A New Software Interface for Registering Rapid Antigen Test Results to Prevent Fraud.

Donald O. Besong has already documented that the online registration of unsupervised lateral flow test results poses concerns in the case of a serious pandemic where there are not enough medics to read scans or watch videos of candidates' results [1]. Scanning or videorecording requires a high number of available medics [1] in an adverse pandemic scenario. In the above paper [1], an artificial intelligence (AI) interface with image recognition was suggested as a method to prevent cheating during the online registration of unsupervised test results. The second solution suggested was a method that obscures the meaning of the result the candidate reads from their test device so that a software interface can resolve that from a database [1]. This is an entirely new method.In this paper, the latter (entirely new) method is proposed and described in detail. Precisely, this simple but new method is all about blinding the test strips so that the candidate does not know what the face values signify. The software then connects to a database of unique strip identification numbers to determine the test result when the candidate or patient registers their results. Both strip number and the value of their test must be entered to register results. This method has never been proposed or implemented. The technique will be described in detail.

Laboratory Evaluation Links Some False-Positive COVID-19 Antigen Test Results Observed in a Field Study to a Specific Lot of Test Strips.

During a household-transmission field study using COVID-19 antigen rapid diagnostic tests (Ag-RDT), a common test strip lot was identified among 3 participants with false-positive results. In blinded laboratory evaluation, this lot exhibited a significantly higher false-positive rate than other lots. Because a positive Ag-RDT result often prompts action, reducing lot-specific false positives can maintain confidence and actionability of true-positive Ag-RDT results.

Stakeholder perspectives of piloting pre-hospital COVID-19 lateral flow testing and direct admissions pathway: exploring why well-received ideas have low uptake.

Introduction: In January 2021, Yorkshire Ambulance Service and Hull University Teaching Hospitals implemented a pilot COVID-19 lateral flow testing (LFT) and direct admissions pathway to assess the feasibility of using pre-hospital LFTs to bypass the emergency department. Due to lower than anticipated uptake of the pilot among paramedics, we undertook a process evaluation to assess reasons for low uptake and perceived potential benefits and risks associated with the pilot. Methods: We undertook semi-structured telephone interviews with 12 paramedics and hospital staff. We aimed to interview paramedics who had taken part in the pilot, those who had received the project information but not taken part and ward staff receiving patients from the pilot. We transcribed interviews verbatim and analysed data using thematic analysis. Results: Participation in the pilot appeared to be positively influenced by high personal capacity for undertaking research (being 'research-keen') and negatively influenced by 'COVID-19 exhaustion', electronic information overload and lack of time for training. Barriers to use of the pathway related to 'poor timing' of the pilot, restrictive patient eligibility and inclusion criteria. The rapid rollout meant that paramedics had limited knowledge or awareness of the pilot, and pilot participants reported poor understanding of the pilot criteria or the rationale for the criteria. Participants who were involved in the pilot were overwhelmingly positive about the intervention, which they perceived as having limited risks and high potential benefits to the health service, patients and themselves, and supported future roll-out. Conclusions: Ambulance clinician involvement in rapid research pilots may be improved by using multiple recruitment methods (electronic and other), providing protected time for training and increased direct support for paramedics with lower personal capacity for research. Improved communication (including face-to-face approaches) may help understanding of eligibility criteria and increase appropriate recruitment.

The Performance of Lateral Flow Tests in the Age of the Omicron: A Rapid Systematic Review.

Prompt detection and isolation of COVID-19 cases is vital for preventing further viral transmission, and lateral flow or rapid antigen tests have been an important diagnostic tool in this pandemic. However, concerns have emerged regarding the sensitivity of these devices for the new BA.1, BA.2, and BA.4/5 omicron variants, which have greater transmissibility and extensive mutations in its spike (S) and nucleocapsid (N) proteins. N protein is an important target protein for existing lateral flow devices. This paper therefore aimed to provide a rapid review of available literature on the performance of the lateral flow tests for detecting the omicron coronavirus variant. A systematic literature search of PubMed, EMBASE, OVID Medline, and Google Scholar found six published studies and four preprints investigating the performance of existing lateral flow devices for the omicron variant, as compared to the B.1.617.2 (Delta) variant. Overall, it appears that the devices have poorer performance for the omicron variant and when testing samples with cycle threshold (Ct) values greater than 25 and in asymptomatic individuals. As most available data were preliminary and had small sample sizes, it is recommended that these data be further studied to better inform and adapt our public health responses.

COVID-19 Rapid Antigen Tests: Bibliometric Analysis of the Scientific Literature.

As the COVID-19 pandemic continues to disrupt health systems worldwide, conducting Rapid Antigen Testing (RAT) at specified intervals has become an essential part of many people's lives around the world. We identified and analyzed the academic literature on COVID-19 RAT. The Web of Science electronic database was queried on 6 July 2022 to find relevant publications. Publication and citation data were retrieved directly from the database. VOSviewer, a bibliometric software, was then used to relate these data to the semantic content from the titles, abstracts, and keywords. The analysis was based on data from 1000 publications. The most productive authors were from Japan and the United States, led by Dr. Koji Nakamura from Japan (n = 10, 1.0%). The most academically productive countries were in the North America, Europe and Asia, led by the United States of America (n = 266, 26.6%). Sensitivity (n = 32, 3.2%) and specificity (n = 23, 2.3%) were among the most frequently recurring author keywords. Regarding sampling methods, "saliva" (n = 54, 5.4%) was mentioned more frequently than "nasal swab" (n = 32, 3.2%) and "nasopharyngeal swab" (n = 22, 2.2%). Recurring scenarios that required RAT were identified: emergency department, healthcare worker, mass screening, airport, traveler, and workplace. Our bibliometric analysis revealed that COVID-19 RAT has been utilized in a range of studies. RAT results were cross-checked with RT-PCR tests for sensitivity and specificity. These results are consistent with comparable exchanges of methods, results or discussions among laboratorians, authors, institutions and publishers in the involved countries of the world.

Cost-effectiveness of a whole-area testing pilot of asymptomatic SARS-CoV-2 infections with lateral flow devices: a modelling and economic analysis study.

BACKGROUND: Mass community testing for SARS-CoV-2 by lateral flow devices (LFDs) aims to reduce prevalence in the community. However its effectiveness as a public heath intervention is disputed. METHOD: Data from a mass testing pilot in the Borough of Merthyr Tydfil in late 2020 was used to model cases, hospitalisations, ICU admissions and deaths prevented. Further economic analysis with a healthcare perspective assessed cost-effectiveness in terms of healthcare costs avoided and QALYs gained. RESULTS: An initial conservative estimate of 360 (95% CI: 311-418) cases were prevented by the mass testing, representing a would-be reduction of 11% of all cases diagnosed in Merthyr Tydfil residents during the same period. Modelling healthcare burden estimates that 24 (16-36) hospitalizations, 5 (3-6) ICU admissions and 15 (11-20) deaths were prevented, representing 6.37%, 11.1% and 8.2%, respectively of the actual counts during the same period. A less conservative, best-case scenario predicts 2333 (1764-3115) cases prevented, representing 80% reduction in would-be cases. Cost -effectiveness analysis indicates 108 (80-143) QALYs gained, an incremental cost-effectiveness ratio of £2,143 (£860-£4,175) per QALY gained and net monetary benefit of £6.2 m (£4.5 m-£8.4 m). In the best-case scenario, this increases to £15.9 m (£12.3 m-£20.5 m). CONCLUSIONS: A non-negligible number of cases, hospitalisations and deaths were prevented by the mass testing pilot. Considering QALYs gained and healthcare costs avoided, the pilot was cost-effective. These findings suggest mass testing with LFDs in areas of high prevalence (> 2%) is likely to provide significant public health benefit. It is not yet clear whether similar benefits will be obtained in low prevalence settings or with vaccination rollout.

Development of gold nanoparticles-lateral flow test as a novel field diagnostic assay for detecting foot-and-mouth disease and lumpy skin disease viruses

Background and Objectives: Rapid diagnosis is a cornerstone for controlling and preventing viral disease outbreaks. The present study is aimed to develop a rapid field diagnostic test based on gold nanoparticles for the detection of lumpy skin diseases (LSD), and foot and mouth diseases (FMD) in animals with high sensitivity and specificity. Materials and Methods: FMD and LSD vaccines were used as a source of viruses' antigens for preparing monoclonal antibodies and conjugated with gold nanoparticles that characterized using various techniques such as UV-visible spectrometry, and transmission electron microscopy (TEM). Monoclonal antibodies (mAbs) for each serotype produced in experimental rats and used to capture antibodies for FMDV and /or LSDV. ELISA was used to screen 469 milk samples and 1165 serum samples from naturally infected cattle, buffaloes, sheep, and goats for validation of the lateral flow test (LFT). LSDV DNA was extracted from 117 blood and skin biopsy samples collected from naturally infected cattle during the 2019 outbreak. Results: The specificity and sensitivity of GNP-LFT were evaluated and compared to Ag-ELISA, Western blot tests (WB), and PCR. A total of 95 FMDV positives out of 469 (20.25%) milk samples and 268 FMDV positives out of 1165 (23.3%) serum samples from natural infected cattle, buffaloes, sheep, and goats examined by ELISA to valid GNPS-LFT Viral LSDV DNA was detected in 60/117 (51.5%) and 31/60 (52.9%). While the GNPS-LFT assay results were 49/117 (41.9%) and 29/60 (48.3%) blood and skin biopsy samples, respectively. The diagnostic sensitivity and specificity of the GNP-LFT test were 72% and 82%, respectively. All vesicular fluid and epithelium samples collected from infected animals were identified as positive by the GNP-LFT and Ag-ELISA. Ag-ELISA, on the other hand, was 90% and 100%. While the developed GNPLFT used LSDV polyclonal antibodies were similar to ELISA and IgG-WB with a sensitivity of 72.8% and a specificity of 88.8%, respectively. Conclusion: The GNPS-LFT is a novel immunoassay based on mono or polyclonal antibodies conjugated with gold nanoparticles that provides an accurate, rapid, specific, and sensitive tool for field rapid diagnosis of FMDV and LSDV. [ FROM AUTHOR] Copyright of Iranian Journal of Microbiology is the property of Tehran University of Medical Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Lateral Flow Test Interpretation with Residual Networks

Lateral flow tests (LFTs) are a cost-effective, quick, and frequently used testing method in many domains such as food safety and environmental and clinical applications. However, a major challenge is accurate interpretation of LFT results. Often, if a low level of target substance is present in the input liquid, the test line indicator may appear faint, causing a test interpreter to read the test result as a false negative. Therefore, to address this problem, we propose a deep-learning-based method to interpret images of LFT results. Our model is based on ResNet-101, a state-of-the-art image classification model that uses residual networks, or skip-connections between layers to improve learning on the training dataset. We further improve our model by using data augmentation to generate additional and more difficult images of LFTs for the model to learn from, thereby improving its performance and reducing overfitting to the training dataset. Our approach is also trained and tested on a dataset of SARS-CoV-2 LFT images, containing both positive and negative results. We compare our ResNet approach to a baseline convolutional neural network model. Our results show the ResNet model achieves a higher specificity and sensitivity than the baseline model to interpret LFT results. © 2021 IEEE.

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

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

Diagnoses Based on C-Reactive Protein Point-of-Care Tests.

C-reactive protein (CRP) is an important part of the immune system's reaction to various pathological impulses such as bacterial infections, systemic inflammation, and internal organ failures. An increased CRP level serves to diagnose the mentioned pathological states. Both standard laboratory methods and simple point-of-care devices such as lateral flow tests and immunoturbidimetric assays serve for the instrumental diagnoses based on CRP. The current method for CRP has many flaws and limitations in its use. Biosensor and bioassay analytical devices are presently researched by many teams to provide more sensitive and better-suited tools for point-of-care tests of CRP in biological samples when compared to the standard methods. This review article is focused on mapping the diagnostical relevance of CRP, the applicability of the current analytical methods, and the recent innovations in the measurement of CRP level.

Detection of COVID Disease from CT Scan Images using CNN Model

The world is affected by an existential global health crisis called the COVID-19 pandemic. Countries like the United States, India and Russia are still having and gaining positive COVID cases, which results in the deaths of hundreds and thousands of people. Admitting the actuality that there are several vaccinations on the market at the moment, positive cases continue to rise. Consequently, there is a critical need for quick infection detection with clear visualization so that a suspected COVID-19 patient can be spared. Tests, namely Polymerase chain reaction (PCR), Lateral flow tests (LFTs), need to send to a laboratory for examination, so patients may have to wait for a few days to get their results, but still, the final results aren't accurate. CT Scan pictures are a commonly utilized imaging modality among previously existing, low-cost and widely available resources, but deep learning approaches have attained state-of-the-art performance in computer-aided medical diagnosis. The goal of our paper is to employ CNN (Convolutional Neural Network) and find whether the patient has COVID-19 or not by using CT scan pictures. The suggested method employs convolutional neural networks as part of its deep learning techniques. COVID19 was diagnosed using the CNN model with various filters, and they achieved accuracy with 85.34%, 87.46% and 88.15%, respectively. Doctors can employ COVID-19 automated diagnosis using CT scan pictures as a quick and effective technique to detect COVID-19 © 2022 IEEE.

Evaluation of SARS-CoV-2 diagnostics and risk factors associated with SARS-CoV-2 infection in Zambia.

OBJECTIVES: To conduct a diagnostic validation study of SARS-CoV-2 diagnostic kits. METHODS: We compared SARS-CoV-2 diagnostic test results from 3 RT-PCR assays used by the Zambian government between November 2020 and February 2021 (Panther Fusion assay, Da An Gene's 2019-nCoV RNA kit and Maccura's PCR Kit) with the Altona RealStar RT-PCR kit which served as the gold standard. We also evaluated results from rapid antigen testing and whether comorbidities were linked with increased odds of infection. RESULTS: We recruited 244 participants, 61% (149/244) were positive by at least 1 PCR assay. Da An Gene, Maccura, and Panther Fusion assays had sensitivities of 0.0% (95% confidence interval [CI] 0%-41%), 27.1% (95% CI 15%-42%), and 76% (95% CI 65%-85%), respectively, but specificity was low (<85% for all 3 assays). HIV and TB were not associated with SARS-CoV-2, whereas female sex (OR 0.5 [0.3-0.9], p = 0.026) and chronic pulmonary disease (0.1 [0.0-0.8], p = 0.031) were associated with lower odds of SARS-CoV-2 infection. Of 44 samples, 84% sequenced were Beta variant. CONCLUSIONS: The RT-PCR assays evaluated did not meet WHO recommended minimum sensitivity of 80%. Local diagnostic validation studies should be embedded within preparedness plans for future outbreaks to improve the public health response.

Evaluation of feasibility and user acceptance of lateral-flow self-testing for viral illness in a residential treatment rehabilitation facility.

BACKGROUND: The role of rapid testing has proven vital in reducing infection incidence in communities through swift identification and isolation of infected individuals. The COVID-19 pandemic has been particularly catastrophic for residential carceral and rehabilitation facilities that are high-risk settings for transmission of contagious diseases. Centralized provider-based viral testing employing conventional diagnostic techniques is labor-intensive and time-consuming. There is a marked unmet need for quick, inexpensive, and simple viral testing strategies. We hypothesized that rehabilitation residents could successfully test themselves employing inexpensive, disposable, antigen-based influenza lateral-flow tests and would be willing to self-isolate and self-report to health authorities if positive. METHODS: We evaluated self-testing among 50 rehabilitation residents ages 18 and older in Pomona, California, where participants self-administered influenza lateral-flow diagnostic test (without specimen collection) with the goal of appropriately observing a control line and completed two brief written surveys on self-testing and COVID-19, one before self-administering the lateral-flow test and one after, to determine the overall feasibility of viral self-testing and to characterize attitudes comparing self-testing and provider-based testing. FINDINGS: A total of 50 rehabilitation residents were enrolled in this study and all 50 conducted a lateral-flow test and answered the provided surveys. Among the participants, 96% (48 of 50) achieved a positive-control line from their lateral-flow test. Most participants, 83% (34 of 41) indicated that they would prefer to perform their own rapid test instead of having a health care provider administer the test. Notably, 98% (49 of 50) indicated that they would self-isolate if the lateral-flow test returned a positive indicator suggesting the presence of a viral infection and 96% (48 of 50) would report positive results to their corresponding public health department. INTERPRETATION: Residents in a residential rehabilitation center were widely able to successfully self-administer standard lateral-flow antigen-based rapid diagnostic kits. Self-testing was strongly preferred over tests administered by a healthcare provider. Reassuringly, almost every resident indicated that they would report any positive test result to the health department and self-isolate accordingly. Self-testing offers a promising adjunct to centralized testing, potentially better enabling swift and effective management of life-threatening infectious outbreaks among those living in high-risk congregate living settings.

SARS-CoV-2 antibody kinetics in blood donors with a previously positive SARS-CoV-2 antibody test within a seroprevalence survey.

The persistence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies is a matter of importance regarding the coronavirus disease 19 (COVID-19) pandemic. To observe antibody dynamics, 105 blood donors, positive for SARS-CoV-2 antibodies by a lateral flow test within a seroprevalence study, were included in this study. Thirty-nine (37%) of 105 the donors were confirmed positive by a total Ig Wantai enzyme-linked immunosorbent assay (ELISA). Three (8%) in this group of 39 reported severe and 26/39 (67%) mild to moderate COVID-19 symptoms. By further ELISA-testing, 33/39 (85%) donors were initially positive for IgG antibodies, 31/39 (79%) for IgA, and 32/39 (82%) for IgM, while 27/39 (69%) were positive for all three isotypes. Persistence of IgG, IgA, and IgM was observed in 73%, 79%, and 32% of donors, respectively, after 6-9 months of observation. For IgM antibodies, the decline in the proportion of positive donors was statistically significant (p = 0.002) during 12 months observation, for IgG only the decline at 3 months was statistically significant (p = 0.042). Four donors exhibited notable increases in antibody levels. In conclusion, persistent SARS-CoV-2 IgA antibodies and IgG antibodies at 6-9 months are present in approximately three of four individuals with previous mild to moderate COVID-19.

Improving the Quantification of Colorimetric Signals in Paper-Based Immunosensors with an Open-Source Reader.

Measuring the colorimetric signals produced by the biospecific accumulation of colorimetric probes and recording the results is a key feature for next-generation paper-based rapid tests. Manual processing of these tests is time-consuming and prone to a loss of accuracy when interpreting faint and patchy signals. Proprietary, closed-source readers and software companies offering automated smartphone-based assay readings have both been criticized for interoperability issues. Here, we introduce a minimal reader prototype composed of open-source hardware and open-source software that has the benefits of automatic assay quantification while avoiding the interoperability issues associated with closed-source readers. An image-processing algorithm was developed to automate the selection of an optimal region of interest and measure the average pixel intensity. When used to quantify signals produced by lateral flow immunoassays for detecting antibodies against SARS-CoV-2, results obtained with the proposed algorithm were comparable to those obtained with a manual method but with the advantage of improving the precision and accuracy when quantifying small spots or faint and patchy signals.

A wearable AIEgen-based lateral flow test strip for rapid detection of SARS-CoV-2 RBD protein and N protein.

Accurate and rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is significant for early tracing, isolation, and treatment of infected individuals, which will efficiently prevent large-scale transmission of coronavirus disease 2019 (COVID-19). Here, two kinds of test strips for receptor binding domain (RBD) and N antigens of SARS-CoV-2 are established with high sensitivity and specificity, in which AIE luminogens (AIEgens) are utilized as reporters. Because of the high brightness and resistance to quenching in aqueous solution, the limit of detection can be as low as 6.9 ng/mL for RBD protein and 7.2 ng/mL for N protein. As an antigen collector, an N95 mask equipped with a test strip with an excellent enrichment effect would efficiently simplify the sampling procedures. Compared with a test strip based on Au nanoparticles or fluorescein isothiocyanate (FITC), the AIEgen-based test strip shows high anti-interference capacity in complex biosamples. Therefore, an AIEgen-based test strip assay could be built as a promising platform for emergency use during the pandemic.

Feasibility and Acceptability of Community Coronavirus Disease 2019 Testing Strategies (FACTS) in a University Setting.

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic in 2020, the UK government began a mass severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing program. This study aimed to determine the feasibility and acceptability of organized regular self-testing for SARS-CoV-2. METHODS: This was a mixed-methods observational cohort study in asymptomatic students and staff at University of Oxford, who performed SARS-CoV-2 antigen lateral flow self-testing. Data on uptake and adherence, acceptability, and test interpretation were collected via a smartphone app, an online survey, and qualitative interviews. RESULTS: Across 3 main sites, 551 participants (25% of those invited) performed 2728 tests during a follow-up of 5.6 weeks; 447 participants (81%) completed at least 2 tests, and 340 (62%) completed at least 4. The survey, completed by 214 participants (39%), found that 98% of people were confident to self-test and believed self-testing to be beneficial. Acceptability of self-testing was high, with 91% of ratings being acceptable or very acceptable. A total of 2711 (99.4%) test results were negative, 9 were positive, and 8 were inconclusive. Results from 18 qualitative interviews with students and staff revealed that participants valued regular testing, but there were concerns about test accuracy that impacted uptake and adherence. CONCLUSIONS: This is the first study to assess feasibility and acceptability of regular SARS-CoV-2 self-testing. It provides evidence to inform recruitment for, adherence to, and acceptability of regular SARS-CoV-2 self-testing programs for asymptomatic individuals using lateral flow tests. We found that self-testing is acceptable and people were able to interpret results accurately.

First Dose of BNT162b2 mRNA Vaccine in a Healthcare Worker Cohort Is Associated With Reduced Symptomatic and Asymptomatic Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection.

Over the first 2 months of 2021, vaccination coverage of staff at Hull Teaching Hospitals with BNT162b2 increased from 8.3% to 82.5% and was associated with a significant reduction in symptomatic and asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cases. The proportion of positive lateral flow tests from asymptomatic screening was maintained over this period.

Point-of-care diagnosis of COVID-19 disease based on antigen tests.

AIMS: This review is focused on the laboratory diagnoses of the coronavirus disease 2019 (COVID-19) by recognizing the antigen of the causative agent SARS-CoV-2 virus. Various antigen tests are available in this moment and these tests are being further developed in order to reach a better diagnostic value. The issue is reviewed in a complex view. METHODS: In this work, a complex survey of the current literature was made. The relevant and recent papers related to antigen tests of COVID-19 are discussed and cited. Basic specifications of the antigen tests and competitive methods were also scrutinized in the current literature. RESULTS: The survey of the current literature (years 2019 ‒ 2021) was made and diagnostic methods like lateral flow tests (lateral flow immunochromatographic assay) and various types of biosensors were specified as tools for COVID-19 diagnosis and their application to be used as a point-of-care test is considered. CONCLUSIONS: Small hand-held assays applicable in the point-of-care conditions for diagnosis of COVID-19 by analysis of SARS-CoV-2 antigen are the means of a growing interest and these means undergo a significant development leading to the improvements of their specifications and applicability to the current praxis. Merit of the assays is discussed in this paper (Tab. 3, Fig. 2, Ref. 109).

Development and Efficacy of Lateral Flow Point-of-Care Testing Devices for Rapid and Mass COVID-19 Diagnosis by the Detections of SARS-CoV-2 Antigen and Anti-SARS-CoV-2 Antibodies.

The COVID-19 pandemic is an ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2020-2021. COVID-19 is becoming one of the most fatal pandemics in history and brings a huge challenge to the global healthcare system. Opportune detection, confinement, and early treatment of infected cases present the first step in combating COVID-19. Diagnosis via viral nucleic acid amplification tests (NAATs) is frequently employed and considered the standard procedure. However, with an increasing urge for point-of-care tests, rapid and cheaper immunoassays are widely utilized, such as lateral flow immunoassay (LFIA), which can be used for rapid, early, and large-scale detection of SARS-CoV-2 infection. In this narrative review, the principle and technique of LFIA applied in COVID-19 antigen and antibody detection are introduced. The diagnostic sensitivity and specificity of the commercial LFIA tests are outlined and compared. Generally, LFIA antigen tests for SARS-CoV-2 are less sensitive than viral NAATs, the "gold standard" for clinical COVID-19 diagnosis. However, antigen tests can be used for rapid and mass testing in high-risk congregate housing to quickly identify people with COVID-19, implementing infection prevention and control measures, thus preventing transmission. LFIA anti-SARS-CoV-2 antibody tests, IgM and/or IgG, known as serology tests, are used for identification if a person has previously been exposed to the virus or vaccine immunization. Notably, advanced techniques, such as LFT-based CRISPR-Cas9 and surface-enhanced Raman spectroscopy (SERS), have added new dimensions to the COVID-19 diagnosis and are also discussed in this review.