The usefulness of antigen testing in predicting contagiousness in COVID-19

Increasing the diagnostic capacity of COVID-19 (SARS-CoV-2 infection) is required to improve case detection, reduce COVID-19 expansion, and boost the world economy. Rapid antigen detection tests are cheaper and easier to implement, but their diagnostic performance has been questioned compared to RT-PCR. Here, we evaluate the performance of the Standard Q COVID-19 antigen test for diagnosing SARS-CoV-2 infection and predicting contagiousness compared to RT-PCR and viral culture, respectively. The antigen test was 100.0% specific but only 40.9% sensitive for diagnosing infection compared to RT-PCR. Interestingly, SARS-CoV-2 contagiousness is highly unlikely with a negative antigen test since it exhibited a negative predictive value of 99.9% than viral culture. Furthermore, a cycle threshold (Ct) value of 18.1 in RT-PCR was shown to be the one that best predicts contagiousness (AUC 97.6%). Thus, screening people with antigen testing is a good approach to prevent SARS-CoV-2 contagion and allow returning to daily activities.

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CRYPTOCURRENCY PHENOMENON IN THE INTERNATIONAL MONETARY SYSTEM

ЕКОНОМІКА І РЕГІОН Науковий вісник ◽

10.26906/eir.2017.3(64).882 ◽

2017 ◽

pp. 95-100

Author(s):

Артур Анатолійович Василенко

Keyword(s):

World Economy ◽

International Monetary System ◽

State University ◽

Electronic Money ◽

Monetary System ◽

Current Trends ◽

The World ◽

Post Graduate Student ◽

The One ◽

Xix Century

UDC 336.74 Vasylenko Artur, post-graduate student. Mariupol State University. Cryptocurrency Phenomenon in the International Monetary System. The main prerequisites of cryptocurrency emergence in the international monetary system in terms of regionalization of the world economy are defined in the article. Determination of «cryptocurrency» category was analysed from the point of two main approaches to its treatment: on the one hand cryptocurrency is admitted to be the currency equally to the sovereign currency, and on the other hand it is considered as an unrecognized virtual asset. The main consequences which arise in case of widespread use of crypto currency for the country and for the parties that agreed to use cryptocurrency were analysed and systematized. On the basis of the research, given the current trends in the world economy, the author put forward and substantiated the hypothesis to classify the phenomenon of cryptocurrency as the effects of a famous philosophical «Negation of negation law» formulated by G. Hegel at the beginning of the XIX century. Keywords: cryptocurrency, material money, electronic money, digital currency, regional currency integration, blockchain, mining, capitalization, «Negation of negation law».

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Structural changes and economic growth in the world economy and Russia

Russian Journal of Economics ◽

10.32609/j.ruje.5.35233 ◽

2019 ◽

Vol 5 (1) ◽

pp. 1-26 ◽

Cited By ~ 1

Author(s):

Valeriy V. Mironov ◽

Liudmila D. Konovalova

Keyword(s):

Economic Growth ◽

Growth Rate ◽

Global Economy ◽

World Economy ◽

Structural Changes ◽

Russian Economy ◽

The World ◽

Preliminary Version ◽

The One ◽

Relationship Of

The article considers the problem of the relationship of structural changes and economic growth in the global economy and Russia in the framework of different methodological approaches. At the same time, the paper provides the analysis of complementarity of economic policy types, which, on the one hand, are aimed at developing the fundamentals of GDP growth (institutions, human capital and macroeconomic stabilization), and on the other hand, at initiating growth (with stable fundamentals) with the help of structural policy measures. In the study of structural changes in the global economy, new forms of policies of this kind have been revealed, in particular aimed at identifying sectors — drivers of economic growth based on a portfolio approach. In a given paper a preliminary version of the model of the Russian economy is provided, using a multisector version of the Thirlwall’s Law. Besides, the authors highlight a number of target parameters of indicators of competitiveness of the sectors of the Russian economy that allow us to expect its growth rate to accelerate above the exogenously given growth rate of the world economy.

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Impact of Covid-19 on Business Industry and Management: Pandemic Challenges and Responses

Prastuti: Journal of Management & Research ◽

10.51976/gla.prastuti.v9i2.922007 ◽

2021 ◽

Vol 9 (2) ◽

Keyword(s):

Problem Solving ◽

Impact Assessment ◽

Business Process ◽

World Economy ◽

Business Management ◽

The Other ◽

Problem Structure ◽

Global Business ◽

The World ◽

The One

Covid-19 pandemic has created unprecedented interruption for the global business industry management. The world economy already facing a turbulent phase experienced the worst scenario in the view of this pandemic. Business management strategists and policymakers have been making an impact assessment to understand the problem structure of this worst possible pandemic situation. The present article tries to develop a viewpoint on Covid-19 impact on business industries and management. Further authors attempt to develop a problem-solving structure by discussing the best possible solutions to mitigate the fact on the one hand and facilitating the business process in various sectors such as business Industry, Marketing, finance, and health industries on the other.

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Comparison of SARS-CoV-2 antigen electrochemiluminescence immunoassay to RT-PCR assay for laboratory diagnosis of COVID-19 in Peshawar

Diagnosis ◽

10.1515/dx-2021-0078 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Bilal Iqbal ◽

Maria Khan ◽

Noman Shah ◽

Mirza Muhammad Dawood ◽

Valeed Jehanzeb ◽

...

Keyword(s):

Laboratory Diagnosis ◽

Cross Sectional Study ◽

Antigen Test ◽

Rt Pcr ◽

Pcr Assay ◽

Cross Sectional ◽

Viral Loads ◽

Testing Algorithms ◽

Frequent Testing ◽

Antigen Testing

Abstract Objectives Antigen based rapid diagnostic tests possesses a potential to be utilized along with Gold standard methods to detect Covid-19 infection to cope with the demand of testing. The aim of this study was to determine diagnostic accuracy of electrochemiluminescence based automated antigen detection immunoassay comparing with molecular based test RT-PCR (Covid-19). Methods It was a cross-sectional study conducted in RMI Peshawar, from 1st April 2021 till 30th April 2021. The study comprised 170 individuals who were suspected of having Covid-19. Nasopharyngeal samples taken from suspected individuals were analyzed by RT-PCR and automated antigen test (Elecsys SARS-CoV-2 Antigen) simultaneously. The correlation of SARS-CoV-2 antigen with PCR positive and negative cases was analyzed for specificity, sensitivity respectively. Results The ECLIA based Elecsys antigen test (Roche) revealed overall sensitivity 72%, specificity 95% and accuracy of 94.9%. Sensitivity of antigen test progressively declined from 94.3% in Ct <25 to 70.8% in Ct 26–29 and then to 47.2% in Ct 30–35. Conclusions Based on the findings of our study we conclude that automated antigen testing (Elecsys SARS-CoV-2 Antigen) cannot replace molecular based testing like RT PCR. Elecsys SARS-CoV-2 Ag test should be used complementary to RT-PCR in testing algorithms. Frequent testing strategy should be adopted while using automated antigen testing to overcome its limitation in individuals with low viral loads.

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Angola - an Oil Dependant Country in Sub-Saharan Africa

Studia commercialia Bratislavensia ◽

10.1515/stcb-2016-0023 ◽

2016 ◽

Vol 9 (35) ◽

pp. 233-242

Author(s):

Boris Baumgartner

Keyword(s):

South Africa ◽

World Economy ◽

Sub Saharan Africa ◽

African Countries ◽

The Third ◽

The World ◽

Sub Saharan ◽

The One ◽

Rich Countries ◽

Essential Problem

Abstract The Sub-Saharan Africa belongs to the most underdeveloped regions in the world economy. This region consists of forty nine countries but it’s world GDP share is only a small percentage. There are some very resource rich countries in this region. One of them is Angola. This former Portuguese colony has one of the largest inventories of oil among all African countries. Angola recorded one of the highest growth of GDP between 2004-2008 from all countries in the world economy and nowadays is the third biggest economy in Sub-Saharan Africa after Nigeria and South Africa. The essential problem of Angola is the one-way oriented economy on oil and general on natural resources. Angola will be forced to change their one-way oriented economy to be more diversified and competitive in the future.

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The International Anti-Offshore Regulation in the Context of Global Financial Imbalances

Business Inform ◽

10.32983/2222-4459-2020-12-60-65 ◽

2020 ◽

Vol 12 (515) ◽

pp. 60-65

Author(s):

A. V. Maksymenko ◽

Keyword(s):

Tax Evasion ◽

World Economy ◽

Driving Forces ◽

Stage Of Development ◽

The World ◽

Need To Evaluate ◽

Financial Infrastructure ◽

Vector Orientation ◽

The One ◽

And Control

At the present stage of development of the world economy, problems of capital migration in offshore zones began to manifest in relief, which adversely affects the state of the global financial system. These trends lead to the need to evaluate new directions of the anti-offshore regulation. It is proved that the transformation of the anti-offshore regulation by its nature, driving forces, vector orientation and mechanism of development at all stages of the world-economy progress clearly reflects the systemic transformations of global financial imbalances. It is found out that the evaluation of offshore jurisdictions comes out of the degree of transparency of their activities, as well as readiness to cooperate on the exchange of tax information within the framework of the OECD’s special concept of mutual assistance in tax affairs. The role of international organizations in regulating anti-offshore activities has been identified, and the prospects for their influence have been evaluated. It is determined that the anti-offshore regulation is implemented, on the one hand, through shifting of emphasis from combating the fiscal benefits of offshore zones to limit activities with the «black» (tax-free) zones, and on the other hand – through the mechanisms of international economic policy implemented on the institutional platform of international currency together with the credit and financial organizations. The author describe preventive measures on tax evasion, which consist in the development of an inclusive structure of the OECD and G20, which will allow interested countries and jurisdictions to cooperate in the development of standards on issues related to tax evasion, as well as with supervision and control over the implementation of the entire package of actions. It is determined that the mechanism of de-offshoring should be directed not only towards the elimination of territories with preferential taxation, but also towards benefits from their use on the basis of the existing financial infrastructure of the world’s leading offshore centers.

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Direct Comparison of SARS Co-V-2 Nasal RT- PCR and Rapid Antigen Test (BinaxNOWTM) at a Community Testing Site During an Omicron Surge

10.1101/2022.01.08.22268954 ◽

2022 ◽

Author(s):

John Schrom ◽

Carina Marquez ◽

Genay Pilarowski ◽

Grace Wang ◽

Anthea Mitchell ◽

...

Keyword(s):

San Francisco ◽

High Viral Load ◽

Antigen Test ◽

Rt Pcr ◽

Repeat Testing ◽

Single Antigen ◽

Testing Site ◽

Antigen Testing ◽

Test Result ◽

Community Site

In 731 persons seeking COVID-19 testing at a walk-up San Francisco community site in January 2022, simultaneous nasal rapid antigen testing (BinaxNOWTM) and RT-PCR testing was performed. There were 296 (40.5%) positive tests by RT-PCR; 97% of a random sample were the omicron variant. Sensitivity of a single antigen test was 95.2% (95% CI 92-98%); 82.1% (95% CI 77-87%) and 65.2% (95% CI 60-70%) for Ct threshold of < 30, < 35 and no threshold, respectively. A single BinaxNowTM rapid antigen test detected 95% of high viral load omicron cases from nasal specimens. As currently recommended, repeat testing should be done for high- risk persons with an initial negative antigen test result.

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Diagnostic performance of a novel digital immunoassay (RapidTesta SARS-CoV-2): a prospective observational study with 1,127 nasopharyngeal samples

10.1101/2021.07.26.21261162 ◽

2021 ◽

Author(s):

Hiromichi Suzuki ◽

Yusaku Akashi ◽

Atsuo Ueda ◽

Yoshihiko Kiyasu ◽

Yuto Takeuchi ◽

...

Keyword(s):

Diagnostic Performance ◽

Prospective Observational Study ◽

Test Results ◽

Antigen Test ◽

Rt Pcr ◽

Asymptomatic Patients ◽

Pcr Method ◽

Antigen Tests ◽

Positive Line ◽

Test Cassette

Introduction: Digital immunoassays are generally regarded as superior tests for the detection of infectious disease pathogens, but there have been insufficient data concerning SARS-CoV-2 immunoassays. Methods: We prospectively evaluated a novel digital immunoassay (RapidTesta SARS-CoV-2). Two nasopharyngeal samples were simultaneously collected for antigen tests and RT-PCR. Real-time RT-PCR for SARS-CoV-2, using a method developed by the National Institute of Infectious Diseases, Japan, served as the reference RT-PCR method. Results: During the study period, 1,127 nasopharyngeal samples (symptomatic patients: 802, asymptomatic patients: 325) were evaluated. For digital immunoassay antigen tests, the sensitivity was 78.3% (95% CI: 67.3%-87.1%) and the specificity was 97.6% (95% CI: 96.5%-98.5%). When technicians visually analyzed the antigen test results, the sensitivity was 71.6% (95% CI: 59.9%-81.5%) and the specificity was 99.2% (95% CI: 98.5%-99.7%). Among symptomatic patients, the sensitivity was 89.4% (95% CI; 76.9%-96.5%) with digital immunoassay antigen tests, and 85.1% (95% CI; 71.7%-93.8%) with visually analyzed the antigen test, respectively. Conclusions: The findings indicated that RapidTesta SARS-CoV-2 analysis with the DIA device had sufficient analytical performance for the detection of SARS-CoV-2 in nasopharyngeal samples. When positive DIA results are recorded without a visually recognizable red line at the positive line location on the test cassette, additional RT-PCR evaluation should be performed.

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On the role of transnational corporations in modern integration and globalization processes

Russian Economic Journal ◽

10.33983/0130-9757-2019-3-97-106 ◽

2019 ◽

pp. 97-106

Author(s):

P.Yu. Baryshnikov

Keyword(s):

World Economy ◽

Transnational Corporations ◽

Negative Consequences ◽

Host Countries ◽

The World ◽

New Type ◽

The One ◽

The Impact ◽

The Relationship

The subject of the author's research is the development of transnational corporations (TNCs) as an organic component of modern international economic integration and globalization processes. The concept and features of TNCs are characterized. A brief historical overview of the formation and development of corporate transnationalism is proposed. Statistics on the largest TNCs are presented and analyzed. On the one hand, positive aspects of the impact of TNCs on the development of the world economy and its national components were identified, and on the other hand, the negative consequences of the expansion of these corporations for both host countries and home countries of TNCs. The relationship between TNCs and sovereign States is considered in many aspects. Thus, based on the analysis of the instruments of influence of the companies under consideration on the normative activities of the States, a shift from the interstate to the corporate legal field was recorded. One of the subjects of the article is mega regional trade agreements of a new type as a factor of increasing the contradictory impact of TNCs on the development of the world economy and its national components.

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Failure of Routine Diagnostic Methods to Detect Influenza in Hospitalized Older Adults

Infection Control and Hospital Epidemiology ◽

10.1086/653202 ◽

2010 ◽

Vol 31 (7) ◽

pp. 683-688 ◽

Cited By ~ 27

Author(s):

H. Keipp Talbot ◽

John V. Williams ◽

Yuwei Zhu ◽

Katherine A. Poehling ◽

Marie R. Griffin ◽

...

Keyword(s):

Confidence Interval ◽

Hospital Setting ◽

Respiratory Illness ◽

Diagnostic Methods ◽

Antigen Test ◽

Rt Pcr ◽

Influenza Like Illness ◽

Viral Culture ◽

Hospitalized Older Adults ◽

Definition Of

Objective.To define the utility of using routine diagnostic methods to detect influenza in older, hospitalized adults.Design.Descriptive study.Setting.One academic hospital and 1 community hospital during the 2006–2007 and 2007–2008 influenza seasons.Participants.Hospitalized adults 50 years of age or older.Methods.Adults who were 50 years of age or older and hospitalized with symptoms of respiratory illness were enrolled and tested for influenza by use of reverse-transcriptase polymerase chain reaction (RT-PCR). Using RT-PCR as the gold standard, we assessed the performances of rapid antigen tests and conventional influenza culture and the diagnostic use of the clinical definition of influenza-like illness.Results.Influenza was detected by use of RT-PCR in 26 (11%) of 228 patients enrolled in our study. The sensitivity of the rapid antigen test performed at bedside by research staff members was 19.2% (95% confidence interval, 8.51%–37.9%); the sensitivity of conventional influenza culture was 34.6% (95% confidence interval, 19.4%–53.8%). The ability to detect influenza with both the rapid antigen test and culture was associated with patients with a higher viral load (P= .002 andP= .001, respectively). The ability to diagnose influenza by use of the clinical definition of influenza-like illness had a higher sensitivity (80.8%) but lacked specificity (40.6%).Conclusion.Because rapid antigen testing and viral culture have poor sensitivity (19.2% and 34.6%, respectively), neither testing method is sufficient to use to determine what type of isolation procedures to implement in a hospital setting.

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