-19 environment. High performance sport is a unique context that may look towards comprehensive testing as a means of risk mitigation. Characteristics of the common testing options are discussed including the circumstances where additional testing may be of benefit and considerations for the associated risks. Finally, a review of the available technology that could be considered for use by medical staff at the point of care (PoC) in a high-performance sporting context is included.

Title: COVID-19 paraclinical diagnostic tools: Updates and future trends Content: MOTIVATION: COVID-19 is one of the most widely affecting pandemics. As for many respiratory viruses-caused diseases, diagnosis of COVID-19 relies on two main compartments: clinical and paraclinical diagnostic criteria. Rapid and accurate diagnosis is vital in such a pandemic. On one side, rapidity may enhance management effectiveness, while on the other, coupling efficiency and less costly procedures may permit more effective community-scale management. METHODOLOGY AND MAIN STRUCTURE: In this review, we shed light on the most used and the most validated diagnostic tools. Furthermore, we intend to include few under-development techniques that may be potentially useful in this context. The practical intent of our work is to provide clinicians with a realistic summarized review of the essential elements in the applied paraclinical diagnosis of COVID-19.

Title: A deep dive into testing and management of COVID-19 for Australian high performance and professional sport Content: Abstract The purpose of testing for any communicable disease is to support clinicians in the diagnosis and management of individual patients and to describe transmission dynamics. The novel coronavirus is formally named SARS-CoV-2 and the clinical disease state resulting from an infection is known as COVID-19. Control of the COVID-19 pandemic requires clinicians, epidemiologists, and public health officials to utilise the most comprehensive, accurate and timely information available to manage the rapidly evolving COVID-19 environment. High performance sport is a unique context that may look towards comprehensive testing as a means of risk mitigation. Characteristics of the common testing options are discussed including the circumstances where additional testing may be of benefit and considerations for the associated risks. Finally, a review of the available technology that could be considered for use by medical staff at the point of care (PoC) in a high-performance sporting context is included.

Title: Assay Techniques and Test Development for COVID-19 Diagnosis Content: An ongoing theme of the COVID-19 pandemic is the need for widespread availability of accurate and eﬃcient diagnostic testing for detection of SARS-CoV-2 and antiviral antibodies in infected individuals. This report describes various assay techniques and tests for COVID-19 diagnosis. Most tests for early detection of SARS-CoV-2 RNA rely on the reverse transcription-polymerase chain reaction, but isothermal nucleic acid ampliﬁcation assays, including transcription-mediated ampliﬁcation and CRISPR-based methodologies, are promising alternatives. Identiﬁcation of individuals who have developed antibodies to the SARS-CoV-2 virus requires serological tests, including enzyme-linked immunosorbent assay (ELISA) and lateral ﬂow immunoassay. This report also provides an overview of current development in COVID-19 diagnostic techniques and products to facilitate future improvement and innovation.

Title: Analytical Validation of a COVID-19 qRT-PCR Detection Assay Using a 384-well Format and Three Extraction Methods Content: The COVID-19 global pandemic is an unprecedented health emergency. Insufficient access to testing has hampered effective public health interventions and patient care management in a number of countries. Furthermore, the availability of regulatory-cleared reagents has challenged widespread implementation of testing. We rapidly developed a qRT-PCR SARS-CoV-2 detection assay using a 384-well format and tested its analytic performance across multiple nucleic acid extraction kits. Our data shows robust analytic accuracy on residual clinical biospecimens. Limit of detection sensitivity and specificity was confirmed with currently available commercial reagents. Our methods and results provide valuable information for other high-complexity laboratories seeking to develop effective, local, laboratory-developed procedures with high-throughput capability to detect SARS-CoV-2.

Title: Diagnostic tests for SARS-CoV-2: Implications in head and neck oncology Content: • Screening is imperative to safeguard patients, practitioners and staff. • Various tests available for screening and diagnosing patients for SARS-CoV-2. • Rapid test can be used to screen patients before any surgical intervention. • Along with testing, clinical features should be corroborated. • Oral findings might aid in early diagnosis of COVID-19.

Title: Navigating the Pandemic Response Life Cycle: Molecular Diagnostics and Immunoassays in the Context of COVID-19 Management Content: Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To counter COVID-19 spreading, an infrastructure to provide rapid and thorough molecular diagnostics and serology testing is the cornerstone of outbreak and pandemic management. We hereby review the clinical insights with regard to using molecular tests and immunoassays in the context of COVID-19 management life cycle: the preventive phase, the preparedness phase, the response phase and the recovery phase. The spatial and temporal distribution of viral RNA, antigens and antibodies during human infection is summarized to provide a biological foundation for accurate detection of the disease. We shared the lessons learned and the obstacles encountered during real world high-volume screening programs. Clinical needs are discussed to identify existing technology gaps in these tests. Leverage technologies, such as engineered polymerases, isothermal amplification, and direct amplification from complex matrices may improve the productivity of current infrastructure, while emerging technologies like CRISPR diagnostics, visual end point detection, and PCR free methods for nucleic acid sensing may lead to at-home tests. The lessons learned, and innovations spurred from the COVID-19 pandemic could upgrade our global public health infrastructure to better combat potential outbreaks in the future.

Title: Navigating the Pandemic Response Life Cycle: Molecular Diagnostics and Immunoassays in the Context of COVID-19 Management. Content: Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To counter COVID-19 spreading, an infrastructure to provide rapid and thorough molecular diagnostics and serology testing is the cornerstone of outbreak and pandemic management. We hereby review the clinical insights with regard to using molecular tests and immunoassays in the context of COVID-19 management life cycle: the preventive phase, the preparedness phase, the response phase and the recovery phase. The spatial and temporal distribution of viral RNA, antigens and antibodies during human infection is summarized to provide a biological foundation for accurate detection of the disease. We shared the lessons learned and the obstacles encountered during real world high-volume screening programs. Clinical needs are discussed to identify existing technology gaps in these tests. Leverage technologies, such as engineered polymerases, isothermal amplification, and direct amplification from complex matrices may improve the productivity of current infrastructure, while emerging technologies like CRISPR diagnostics, visual end point detection, and PCR free methods for nucleic acid sensing may lead to at-home tests. The lessons learned, and innovations spurred from the COVID-19 pandemic could upgrade our global public health infrastructure to better combat potential outbreaks in the future.

Title: Development Optimization and Validation of RT-LAMP based COVID-19 Facility in Pakistan Content: The pandemic SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2) has created a widespread panic across the globe especially in the developing countries like Pakistan. The lack of resources and technical staff are causing havoc challenges in the detection and prevention of this global outbreak. Therefore, a less expensive and massive screening of suspected individuals for COVID-19 is required. In this study, a user-friendly technique of reverse transcription-loop mediated isothermal amplification (RT-LAMP) was designed and validated to suggest a potential RT-qPCR alternate for rapid testing of COVID-19 suspected individuals. A total of 12 COVID-19 negative and 72 COVID-19 suspected individuals were analyzed. Both RT-qPCR and RT-LAMP assays were performed for all the individuals using open reading frame (ORF 1ab), nucleoprotein (N) and Spike (S) genes. All 12 specimens which were negative using RT-qPCR were also found negative using RT-LAMP assay. Overall 62 out of 72 positive samples (detected using RT-qPCR) were found COVID-19 positive using RT-LAMP assay. Interestingly all samples (45) having Ct values less than 30 showed 100% sensitivity. However, samples with weaker Ct values (i.e., => 35) showed 54% concordance, suggesting potential false negatives or false positives in RT-LAMP or RT-qPCR results, respectively. Overall comparative assessment showed that RT-LAMP assay showed strong sensitivity and specificity and can be used as an alternative strategy for rapid COVID-19 testing. Hence, based on fast processing time, minimal risk of specimens transfer and utilizing available resources, LAMP based detection of COVID-19 is strongly advocated especially for developing countries.

Title: Four point-of-care lateral flow immunoassays for diagnosis of COVID-19 and for assessing dynamics of antibody responses to SARS-CoV-2 Content: OBJECTIVES: We aimed to evaluate the role of rapid serological tests in the management of coronavirus disease 2019 (COVID-19) patients. METHODS: This retrospective study enrolled 16 real-time reverse transcription polymerase chain reaction-confirmed symptomatic patients with COVID-19 and 58 COVID-19 negative patients at a medical center in Taiwan over a 3-month period. Serial serum samples were collected and tested for antibody response using four point-of-care (POC) lateral flow immunoassays (LFIA) (ALLTEST 2019-nCoV IgG/IgM Rapid Test, Dynamiker 2019-nCoV IgG/IgM Rapid Test, ASK COVID-19 IgG/IgM Rapid Test, and Wondfo SARS-CoV-2 Antibody Test). Time-dependent detection sensitivity and timeliness of seroconversion were determined and compared between the four POC rapid tests. RESULTS: The overall sensitivity and specificity of the four tests for detecting anti-SARS-CoV-2 antibodies after 3 weeks of symptom onset were 100% and 100%, respectively. There was no significant difference between the rapid tests used for detection of IgM and IgG separately and those used for detection of combined total antibody (mainly IgM/IgG). There was no significant difference between the four POC rapid tests in terms of time required for determining seroconversion of COVID-19. Patients with COVID-19 with pneumonia demonstrated shorter seroconversion time than those without pneumonia. CONCLUSION: Though the POC antibody rapid tests based on LFIA showed reliable performance in the detection of SARS-CoV-2-specific antibodies, the results of these tests should be interpreted and applied appropriately in the context of antibody dynamic of COVID-19 infection. COVID-19 patients complicated with pneumonia exhibited earlier anti-SARS-CoV-2 antibody response than COVID-19 patients without pneumonia.

Title: COVID‐19 Clinical Diagnostics and Testing Technology Content: Given the global nature of the COVID‐19 pandemic, the need for disease detection and expanding testing capacity remains a critical priority. This review discusses the technological advances in testing capability and methodology that are currently employed or in development for detecting the novel coronavirus. We describe the current clinical diagnostics and technology, including molecular and serological testing approaches, for SARS‐CoV‐2 testing as well as address their advantages and limitations. Nucleic acid amplification technology for molecular diagnostics remains the gold standard for virus detection. We highlight alternative molecular detection techniques used for developing novel COVID‐19 diagnostics on the horizon. Antibody response against SARS‐CoV‐2 remains poorly understood and proper validation of serology tests is necessary to demonstrate their accuracy and clinical utility. In order to bring the pandemic under control, we must speed up the development of rapid and widespread testing through improvements in clinical diagnostics and testing technology as well as access to these tools.

Title: Evaluating the adequacy of Prima Covid-19 IgG/IgM Rapid Test for the assessment of exposure to SARS-CoV-2 virus Content: The outbreak of the SARS-CoV-2 in early 2020 found health authorities worldwide unprepared to control the pandemic. The adoption of accurate, rapid and inexpensive methods to identify infected subjects in the general population is of paramount relevance for the control of the disease. We evaluated one of the available serological tests, the Prima Lab Covid-19 IgG/IgM Rapid Tests, on 739 volunteers. We first assessed the test's reproducibility by administering it twice on the same day on 104 subjects obtaining and overall score of 93 percent. Since the intensity of the color in the test line regions varies depending on the concentration of Covid-19 antibodies in each sample and that the determination of the positivity depends strictly on the subjective assessment by the reader, after excluding the subjects whose color intensity was too tenuous to be deemed unquestionably positive by the reader the reproducibility increased to 96%. The test would not perform properly for 6 subjects for a very limited overall technical failure of 0.83%. For 138 subjects information was available regarding a previous Real Time PCR nasopharyngeal swab test performed elsewhere. The correspondence of positive results between the two tests was 90.58% (125/138). In spite of some limitation owing especially to the choice of a self selected population sample, we conclude that Prima Lab Covid-19 IgG/IgM Rapid Test represents a low-cost, easily applicable and reproducible tool in detecting SARS-Cov-2 diffusion in the general population.

Title: Immunochromatographic test for the detection of SARS-CoV-2 in saliva Content: We evaluated the rapid immunochromatographic test for SARS-CoV-2 antigen detection using 16 saliva specimens collected from 6 COVID-19 hospitalized patients, and detected N-antigen in 4 of 7 RT-PCR positive specimens. The POCT antigen test using saliva is highly considered to be a game-changer for COVID-19 diagnosis.

Title: Poolkeh Finds the Optimal Pooling Strategy for a Population-wide COVID-19 Testing (Israel, UK, and US as Test Cases) Content: The SARS-CoV-2 pandemic has changed the lifestyle of citizens of the world. In order for decision makers to manage the viral spread of COVID-19 both in the intra-national and the international frontiers, it is essential to operate based on data-driven assessments. It's crucial to do so rapidly and frequently, since the nature of the viral spread grows exponentially and can burst worldwide again. A fast and accurate health status of individuals globally during a pandemic can save many lives and bring life back to a new normal. Herein, we present a data-driven tool to allow decision-makers to assess the spread of the virus among the world population. Our framework allows health agencies to maximize the throughput of COVID-19 tests among the world population by finding the best test pooling that fits the current SIR-D status of the nation.

Title: Molecular and Serological Tests for COVID-19. A Comparative Review of SARS-CoV-2 Coronavirus Laboratory and Point-of-Care Diagnostics Content: Validated and accurate laboratory testing for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a crucial part of the timely management of Coronavirus Disease 2019 (COVID-19) disease, supporting the clinical decision-making process for infection control at the healthcare level and detecting asymptomatic cases. This would facilitate an appropriate treatment, a prompt isolation and consequently deceleration of the pandemic. Various laboratory tests can identify the genetic material of SARS-CoV-2 that causes COVID-19 in specimens, or specific anti-viral antibodies in blood/serum. Due to the current pandemic situation, a development of point-of-care diagnostics (POCD) allows us to substantially accelerate taking clinical decisions and implement strategic planning at the national level of preventative measures. This review summarizes and compares the available POCD and those currently under development, including quantitative reverse transcription PCR (RT-qPCR), serology immunoassays (SIAs) and protein microarray method (PMM) designed for standard and rapid COVID-19 diagnosis.

Title: COVID 19 diagnostic multiplicity and its role in community surveillance and control. Content: Diagnosis of persons exposed to/infected with severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) is central to controlling the global pandemic of COVID-19. Currently, several diagnostic modalities are available for COVID-19, each with its own pros and cons. Although there is a global consensus to increase the testing capacity, it is also essential to prudently utilize these tests to control the pandemic. In this paper, we have reviewed the current array of diagnostics for SARS-CoV-2, highlighted the gaps in current diagnostic modalities, and their role in community surveillance and control of the pandemic. The different modalities of COVID-19 diagnosis discussed are: clinical and radiological, molecular based (laboratory based and point-of-care), Immunoassay based (ELISA, rapid antigen and antibody detection tests) and digital diagnostics (artificial intelligence based algorithms). The role of rapid antigen/antibody detection tests in community surveillance has also been described here. These tests can be used to identify asymptomatic persons exposed to the virus and in community based seroprevalence surveys to assess the epidemiology of spread of the virus. However, there are few concerns about the accuracy of these tests which needs to evaluated beforehand.

Title: Severe underestimation of COVID-19 case numbers: effect of epidemic growth rate and test restrictions Content: To understand the scope and development of the COVID-19 pandemic, knowledge of the number of infected persons is essential. Often, the number of "confirmed cases", which is based on positive RT-PCR test results, is regarded as a reasonable indicator. However, limited COVID-19 test capacities in many countries are restricting the amount of testing that can be done. This can lead to the implementation of testing policies that restrict access to COVID-19 tests, and to testing backlogs and delays. As a result, confirmed case numbers can be significantly lower than the actual number of infections, especially during rapid growth phases of the epidemic. This study examines the quantitative relation between infections and reported confirmed case numbers for two different testing strategies, "limited" and "inclusive" testing, in relation to the growth rate of the epidemic. The results indicate that confirmed case numbers understate the actual number of infections substantially; during rapid growth phases where the daily growth rate can reach or exceed 30%, as has been seen in many countries, the confirmed case numbers under-report actual infections by up to 50 to 100-fold.

Title: Low-Cost and High-Throughput Testing of COVID-19 Viruses and Antibodies via Compressed Sensing: System Concepts and Computational Experiments Content: Coronavirus disease 2019 (COVID-19) is an ongoing pandemic infectious disease outbreak that has significantly harmed and threatened the health and lives of millions or even billions of people. COVID-19 has also negatively impacted the social and economic activities of many countries significantly. With no approved vaccine available at this moment, extensive testing of COVID-19 viruses in people are essential for disease diagnosis, virus spread confinement, contact tracing, and determining right conditions for people to return to normal economic activities. Identifying people who have antibodies for COVID-19 can also help select persons who are suitable for undertaking certain essential activities or returning to workforce. However, the throughputs of current testing technologies for COVID-19 viruses and antibodies are often quite limited, which are not sufficient for dealing with COVID-19 viruses' anticipated fast oscillating waves of spread affecting a significant portion of the earth's population. In this paper, we propose to use compressed sensing (group testing can be seen as a special case of compressed sensing when it is applied to COVID-19 detection) to achieve high-throughput rapid testing of COVID-19 viruses and antibodies, which can potentially provide tens or even more folds of speedup compared with current testing technologies. The proposed compressed sensing system for high-throughput testing can utilize expander graph based compressed sensing matrices developed by us \cite{Weiyuexpander2007}.

Title: Laboratory Testing Methods for Novel Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) Content: Following the first reports of coronavirus disease-19 (COVID-19) by China to the World Health Organization (WHO) on 31st December 2019, more than 4,302,774 novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) cases have been reported by authorities in 212 countries and territories by 12th May 2020. The outbreak and spread of COVID-19 worldwide, highlights the critical need for developing rapid and accurate diagnostic testing methods for emerging human coronavirus (CoV) infections. Testing is crucial to track the spread of disease during a pandemic, and to swiftly permit public health interventions including isolation, quarantine, and appropriate clinical management of afflicted individuals. The key components of viral diagnostic tests are (1) collection of the appropriate sample (blood, nasal swab, and throat swab), (2) availability of the genetic and proteomic sequences of the novel virus for analysis, and (3) rapid and accurate laboratory testing methods. The current gold standard for the molecular diagnosis of SARS-CoV-2 infection is the real-time reverse transcriptase-polymerase chain reaction (RT-PCR) for the qualitative and quantitative detection of viral nucleic acids. Other relevant laboratory methods include enzyme-linked immunoassays (EIA) for viral antibody and antigen detection, and serum viral neutralization (SVN) assays for antibody neutralization determination. The challenges faced in developing a diagnostic test for a novel pathogen are the ability to measure low viral loads for early detection, to provide low or no cross-reactivity with other viral strains and to deliver results rapidly. Several point-of-care molecular devices are currently being integrated for fast and accurate diagnosis of SARS-CoV-2 infections. This review discusses the current laboratory methods available to test for coronaviruses by focusing on the present COVID-19 outbreak.

Title: Types of Assays for SARS-CoV-2 Testing: A Review Content: Clinical laboratory testing routinely provides actionable results, which help direct patient care in the inpatient and outpatient settings. Since December 2019, a novel coronavirus (SARS-CoV-2) has been causing disease (COVID-19 [coronavirus disease 2019]) in patients, beginning in China and now extending worldwide. In this context of a novel viral pandemic, clinical laboratories have developed multiple novel assays for SARS-CoV-2 diagnosis and for managing patients afflicted with this illness. These include molecular and serologic-based tests, some with point-of-care testing capabilities. Herein, we present an overview of the types of testing available for managing patients with COVID-19, as well as for screening of potential plasma donors who have recovered from COVID-19.

Title: Types of Assays for SARS-CoV-2 Testing: A Review. Content: Clinical laboratory testing routinely provides actionable results, which help direct patient care in the inpatient and outpatient settings. Since December 2019, a novel coronavirus (SARS-CoV-2) has been causing disease (COVID-19 [coronavirus disease 2019]) in patients, beginning in China and now extending worldwide. In this context of a novel viral pandemic, clinical laboratories have developed multiple novel assays for SARS-CoV-2 diagnosis and for managing patients afflicted with this illness. These include molecular and serologic-based tests, some with point-of-care testing capabilities. Herein, we present an overview of the types of testing available for managing patients with COVID-19, as well as for screening of potential plasma donors who have recovered from COVID-19.

Title: COVID 19 diagnostic multiplicity and its role in community surveillance and control Content: Diagnosis of persons exposed to/infected with severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) is central to controlling the global pandemic of COVID-19 Currently, several diagnostic modalities are available for COVID-19, each with its own pros and cons Although there is a global consensus to increase the testing capacity, it is also essential to prudently utilize these tests to control the pandemic In this paper, we have reviewed the current array of diagnostics for SARS-CoV-2, highlighted the gaps in current diagnostic modalities, and their role in community surveillance and control of the pandemic The different modalities of COVID-19 diagnosis discussed are: clinical and radiological, molecular based (laboratory based and point-of-care), Immunoassay based (ELISA, rapid antigen and antibody detection tests) and digital diagnostics (artificial intelligence based algorithms) The role of rapid antigen/antibody detection tests in community surveillance has also been described here These tests can be used to identify asymptomatic persons exposed to the virus and in community based seroprevalence surveys to assess the epidemiology of spread of the virus However, there are few concerns about the accuracy of these tests which needs to evaluated beforehand

Title: A mathematical study on the spread of COVID-19 considering social distancing and rapid assessment : The case of Jakarta, Indonesia Content: The aim of this study is to investigate the effects of rapid testing and social distancing in controlling the spread of COVID-19, particularly in the city of Jakarta, Indonesia. We formulate a modified susceptible exposed infectious recovered compartmental model considering asymptomatic individuals. Rapid testing is intended to trace the existence of asymptomatic infected individuals among the population. This asymptomatic class is categorized into two subclasses: detected and undetected asymptomatic individuals. Furthermore, the model considers the limitations of medical resources to treat an infected individual in a hospital. The model shows two types of equilibrium point: COVID-19 free and COVID-19 endemic. The COVID-19-free equilibrium point is locally and asymptotically stable if the basic reproduction number [Formula: see text] is less than unity. In contrast, COVID-19-endemic equilibrium always exists when [Formula: see text]. The model can also show a backward bifurcation at [Formula: see text] whenever the treatment saturation parameter, which describes the hospital capacity, is larger than a specific threshold. To justify the model parameters, we use the incidence data from the city of Jakarta, Indonesia. The data pertain to infected individuals who self-isolate in their homes and visit the hospital for further treatment. Our numerical experiments indicate that strict social distancing has the potential to succeed in reducing and delaying the time of an outbreak. However, if the strict social distancing policy is relaxed, a massive rapid-test intervention should be conducted to avoid a large-scale outbreak in the future.

Title: Clinical evaluation of self-collected saliva by RT-qPCR, direct RT-qPCR, RT-LAMP, and a rapid antigen test to diagnose COVID-19 Content: Background The clinical performance of six molecular diagnostic tests and a rapid antigen test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were clinically evaluated for the diagnosis of coronavirus disease 2019 (COVID-19) in self-collected saliva. Methods Saliva samples from 103 patients with laboratory-confirmed COVID-19 (15 asymptomatic and 88 symptomatic) were collected on the day of hospital admission. SARS-CoV-2 RNA in saliva was detected using a quantitative reverse-transcription polymerase chain reaction (RT-qPCR) laboratory-developed test (LDT), a cobas SARS-CoV-2 high-throughput system, three direct RT-qPCR kits, and reverse-transcription loop mediated isothermal amplification (RT-LAMP). Viral antigen was detected by a rapid antigen immunochromatographic assay. Results Of the 103 samples, viral RNA was detected in 50.5-81.6% of the specimens by molecular diagnostic tests and an antigen was detected in 11.7% of the specimens by the rapid antigen test. Viral RNA was detected at a significantly higher percentage (65.6-93.4%) in specimens collected within 9 d of symptom onset compared to that of specimens collected after at least 10 d of symptom onset (22.2-66.7%) and that of asymptomatic patients (40.0-66.7%). Viral RNA was more frequently detected in saliva from males than females. Conclusions Self-collected saliva is an alternative specimen diagnosing COVID-19. LDT RT-qPCR, cobas SARS-CoV-2 high-throughput system, direct RT-qPCR except for one commercial kit, and RT-LAMP showed sufficient sensitivity in clinical use to be selectively used according to clinical settings and facilities. The rapid antigen test alone is not recommended for initial COVID-19 diagnosis because of its low sensitivity.

Title: The role of testing in infectious disease control: A case of COVID-19 in Africa Content: The dramatic increase in COVID-19 suspected cases in Africa has placed enormous burden on public and private clinical facilities. Till date, the most commonly used method for the identification and confirmation of the virus is the laboratory-based reverse transcription-polymerase chain reaction (RT-PCR) testing. Unfortunately, testing capacities have been limited in many parts of Africa because of inadequate test kits which have restricted scaling up beyond the few public health laboratories at designated locations. We present in this mini-review Africa's preparedness and readiness toward testing, why testing is crucial, the need to immediately strengthen existing facilities and what it involves as combined approaches for managing the COVID-19 crisis. The review highlights the urgent need for speedy expansion and distribution of several laboratory testing platforms to public health facilities and fully accredited private clinical laboratories, including real-time PCR and serological assays.

Title: On Accelerated Testing for COVID-19 Using Group Testing Content: COVID-19 has resulted in a global health crisis that may become even more acute over the upcoming months. One of the main reasons behind the current rapid growth of COVID-19 in the U.S. population is the limited availability of testing kits and the relatively-high cost of screening tests. In this draft, we demonstrate the effectiveness of group testing (pooling) ideas to accelerate testing for COVID-19. This draft is semi-tutorial in nature and is written for a broad audience with interest in mathematical formulations relevant to COVID-19 testing. Therefore, ideas are presented through illustrative examples rather than through purely theoretical formulations. The focus is also on pools of size less than 64 such as what is practical with current RT-PCR technology.

Title: Prevalence of IgG and IgM antibodies to SARS-CoV-2 among clinic staff and patients Content: The coronavirus disease 2019 (COVID-19) is now a pandemic with devastating social and economic consequences. The extent of the spread of COVID-19 within populations is uncertain since diagnostic tests have not been carried out on all eligible persons and doing such diagnostic tests on everyone is much less feasible in developing countries such as Nigeria. Tests for antibodies to SARS-CoV-2, the virus that causes COVID-19, are more affordable, readily available, and require minimal training than current diagnostic tests. Employing a seroepidemiological strategy, serological tests were conducted on 66 volunteering staff and patients at the University of Calabar Teaching Hospital (UCTH), a Federal Government owned tertiary healthcare facility, to determine the extent of exposure to SARS-CoV-2, from 17th to 25th June 2020. Using a COVID-19 IgG/IgM Rapid Test Cassette with emergency use authorization (EUA) from the Food and Drug Administration (FDA) of the United States, it was observed that of the 66 samples tested, 5 (7.6%) were both IgG and IgM positive and 17 (26%) were IgG positive. Moreover, for 44 of the 66 participants, simultaneous tests were carried out using a rapid test kit from a different manufacturer but without FDA-EUA and all the results completely matched with the FDA-EUA kit, except one case where the FDA-EUA kit showed positive for both IgG and IgM while the other kit was positive only for IgM. The 26% positive IgG indicates a high exposure rate for the hospital staff and patients and points to community transmission where the facility is situated. Hence, immediate activation of WHO guidelines for controlling community transmission is called for. These results can further serve as a pilot study to guide public health policies in response to COVID-19 pandemic in both the general population and in healthcare settings.

Title: Fighting COVID-19: Integrated Micro- and Nanosystems for Viral Infection Diagnostics Content: The pandemic of coronavirus disease 2019 (COVID-19) highlights the importance of rapid and sensitive diagnostics of viral infection that enables the efficient tracing of cases and the implementation of public health measures for disease containment. The immediate actions from both academia and industry have led to the development of many COVID-19 diagnostic systems that have secured fast-track regulatory approvals and have been serving our healthcare frontlines since the early stage of the pandemic. On diagnostic technologies, many of these clinically validated systems have significantly benefited from the recent advances in micro- and nanotechnologies in terms of platform design, analytical method, and system integration and miniaturization. The continued development of new diagnostic platforms integrating micro- and nanocomponents will address some of the shortcomings we have witnessed in the existing COVID-19 diagnostic systems. This Perspective reviews the previous and ongoing research efforts on developing integrated micro- and nanosystems for nucleic acid-based virus detection, and highlights promising technologies that could provide better solutions for the diagnosis of COVID-19 and other viral infectious diseases. With the summary and outlook of this rapidly evolving research field, we hope to inspire more research and development activities to better prepare our society for future public health crises.

Title: Promising methods for detection of novel coronavirus SARS‐CoV‐2 Content: A very recent outbreak of the novel coronavirus, COVID‐19, in the city of Wuhan, China, in December 2019 and its subsequent spread within and across China have resulted in several deaths and infections. Presently, nucleic acid amplification test is essential for the confirmation of COVID infection. In this report, we summarized the six promising methods, including whole‐genome sequencing, real‐time reverse transcription polymerase chain reaction, nanopore target sequencing, antibody‐based immunoassay techniques, use of paper‐based biomolecular sensors, and the clustered regularly interspaced short palindromic repeats‐Cas system‐based technology, which can also be deployed for the detection of SARS‐CoV‐2. We further introduced the principles of these methods, discussed the scope and practicability of application of the available products and methods, and highlighted the potential approaches to develop additional products and techniques for early diagnosis of COVID‐19.

Title: Increasing testing throughput and case detection with a pooled-sample Bayesian approach in the context of COVID-19 Content: Rapid and widespread implementation of infectious disease surveillance is a critical component in the response to novel health threats. Molecular assays are the preferred method to detect a broad range of pathogens with high sensitivity and specificity. The implementation of molecular assay testing in a rapidly evolving public health emergency can be hindered by resource availability or technical constraints. In the context of the COVID-19 pandemic, the applicability of a pooled-sample testing protocol to screen large populations more rapidly and with limited resources is discussed. A Bayesian inference analysis in which hierarchical testing stages can have different sensitivities is implemented and benchmarked against early COVID-19 testing data. Optimal pool size and increases in throughput and case detection are calculated as a function of disease prevalence. Even for moderate losses in test sensitivity upon pooling, substantial increases in testing throughput and detection efficiency are predicted, suggesting that sample pooling is a viable avenue to circumvent current testing bottlenecks for COVID-19.

Title: Detection of COVID-19 Infection from Routine Blood Exams with Machine Learning: a Feasibility Study Content: Background - The COVID-19 pandemia due to the SARS-CoV-2 coronavirus, in its first 4 months since its outbreak, has to date reached more than 200 countries worldwide with more than 2 million confirmed cases (probably a much higher number of infected), and almost 200,000 deaths. Amplification of viral RNA by (real time) reverse transcription polymerase chain reaction (rRT-PCR) is the current gold standard test for confirmation of infection, although it presents known shortcomings: long turnaround times (3-4 hours to generate results), potential shortage of reagents, false-negative rates as large as 15-20%, the need for certified laboratories, expensive equipment and trained personnel. Thus there is a need for alternative, faster, less expensive and more accessible tests. Material and methods - We developed two machine learning classification models using hematochemical values from routine blood exams (namely: white blood cells counts, and the platelets, CRP, AST, ALT, GGT, ALP, LDH plasma levels) drawn from 279 patients who, after being admitted to the San Raffaele Hospital (Milan, Italy) emergency-room with COVID-19 symptoms, were screened with the rRT-PCR test performed on respiratory tract specimens. Of these patients, 177 resulted positive, whereas 102 received a negative response. Results - We have developed two machine learning models, to discriminate between patients who are either positive or negative to the SARS-CoV-2: their accuracy ranges between 82% and 86%, and sensitivity between 92% e 95%, so comparably well with respect to the gold standard. We also developed an interpretable Decision Tree model as a simple decision aid for clinician interpreting blood tests (even off-line) for COVID-19 suspect cases. Discussion - This study demonstrated the feasibility and clinical soundness of using blood tests analysis and machine learning as an alternative to rRT-PCR for identifying COVID-19 positive patients. This is especially useful in those countries, like developing ones, suffering from shortages of rRT-PCR reagents and specialized laboratories. We made available a Web-based tool for clinical reference and evaluation. This tool is available at https://covid19-blood-ml.herokuapp.com.

Title: Fast SARS-CoV-2 detection by RT-qPCR in preheated nasopharyngeal swab samples Content: OBJECTIVES: The gold-standard COVID-19 diagnosis relies on detecting SARS-CoV-2 using RNA purification and one-step retrotranscription and quantitative PCR (RT-qPCR). Based on the urgent need for high-throughput screening, we tested the performance of three alternative, simple and affordable protocols to rapidly detect SARS-CoV-2, bypassing the long and tedious RNA extraction step and reducing the time to viral detection. METHODS: We evaluated three methods based on direct nasopharyngeal swab viral transmission medium (VTM) heating before the RT-qPCR: a) direct without additives; b) in a formamide-EDTA (FAE) buffer, c) in a RNAsnapTM buffer. RESULTS: Although with a delay in cycle threshold compared to the gold-standard, we found consistent results in nasopharyngeal swab samples that were subject to a direct 70°C incubation for 10 min. CONCLUSIONS: Our findings provide valuable options to overcome any supply chain issue and help to increase the throughput of diagnostic tests, thereby complementing standard diagnosis.

Title: Clinical Testing For Covid-19 Content: Abstract As the novel coronavirus SARS-CoV-2 caused COVID-19 cases in the United States the initial test was developed and performed at the Center for Disease Control (CDC). As the number of cases increased the demand for tests multiplied, leading the CDC to utilize the Emergency Utilization Authorization to allow clinical and commercial laboratories to develop tests to detect the presence of the virus. Many nucleic acid tests based on reverse transcriptase-polymerase chain reaction (RT-PCR) were developed, each with different techniques, specifications and turnaround time. As the illnesses turned into a pandemic, testing became more crucial. The test supply became inadequate to meet the need that it had to be prioritized according to guidance. For surveillance, the need for serologic tests emerged. Here we review the timeline of test development, the turn-around times, the various approved tests and compare them as regards the genes they detect. We concentrate on the point-of-care tests and discuss the basis for new serologic tests. We discuss the testing guidance for prioritization and their application in a hospital setting. As SARS-CoV-2 virus arrived in the USA causing the COVID-19 illness, one of the most talked about issues in the management of the disease and the resulting pandemic has been clinical testing. A unique situation arose of a communicable and highly contagious disease necessitating the rapid diagnosis of patients and the identification of non-symptomatic infected persons. Unfortunately, the USA did not have a Food and Drug Administration (FDA) approved laboratory test for the illness. The FDA ultimately utilized its Emergency Use Authorizations (EUA) on February 4, 2020 to allow for more rapid and widespread development and implementation of in-vitro testing.1 Indeed, companies and organizations utilized the EUA to file applications for new tests based on different methodologies, amounting to 48 applications in the span of 3 months from the beginning of February to the end of April 2020. In addition, multiple other tests were put in place under a separate authorization by a Presidential memorandum in early March allowing laboratories that carry Clinical Laboratory Improvement Amendment (CLIA) certification to put tests in place without an EUA from the FDA. This created an unprecedented situation where the medical community and the public may not be familiar with the various new tests for COVID-19 that are offered to patients and hospitals. The purpose of this review is to provide information, up-to-date as of the date of submission of the manuscript to the journal, on the various tests that have been developed, their scientific basis and their interpretation. We give a real-world example demonstrating the time lag in the return of test results and review testing prioritization guidance since the supply of tests remains below the perceived need.

Title: Testing times in Coronavirus disease (Covid-19): A tale of two nations Content: The Coronavirus Disease (Covid-19) pandemic is caused by the severe acute respiratory syndrome virus 2 and was first identified in Wuhan, China, in December 2019. The disease spread globally, leading to the World Health Organization declaring it a pandemic in March 2020. The condition is often fatal in its severe form. As it is a previously unknown virus, no treatment is identified or any vaccine available. The burden of disease control and containment, therefore, falls upon a robust and geographically appropriate testing strategy. Testing policies are modified, in turn, by the rapidly evolving patterns of the disease in various nations and by the evolving nature of tests in development. It is, therefore, helpful to study different national models to learn from the experience of different countries. This article compares testing strategies in the UK and India as the two countries travel different paths in controlling the pandemic. The UK is one of the most severely affected countries in the world. Initially restricted to hospitalised patients, the UK has broadened the scope of testing to many categories of individuals. In contrast, India appears to have a lower prevalence of the infection. However, the large Indian population and relatively insufficient testing capacities so far have led India to adopt a different testing trajectory, with the testing currently focused on high-risk groups in the community and hospitals. Owing to the rapidly changing nature of the disease, there can be no ‘one-size-fits-all’ policy but should be based on country-specific circumstances.

Title: Field-deployable, rapid diagnostic testing of saliva samples for SARS-CoV-2. Content: Abstract Rapid, scalable, point-of-need, COVID-19 diagnostic testing is necessary to safely re-open economies and prevent future outbreaks. We developed an assay that detects single copies of SARS-CoV-2 virus directly from saliva and swab samples in 30 min using a simple, one-step protocol that utilizes only a heat block and microcentrifuge tube prefilled with a mixture containing the necessary reagents and has a sensitivity and specificity of 97% and 100%, respectively.