scholarly journals Are we there yet? An adaptive SIR model for continuous estimation of COVID-19 infection rate and reproduction number in the United States (Preprint)

2020 ◽  
Author(s):  
Mark Shapiro ◽  
Fazle Karim ◽  
Guido Muscioni ◽  
Abel Saju Augustine
Keyword(s):  
Infection Rate ◽  
Reproduction Number ◽  
Infected Individual ◽  
Local Population ◽  
The United States ◽  
Mitigation Measures ◽  
Simple Method ◽  
Wide Range ◽  
Continuous Estimation ◽  
The Impact

BACKGROUND The dynamics of the COVID-19 epidemic vary due to local population density and policy measures. When making decisions, policy makers consider an estimate of the effective reproduction number R_t which is the expected number of secondary infections by a single infected individual. OBJECTIVE We propose a simple method for estimating the time-varying infection rate and reproduction number R_t . METHODS We use a sliding window approach applied to a Susceptible-Infectious-Removed model. The infection rate is estimated using the reported cases for a seven-day window to obtain continuous estimation of R_t. The proposed adaptive SIR (aSIR) model was applied to data at the state and county levels. RESULTS The aSIR model showed an excellent fit for the number of reported COVID-19 positive cases, a one-day forecast MAPE was less than 2.6% across all states. However, a seven-day forecast MAPE reached 16.2% and strongly overestimated the number of cases when the reproduction number was high and changing fast. The maximal R_t showed a wide range of 2.0 to 4.5 across all states, with the highest values for New York (4.4) and Michigan (4.5). We demonstrate that the aSIR model can quickly adapt to an increase in the number of tests and associated increase in the reported cases of infections. Our results also suggest that intensive testing may be one of the effective methods of reducing R_t. CONCLUSIONS The aSIR model provides a simple and accurate computational tool to obtain continuous estimation of the reproduction number and evaluate the impact of mitigation measures.

scholarly journals Are we there yet? An adaptive SIR model for continuous estimation of COVID-19 infection rate and reproduction number in the United States

2020 ◽  
Author(s):  
Mark B Shapiro ◽  
Fazle Karim ◽  
Guido Muscioni ◽  
Abel Saju Augustine
Keyword(s):  
New York ◽  
Infection Rate ◽  
Reproduction Number ◽  
Infected Individual ◽  
Local Population ◽  
The United States ◽  
Mitigation Measures ◽  
Simple Method ◽  
Wide Range ◽  
Continuous Estimation

AbstractBackgroundThe dynamics of the COVID-19 epidemic vary due to local population density and policy measures. When making decisions, policy makers consider an estimate of the effective reproduction number ℛt which is the expected number of secondary infections by a single infected individual.ObjectiveWe propose a simple method for estimating the time-varying infection rate and reproduction number ℛt.MethodsWe use a sliding window approach applied to a Susceptible-Infectious-Removed model. The infection rate is estimated using the reported cases for a seven-day window to obtain continuous estimation of ℛt. The proposed adaptive SIR (aSIR) model was applied to data at the state and county levels.ResultsThe aSIR model showed an excellent fit for the number of reported COVID-19 positive cases, a one-day forecast MAPE was less than 2.6% across all states. However, a seven-day forecast MAPE reached 16.2% and strongly overestimated the number of cases when the reproduction number was high and changing fast. The maximal ℛt showed a wide range of 2.0 to 4.5 across all states, with the highest values for New York (4.4) and Michigan (4.5). We demonstrate that the aSIR model can quickly adapt to an increase in the number of tests and associated increase in the reported cases of infections. Our results also suggest that intensive testing may be one of the effective methods of reducing ℛt.ConclusionThe aSIR model provides a simple and accurate computational tool to obtain continuous estimation of the reproduction number and evaluate the efficacy of mitigation measures.

scholarly journals Trajectory of individual immunity and vaccination required for SARS-CoV-2 community immunity: a conceptual investigation

2021 ◽  
Vol 18 (175) ◽  
pp. 20200683
Author(s):  
Chadi M. Saad-Roy ◽  
Simon A. Levin ◽  
C. Jessica E. Metcalf ◽  
Bryan T. Grenfell
Keyword(s):  
Reproduction Number ◽  
Infected Individual ◽  
Mitigation Measures ◽  
Simple Description ◽  
Vaccination Rates ◽  
Epidemic Dynamics ◽  
Low Levels ◽  
Analytical Relations ◽  
The Impact ◽  
Individual Immunity

SARS-CoV-2 is an international public health emergency; high transmissibility and morbidity and mortality can result in the virus overwhelming health systems. Combinations of social distancing, and test, trace, and isolate strategies can reduce the number of new infections per infected individual below 1, thus driving declines in case numbers, but may be both challenging and costly. These interventions must also be maintained until development and (now likely) mass deployment of a vaccine (or therapeutics), since otherwise, many susceptible individuals are still at risk of infection. We use a simple analytical model to explore how low levels of infection, combined with vaccination, determine the trajectory to community immunity. Understanding the repercussions of the biological characteristics of the viral life cycle in this scenario is of considerable importance. We provide a simple description of this process by modelling the scenario where the effective reproduction number R eff is maintained at 1. Since the additional complexity imposed by the strength and duration of transmission-blocking immunity is not yet clear, we use our framework to probe the impact of these uncertainties. Through intuitive analytical relations, we explore how the necessary magnitude of vaccination rates and mitigation efforts depends crucially on the durations of natural and vaccinal immunity. We also show that our framework can encompass seasonality or preexisting immunity due to epidemic dynamics prior to strong mitigation measures. Taken together, our simple conceptual model illustrates the importance of individual and vaccinal immunity for community immunity, and that the quantification of individuals immunized against SARS-CoV-2 is paramount.

scholarly journals Mining Google and Apple mobility data: temporal anatomy for COVID-19 social distancing

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Corentin Cot ◽  
Giacomo Cacciapaglia ◽  
Francesco Sannino
Keyword(s):  
Infection Rate ◽  
The United States ◽  
Strong Decrease ◽  
Social Distancing ◽  
Mobility Data ◽  
Actual Measure ◽  
The Us ◽  
The Impact ◽  
Political Decisions ◽  
Mobility Reduction

AbstractWe employ the Google and Apple mobility data to identify, quantify and classify different degrees of social distancing and characterise their imprint on the first wave of the COVID-19 pandemic in Europe and in the United States. We identify the period of enacted social distancing via Google and Apple data, independently from the political decisions. Our analysis allows us to classify different shades of social distancing measures for the first wave of the pandemic. We observe a strong decrease in the infection rate occurring two to five weeks after the onset of mobility reduction. A universal time scale emerges, after which social distancing shows its impact. We further provide an actual measure of the impact of social distancing for each region, showing that the effect amounts to a reduction by 20–40% in the infection rate in Europe and 30–70% in the US.

scholarly journals The Effect of Vaccination Rates on the Infection of COVID-19 under the Vaccination Rate below the Herd Immunity Threshold

2021 ◽  
Vol 18 (14) ◽  
pp. 7491
Author(s):  
Yi-Tui Chen
Keyword(s):  
Infection Rate ◽  
Herd Immunity ◽  
The United States ◽  
Vaccination Rate ◽  
Infection Rates ◽  
Vaccination Rates ◽  
The United Kingdom ◽  
The World ◽  
Almost All ◽  
The Impact

Although vaccination is carried out worldwide, the vaccination rate varies greatly. As of 24 May 2021, in some countries, the proportion of the population fully vaccinated against COVID-19 has exceeded 50%, but in many countries, this proportion is still very low, less than 1%. This article aims to explore the impact of vaccination on the spread of the COVID-19 pandemic. As the herd immunity of almost all countries in the world has not been reached, several countries were selected as sample cases by employing the following criteria: more than 60 vaccine doses per 100 people and a population of more than one million people. In the end, a total of eight countries/regions were selected, including Israel, the UAE, Chile, the United Kingdom, the United States, Hungary, and Qatar. The results find that vaccination has a major impact on reducing infection rates in all countries. However, the infection rate after vaccination showed two trends. One is an inverted U-shaped trend, and the other is an L-shaped trend. For those countries with an inverted U-shaped trend, the infection rate begins to decline when the vaccination rate reaches 1.46–50.91 doses per 100 people.

Assessing the Preparedness of Healthcare Facilities for Disasters and Emergencies in Damghan, Iran

2021 ◽  
pp. 1-7
Author(s):  
Behrad Pourmohammadi ◽  
Ahad Heydari ◽  
Farin Fatemi ◽  
Ali Modarresi
Keyword(s):  
Health Care ◽  
Cross Sectional Study ◽  
Health Care Facilities ◽  
Mitigation Measures ◽  
Health Staff ◽  
Cross Sectional ◽  
Healthcare Facilities ◽  
Wide Range ◽  
Care Facilities ◽  
The Impact

Abstract Objectives: Iran is exposed to a wide range of natural and man-made hazards. Health-care facilities can play a significant role in providing life-saving measures in the minutes and hours immediately following the impact or exposure. The aim of this study was to determine the preparedness of health-care facilities in disasters and emergencies. Methods: This cross-sectional study was conducted in Damghan, Semnan Province, in 2019. The samples consisted of all the 11 health-care facilities located in Damghan County. A developed checklist was used to collect the data, including 272 questions in 4 sections: understanding threatening hazards, functional, structural, and nonstructural vulnerability of health-care facilities. The data were analyzed using SPSS 21. Results: The results revealed that the health-care facilities were exposed to 22 different natural and man-made hazards throughout the county. The total level of preparedness of the health-care centers under assessment was 45.8%. The average functional, structural, and nonstructural vulnerability was assessed at 49.3%, 31.6%, and 56.4%, respectively. Conclusions: Conducting mitigation measures is necessary for promoting the functional and structural preparedness. Disaster educational programs and exercises are recommended among the health staff in health-care facilities.

A New World Economic order formation

2021 ◽  
pp. 932-950
Author(s):  
Vladislav Vyacheslavovich Emelyanov
Keyword(s):  
Oil And Gas ◽  
World Order ◽  
The United States ◽  
New Order ◽  
The West ◽  
Wide Range ◽  
The World ◽  
The Usa ◽  
World Economic Order ◽  
The Impact

Every few decades, the world order changes due to various geopolitical, economic and other circumstances. For example, as a result of globalization, the world order has undergone significant changes in the last forty years. Globalization has led to the destruction of the postwar world order, as well as to world leadership by the United States and the West. However, in recent decades, as a result of globalization, the U.S. and the West began to cede their leadership to developing countries, so there is now a change in the economic structure of relations in the world system. Today the center of economic growth is in the East, namely in Asia. There are no new superpowers in the world at the moment, but the unipolar world will cease to exist due to the weakening of the U. S. leadership, which will lead to a change in the world order. A new leader, which may replace the U. S., will not have as wide range of advantages as the USA has. Most likely, the essence of the new order will be to unite the largest countries and alliances into blocks, for example, the USA together with the Trans-Pacific Partnership, the EU, etc. The article outlines forecasts of GDP growth rates as well as the global energy outlook; analyzes the LNG market as well as the impact of the pandemic on the global oil and gas market; and lists the characteristics of U. S. geopolitics.

scholarly journals Quebec’s Economic and Commercial Linkages with the United States, 1994–2017

2017 ◽  
Author(s):  
Earl H. Fry
Keyword(s):  
United States ◽  
Trade Agreement ◽  
The United States ◽  
The North ◽  
Nation States ◽  
Wide Range ◽  
The Us ◽  
Us Government ◽  
Big Picture ◽  
The Impact

This article examines the ebb and flow of the Quebec government’s economic and commercial relations with the United States in the period 1994–2017. The topic demonstrates the impact of three major forces on Quebec’s economic and commercial ties with the US: (1) the North American Free Trade Agreement (NAFTA) which became operational in 1994 and was fully implemented over a 15-year period; (2) the onerous security policies put in place by the US government in the decade following the horrific events of 11 September 2001; and (3) changing economic circumstances in the United States ranging from robust growth to the worst recession since the Great Depression of the 1930s. The article also indicates that the Quebec government continues to sponsor a wide range of activities in the United States, often more elaborate and extensive than comparable activities pursued by many nation-states with representation in the US. 1 1 Stéphane Paquin, ‘Quebec-U.S. Relations: The Big Picture’, American Review of Canadian Studies 46, no. 2 (2016): 149–61.

scholarly journals Living and Teaching Internationally: Teachers Talk about Personal Experiences, Benefits, and Challenges

2020 ◽  
Vol 19 (1) ◽  
pp. 38-53
Author(s):  
Nelly Sierra Ospina ◽  
Sergio Lopera Medina
Keyword(s):  
Classroom Management ◽  
Cultural Awareness ◽  
School Administrators ◽  
The United States ◽  
Structured Interview ◽  
Study Data ◽  
Intercultural Development ◽  
Life Styles ◽  
Wide Range ◽  
The Impact

This study reports on the impact of international visiting faculty’s teaching experiences in the United States on their personal, professional, and intercultural development. It is based on the principles of qualitative research and can be described as a case study. Data collection involved a questionnaire, a written narrative, and a semi-structured interview with each of a number of teachers. Participants included a group of 22 visiting faculty. Three main categories, each of which can be subdivided into benefits and challenges, emerged from the analysis: intercultural matters, professional matters, and personal matters. A wide range of benefits was identified, suggesting that the participants adapted to new life styles, became more mature, obtained a deeper understanding of themselves, reaffirmed their own educational values and philosophies, raised cultural awareness, became more flexible, and developed attitudes that involved tolerance and respect. Conversely, visiting faculty reported that they faced challenges related to language barriers, interaction with native speakers, classroom management, lack of support from school administrators, and separation from family.

Assessment in American Higher Education: The Role of Admissions Tests

2019 ◽  
Vol 683 (1) ◽  
pp. 130-148 ◽  
Author(s):  
Rebecca Zwick
Keyword(s):  
Higher Education ◽  
United States ◽  
The United States ◽  
College Performance ◽  
Admissions Tests ◽  
Higher Education System ◽  
Wide Range ◽  
Test Optional ◽  
The Impact

In this article, I review the role of college admissions tests in the United States and consider the fairness issues surrounding their use. The two main tests are the SAT, first administered in 1926, and the ACT, first given in 1959. Scores on these tests have been shown to contribute to the prediction of college performance, but their role in the admissions process varies widely across colleges. Although test scores are consistently listed as one of the most important admissions factors in national surveys of postsecondary institutions, an increasing number of schools have adopted “test-optional” policies. At these institutions, test score requirements are seen as a barrier to campus diversity because of the large performance gaps among ethnic and socioeconomic groups. Fortunately, the decentralized higher education system in the United States can accommodate a wide range of admissions policies. It is essential, however, that the impact of admissions policy changes be studied and that the resource implications of these changes be thoroughly considered.

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