scholarly journals Point-of-Care Diagnostic Tools for Surveillance of SARS-CoV-2 Infections

2021 ◽  
Vol 9 ◽  
Author(s):  
Dhanasekaran Sakthivel ◽  
David Delgado-Diaz ◽  
Laura McArthur ◽  
William Hopper ◽  
Jack S. Richards ◽  
...  
Keyword(s):  
Large Scale ◽  
Clinical Symptoms ◽  
Point Of Care ◽  
Cost Effective ◽  
Nucleic Acid Amplification ◽  
Diagnostic Tools ◽  
Rt Pcr ◽  
Serological Tests ◽  
Polymerase Chain ◽  
Effective Public Health

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a recently emerged and highly contagious virus that causes coronavirus disease 2019 (COVID-19). As of August 24, 2021, there were more than 212 million confirmed COVID-19 cases and nearly 4.4 million deaths reported globally. Early diagnosis and isolation of infected individuals remains one of the most effective public health interventions to control SARS-CoV-2 spread and for effective clinical management of COVID-19 cases. Currently, SARS-CoV-2 infection is diagnosed presumptively based on clinical symptoms and confirmed by detecting the viral RNA in respiratory samples using reverse transcription polymerase chain reaction (RT-PCR). Standard RT-PCR protocols are time consuming, expensive, and technically demanding, which makes them a poor choice for large scale and point-of-care screening in resource-poor settings. Recently developed isothermal nucleic acid amplification tests (iNAAT), antigen and/or serological tests are cost-effective to scale COVID-19 testing at the point-of-care (PoC) and for surveillance activities. This review discusses the development of rapid PoC molecular tools for the detection and surveillance of SARS-CoV-2 infections.

scholarly journals Comparative analysis of three point-of-care lateral flow immunoassays for detection of anti-SARS-CoV-2 antibodies in COVID-19 confirmed healthcare workers

2020 ◽  
Author(s):  
Danielle Dias Conte ◽  
Joseane Mayara Almeida Carvalho ◽  
Luciano Kleber de Souza Luna ◽  
Klinger Soares Faíco-Filho ◽  
Ana Helena Perosa ◽  
...  
Keyword(s):  
Healthcare Workers ◽  
Large Scale ◽  
Point Of Care ◽  
Antibody Test ◽  
Cost Effective ◽  
Lateral Flow ◽  
Rt Pcr ◽  
Serum Samples ◽  
Igg Antibody ◽  
Serological Tests

AbstractSince the Coronavirus Disease 2019 (COVID-19) pandemic, Brazil has the third-highest number of confirmed cases and the second-highest number of recovered patients. SARS-CoV-2 detection by real-time RT-PCR is the gold standard in certified infrastructured laboratories. However, for large-scale testing, diagnostics should be fast, cost-effective, widely available, and deployed for the community, such as serological tests based on lateral flow immunoassay (LFIA) for IgM/IgG detection. We evaluated three different commercial point-of-care (POC) LFIAs for anti-SARS-CoV-2 IgM and IgG detection in capillary whole blood of 100 healthcare workers (HCW) previously tested by RT-PCR: 1) COVID-19 IgG/IgM BIO (Bioclin, Brazil), 2) Diagnostic kit for IgM/IgG Antibody to Coronavirus (SARS-CoV-2) (Livzon, China); and 3) SARS-CoV-2 Antibody Test (Wondfo, China). A total of 84 positives and 16 negatives HCW were tested. The data was also analyzed by the number of days post symptoms (DPS) in three groups: <30 (n=26), 30-59 (n=42), and >59 (n=16). Overall detection was 85.71%, 47.62%, and 44.05% for Bioclin, Livzon, and Wondfo, respectively, with a specificity of 100%, and 98.75% for Livzon on storage serum samples. Bioclin was more sensitive (p<0.01), regardless of the DPS. Thus, the Bioclin can be used as a POC test to monitor SARS-CoV-2 seroconversion in HCW.

scholarly journals Point-of-Care Diagnostics of COVID-19: From Current Work to Future Perspectives

Sensors ◽  
2020 ◽  
Vol 20 (15) ◽  
pp. 4289 ◽  
Author(s):  
Heba A. Hussein ◽  
Rabeay Y. A. Hassan ◽  
Marco Chino ◽  
Ferdinando Febbraio
Keyword(s):  
Point Of Care ◽  
Virus Detection ◽  
Diagnostic Tools ◽  
Sample Treatment ◽  
Rt Pcr ◽  
Point Of Care Diagnostics ◽  
Electrochemical Immunosensors ◽  
Global Concern ◽  
Polymerase Chain ◽  
Reliable Methods

Coronaviruses have received global concern since 2003, when an outbreak caused by SARS-CoV emerged in China. Later on, in 2012, the Middle-East respiratory syndrome spread in Saudi Arabia, caused by MERS-CoV. Currently, the global crisis is caused by the pandemic SARS-CoV-2, which belongs to the same lineage of SARS-CoV. In response to the urgent need of diagnostic tools, several lab-based and biosensing techniques have been proposed so far. Five main areas have been individuated and discussed in terms of their strengths and weaknesses. The cell-culture detection and the microneutralization tests are still considered highly reliable methods. The genetic screening, featuring the well-established Real-time polymerase chain reaction (RT-PCR), represents the gold standard for virus detection in nasopharyngeal swabs. On the other side, immunoassays were developed, either by screening/antigen recognition of IgM/IgG or by detecting the whole virus, in blood and sera. Next, proteomic mass-spectrometry (MS)-based methodologies have also been proposed for the analysis of swab samples. Finally, virus-biosensing devices were efficiently designed. Both electrochemical immunosensors and eye-based technologies have been described, showing detection times lower than 10 min after swab introduction. Alternative to swab-based techniques, lateral flow point-of-care immunoassays are already commercially available for the analysis of blood samples. Such biosensing devices hold the advantage of being portable for on-site testing in hospitals, airports, and hotspots, virtually without any sample treatment or complicated lab precautions.

scholarly journals Detection of SARS-CoV2 antigen in human saliva may be a reliable tool for large scale screening

2020 ◽  
Author(s):  
Priya Kannian ◽  
Chandra Lavanya ◽  
Krittika Ravichandran ◽  
Bagavad Gita Jayaraman ◽  
Pasuvaraj Mahanathi ◽  
...  
Keyword(s):  
Large Scale ◽  
Point Of Care ◽  
Human Saliva ◽  
Oral Diseases ◽  
Rt Pcr ◽  
Reliable Tool ◽  
Self Testing ◽  
Scale Population ◽  
Dental Screening ◽  
Polymerase Chain

AbstractIntroductionSARS-CoV2, the aetiological agent of the current COVID-19 pandemic, has been detected in saliva and recently implicated in several oral diseases. Collection of nasopharyngeal swabs (NPS) and detection by reverse transcriptase-polymerase chain reaction (RT-PCR) requires medical / technical expertise. A reliable and easy to handle point-of-care (POC) test is highly desirable, especially to curb transmission. Therefore, in this study, we evaluated a commercially available POC rapid antigen test (RAT) for the detection of SARS-CoV2 antigens in the saliva of RT-PCR confirmed positive and negative patients.MethodsThirty saliva samples of 10 saliva RT-PCR negative and 20 saliva RT-PCR positive patients were tested by RAT.ResultsRAT was negative in 10/10 (100%) RT-PCR-negative samples; positive in 9/20 (45%) RT-PCR-positive samples; concordance was 63% (p=0.001). Patients with positive RAT had higher virus copies in their NPS samples compared to the RAT-negative patients. This difference was also statistically significant (p=0.01).ConclusionThus, the POC RAT may be used to detect SARS-CoV2 as a reliable tool for self-testing, large-scale population screening and emergency medical/dental screening. Patients negative by RAT should be confirmed by RT-PCR.

scholarly journals An Update on Advances in COVID-19 Laboratory Diagnosis and Testing Guidelines in India

2021 ◽  
Vol 9 ◽  
Author(s):  
K. S. Rajesh Kumar ◽  
Suhail Sayeed Mufti ◽  
Vinu Sarathy ◽  
Diganta Hazarika ◽  
Radheshyam Naik
Keyword(s):  
Large Scale ◽  
Vaccine Development ◽  
Point Of Care ◽  
Diagnostic Testing ◽  
Public Health Intervention ◽  
Laboratory Diagnosis ◽  
Accurate Diagnosis ◽  
Nucleic Acid Amplification ◽  
Rt Pcr ◽  
Outbreak Management

The declaration of COVID-19 as a global pandemic has warranted the urgent need for technologies and tools to be deployed for confirming diagnosis of suspected cases. Diagnostic testing for COVID-19 is critical for understanding epidemiology, contract-tracing, case management, and to repress the transmission of the SARS-CoV-2. Currently, the Nucleic Acid Amplification Test (NAAT)-based RT-PCR technique is a gold standard test used for routine diagnosis of COVID-19 infection. While there are many commercially available RT-PCR assay kits available in the market, selection of highly sensitive, specific, and validated assays is most crucial for the accurate diagnosis of COVID-19 infection. Laboratory diagnosis of SARS-CoV-2 is extremely important in the disease and outbreak management. Development of rapid point of care tests with better sensitivity and specificity is the critical need of the hour as this will help accurate diagnosis and aid in containing the spread of SARS-CoV-2 infection. Early detection of viral infection greatly enhances implementation of specific public health intervention, such as infection control, environmental decontamination, and the closure of specific high-risk zones. Large-scale sequencing of SARS-CoV-2 genome isolated from affected populations across the world needs to be carried to monitor mutations that might affect performance of molecular tests. Creation of genome repositories and open-source genetic databases for use by global researchers is clearly the way forward to manage COVID-19 outbreak and accelerate vaccine development. This review summarizes various molecular diagnostics methods, technical guidelines, and advanced testing strategies adopted in India for laboratory diagnosis of COVID-19.

scholarly journals Molecular technologies for detection and typing of bluetongue virus

2017 ◽  
Vol 73 (5) ◽  
pp. 259-264
Author(s):  
Wiesław Niedbalski
Keyword(s):  
Large Scale ◽  
Synthesis Method ◽  
Lamp Assay ◽  
Cost Effective ◽  
Laboratory Diagnosis ◽  
Molecular Techniques ◽  
Nucleic Acid Hybridization ◽  
Diagnostic Tools ◽  
Rt Pcr ◽  
Animal Pathogens

Rapid and accurate diagnosis plays an important role in the implementation of effective measures to control the spread of disease. Historically, the laboratory diagnosis and typing of BTV were carried out by various serological and virological methods, including virus neutralization (VN) assay, ELISA, as well as virus isolation (VI) in cell cultures or in embryonated chicken eggs. At present, various molecular techniques to detect BTV genome are increasingly used as primary diagnostic tools for the serotyping and epidemiological investigations of BTV. Initially, the viral RNA was detected by simple nucleic acid hybridization technologies. Then, conventional RT-PCR assays were developed and evaluated for the detection of BTV serotypes based on nucleotide sequences of different genome segments. Although RT-PCR, with its increased sensitivity, has advantages over hybridization, it is almost impossible to quantify accurately by regular and multiplex PCR procedures, and regular PCR may produce false positive results. Over the recent years, a number of real-time RT-PCR (rRT-PCR) methods have been described. The rRT-PCR offers certain advantages over conventional RT-PCR assay, as it is more rapid, sensitive, and can provide quantitative as well as qualitative genetic information. It does not use agarose gel electrophoresis, decreases the risk of contamination because it is run within an enclosed tube, and is suitable for large-scale testing and automation. The target amplicon is usually smaller, reducing the potential for problems caused by target degradation. Loop-mediated isothermal amplification (LAMP), a novel rapid, accurate and cost effective gene amplification method, is an autocycling and strand displacement DNA synthesis method. LAMP assays have been applied as a method of detecting a variety of animal pathogens, including BTV. RT- LAMP assay can be a valuable tool complementing the routine laboratory diagnosis of BTV.

scholarly journals Comparison of clinical and serological features of RT-PCR positive and negative COVID-19 patients

2021 ◽  
Vol 49 (2) ◽  
pp. 030006052097265
Author(s):  
Caiqin Li ◽  
Qi Su ◽  
Jun Liu ◽  
Lei Chen ◽  
Yuting Li ◽  
...  
Keyword(s):  
Symptom Onset ◽  
Retrospective Cohort ◽  
Time Window ◽  
Clinical Symptoms ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Serological Tests ◽  
Global Epidemic ◽  
Polymerase Chain ◽  
Demographic Features

Background In December 2019, an outbreak of coronavirus disease 2019 (COVID-19) began in Wuhan, China, and led to a global epidemic. We aimed to compare the clinical and serological features of COVID-19 patients with positive and negative reverse transcriptase polymerase chain reaction (RT-PCR) tests. Methods This was a retrospective cohort study conducted from 9 February to 4 April 2020. COVID-19 patients at Leishenshan Hospital in Wuhan, China (125 total cases; 87 RT-PCR positive and 38 RT-PCR negative) were included. COVID-19 serology was assessed by colloidal gold assay. All cases were analyzed for demographic, clinical, and serological features. Results There were no significant differences in most demographic features, clinical symptoms, complications or treatments of RT-PCR positive and negative COVID-19 patients. Serum IgM/IgG was positive in 82 (94%) and 33 (87%) RT-PCR positive and negative cases, respectively. IgM was detectable as early as 3 days after symptom onset and was undetectable 60 days after symptom onset. By contrast, IgG could be detected only 10 days after symptom onset and reached its peak 60 days after symptom onset. Conclusions Serological tests performed during the appropriate time window of disease progression could be valuable auxiliary methods to RT-PCR in COVID-19 patients.

scholarly journals Microbiological Laboratory Diagnosis of Human Brucellosis: An Overview

Pathogens ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1623
Author(s):  
Giovanni Di Bonaventura ◽  
Silvia Angeletti ◽  
Andrea Ianni ◽  
Tommasangelo Petitti ◽  
Giovanni Gherardi
Keyword(s):  
Clinical Symptoms ◽  
Early Stage ◽  
Point Of Care ◽  
Laboratory Diagnosis ◽  
Cross Reactivity ◽  
Diagnostic Methods ◽  
Nucleic Acid Amplification ◽  
Human Brucellosis ◽  
Microbiological Analysis ◽  
Serological Tests

Brucella spp. are Gram-negative, non-motile, non-spore-forming, slow-growing, facultative intracellular bacteria causing brucellosis. Brucellosis is an endemic of specific geographic areas and, although underreported, represents the most common zoonotic infection, with an annual global incidence of 500,000 cases among humans. Humans represent an occasional host where the infection is mainly caused by B. melitensis, which is the most virulent; B. abortus; B. suis; and B. canis. A microbiological analysis is crucial to identifying human cases because clinical symptoms of human brucellosis are variable and aspecific. The laboratory diagnosis is based on three different microbiological approaches: (i) direct diagnosis by culture, (ii) indirect diagnosis by serological tests, and (iii) direct rapid diagnosis by molecular PCR-based methods. Despite the established experience with serological tests and highly sensitive nucleic acid amplification tests (NAATs), a culture is still considered the “gold standard” in the laboratory diagnosis of brucellosis due to its clinical and epidemiological relevance. Moreover, the automated BC systems now available have increased the sensitivity of BCs and shortened the time to detection of Brucella species. The main limitations of serological tests are the lack of common interpretative criteria, the suboptimal specificity due to interspecies cross-reactivity, and the low sensitivity during the early stage of disease. Despite that, serological tests remain the main diagnostic tool, especially in endemic areas because they are inexpensive, user friendly, and have high negative predictive value. Promising serological tests based on new synthetic antigens have been recently developed together with novel point-of-care tests without the need for dedicated equipment and expertise. NAATs are rapid tests that can help diagnose brucellosis in a few hours with high sensitivity and specificity. Nevertheless, the interpretation of NAAT-positive results requires attention because it may not necessarily indicate an active infection but rather a low bacterial inoculum, DNA from dead bacteria, or a patient that has recovered. Refined NAATs should be developed, and their performances should be compared with those of commercial and home-made molecular tests before being commercialized for the diagnosis of brucellosis. Here, we review and report the most common and updated microbiological diagnostic methods currently available for the laboratory diagnosis of brucellosis.

scholarly journals Mass Antibody Detection: Can It be An Avenger for Infectivity War against COVID-19

2020 ◽  
Author(s):  
Sarfaraz Ahmad Ejazi ◽  
Sneha Ghosh ◽  
Nahid Ali
Keyword(s):  
Large Scale ◽  
Point Of Care ◽  
Cost Effective ◽  
Antibody Detection ◽  
Serological Tests ◽  
Ongoing Research ◽  
Molecular Tests ◽  
Immunological Assays ◽  
Commercial Kits ◽  
Vaccination Therapy

The ongoing pandemic of COVID-19 has not only commenced a global health emergency but agitated various aspects of humanity. During this period of crisis researchers over the world have ramped their efforts to constrain the disease in all possible ways whether it is vaccination, therapy, or diagnosis. Since the spread of the disease has not yet elapsed sharing the ongoing research findings could be the key to disease control and management. An early and efficient diagnosis could leverage the outcome until a successful vaccine is developed. Molecular tests both in-house and commercial kits are preferably being used worldwide in the COVID-19 diagnosis. However, the limitation of high prices and lengthy procedures impede their use for mass testing. Keeping the constant rise of infection in mind search for an alternative test that should be cost-effective, simple, and suitable for large scale testing and surveillance is a need of an hour. One such alternative could be the immunological tests. Therefore, in the last few months deluge of immunological rapid tests has been developed and validated across the globe. The objective of the present review is to share the diagnostic performance of various immunological assays reported so far in SARS-CoV-2 case detection. The article consolidated the studies (published and preprints) related to the serological tests such as chemiluminescence, enzyme-linked and lateral flow-based point-of-care tests in COVID-19 diagnosis and updated the current scenario. This review will hopefully be an add-on in COVID-19 research and will contribute to congregate the evidence for decision-making.

scholarly journals Diagnostic accuracy of a SARS-CoV-2 rapid test and optimal time for seropositivity according to the onset of symptoms

2022 ◽  
Vol 38 (1) ◽  
Author(s):  
Caroline Nespolo de David ◽  
Fernanda Hammes Varela ◽  
Ivaine Tais Sauthier Sartor ◽  
Márcia Polese-Bonatto ◽  
Ingrid Rodrigues Fernandes ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Sensitivity And Specificity ◽  
Clinical Symptoms ◽  
Point Of Care ◽  
Rapid Test ◽  
Lateral Flow Immunoassay ◽  
Optimal Time ◽  
Rt Pcr ◽  
Serological Tests ◽  
Over Time

Point-of-care serological tests for SARS-CoV-2 have been used for COVID-19 diagnosis. However, their accuracy over time regarding the onset of symptoms is not fully understood. We aimed to assess the accuracy of a point-of-care lateral flow immunoassay (LFI). Subjects, aged over 18 years, presenting clinical symptoms suggestive of acute SARS-CoV-2 infection were tested once by both nasopharyngeal and oropharyngeal RT-PCR and LFI. The accuracy of LFI was assessed in periodic intervals of three days in relation to the onset of symptoms. The optimal cut-off point was defined as the number of days required to achieve the best sensitivity and specificity. This cut-off point was also used to compare LFI accuracy according to participants’ status: outpatient or hospitalized. In total, 959 patients were included, 379 (39.52%) tested positive for SARS-CoV-2 with RT-PCR, and 272 (28.36%) tested positive with LFI. LFI best performance was achieved after 10 days of the onset of symptoms, with sensitivity and specificity of 84.9% (95%CI: 79.8-89.1) and 94.4% (95%CI: 91.0-96.8), respectively. Although the specificity was similar (94.6% vs. 88.9%, p = 0.051), the sensitivity was higher in hospitalized patients than in outpatients (91.7% vs. 82.1%, p = 0.032) after 10 days of the onset of symptoms. Best sensitivity of point-of-care LFI was found 10 days after the onset of symptoms which may limit its use in acute care. Specificity remained high regardless of the number of days since the onset of symptoms.

scholarly journals Screening, Diagnostic and Prognostic Tests for COVID-19: A Comprehensive Review

Life ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 561
Author(s):  
Mariana Ulinici ◽  
Serghei Covantev ◽  
James Wingfield-Digby ◽  
Apostolos Beloukas ◽  
Alexander G. Mathioudakis ◽  
...  
Keyword(s):  
Point Of Care ◽  
Standard Test ◽  
Current Evidence ◽  
Molecular Testing ◽  
Rt Pcr ◽  
Diagnostic Screening ◽  
Comprehensive Review ◽  
Prognostic Tests ◽  
Polymerase Chain ◽  
Antigen Testing

While molecular testing with real-time polymerase chain reaction (RT-PCR) remains the gold-standard test for COVID-19 diagnosis and screening, more rapid or affordable molecular and antigen testing options have been developed. More affordable, point-of-care antigen testing, despite being less sensitive compared to molecular assays, might be preferable for wider screening initiatives. Simple laboratory, imaging and clinical parameters could facilitate prognostication and triage. This comprehensive review summarises current evidence on the diagnostic, screening and prognostic tests for COVID-19.

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