Corpus overview


Overview

MeSH Disease

Human Phenotype

Transmission

Seroprevalence
    displaying 521 - 530 records in total 940
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    Analysis of the SARS-CoV-2 Outbreak in Northern Cyprus using a Mathematical Model

    Authors: Tamer Sanlidag; Nazife Sultanoglu; Bilgen Kaymakamzade; Evren Hincal; Murat Sayan; Kaya Suer; Buket Baddal

    doi:10.21203/rs.3.rs-28704/v1 Date: 2020-05-13 Source: ResearchSquare

    The present study studied the dynamics of SARS-CoV-2 in Northern-Cyprus (NC) by using real data and a designed mathematical model. The model consisted of two equilibrium points, which were disease-free and epidemic. The stability of the equilibrium points was determined by the magnitude of the basic reproduction number TRANS (π‘ΉπŸŽ). If π‘ΉπŸŽ < 1, the disease eventually disappears, if π‘ΉπŸŽ β‰₯ 1, the presence of an epidemic is stated. π‘ΉπŸŽ has been calculated patient zero, with a range of 2.38 to 0.65. Currently, the π‘ΉπŸŽ for NC was found to be 0.65, indicating that NC is free from the SARS-CoV-2 epidemic. MESHD

    The real time effective reproductive number TRANS for COVID-19 in the United States

    Authors: Yue Zhang; Lindsay T Keegan; Qiu Yuqing; Matthew H Samore

    doi:10.1101/2020.05.08.20095703 Date: 2020-05-13 Source: medRxiv

    none.

    Mathematical model of COVID-19 spread in Turkey and South Africa

    Authors: Abdon ATANGANA; Seda IGRET ARAZ

    doi:10.1101/2020.05.08.20095588 Date: 2020-05-13 Source: medRxiv

    A comprehensive study about the spread of COVID-19 cases in Turkey and South Africa has been presented in this paper . An exhaustive statistical analysis encompassing arithmetic, geometric, harmonic means, standard deviation, skewness, variance, Pearson and Spearman correlation was derived from the data collected from Turkey and South Africa within the period of 11 March 2020 to 3 May 2020 and 05 March and 3 of May respectively. It was observed that in the case of Turkey, a negative Spearman correlation for the number of infected class and a positive Spearman correlation for both the number of deaths MESHD and recoveries were obtained. This implied that the daily infections could decrease, while the daily deaths MESHD and number of recovered people could increase under current conditions. In the case of South Africa, a negative Spearman correlation for both daily deaths MESHD and daily infected people was obtained, indicating that these numbers may decrease if the current conditions are maintained. The utilization of a statistical technique predicted the daily number of infected, recovered and dead people for each country; and three results were obtained for Turkey, namely an upper boundary, a prediction from current situation and lower boundary. The prediction shows that Turkey may register in the near future approximately more than 6000 new infections in a day as worst case scenario; and less than 300 cases in the perfect scenario. However, the country could register in the near future a daily number of 27000 people recovered from COVID-19 in the perfect scenario; and less than 5000 people in a worst scenario. Moreover, Turkey in a worst-case scenario could record a high number of approximately 200 deaths per day; and less than 150 deaths in a perfect scenario. Similarly, in the case of South Africa, the prediction results show that in the near future the country could register about 500 new infected cases daily and more than 25 deaths in the worst scenario; while in a perfect scenario less than 50 new infected and zero death MESHD cases could be recorded. The histograms of the daily number of newly infected, recovered and death showed a sign of lognormal and normal distribution, which is presented using the Bell curving method parameters estimation. A new mathematical model COVID-19 comprised of nine classes was suggested; of which a formula of the reproductive number TRANS, well-poseness of the solutions and the stability analysis were presented in details. The suggested model was further extended to the scope of nonlocal operators for each case; whereby the Atangana-Seda numerical method was used to provide numerical solutions, and simulations were performed for different non-integer numbers. Additionally, sections devoted to control optimal and others dedicated to compare cases between Turkey and South Africa with the aim to comprehend why there are less numbers of deaths and infected people MESHD in South Africa than Turkey were presented in details.

    Evolving Epidemiology and Effect of Non-pharmaceutical Interventions on the Epidemic of Coronavirus Disease MESHD 2019 in Shenzhen, China

    Authors: Suli Huang; Zhen Zhang; Yongsheng Wu; Shujiang Mei; Yuan Li; Xu Xie; Xiaojian Liu; Xiujuan Tang; Dongfeng Kong; Xiaoliang Wu; Yu Wu; Lan Wei; Ziquan Lv; Shuyuan Yu; Ying Wen; Guohong Zhou; Tianmu Chen; Tiejian Feng; Xuan Zou

    doi:10.1101/2020.05.09.20084202 Date: 2020-05-13 Source: medRxiv

    Previous studies have demonstrated the characteristics of patients with 2019 novel coronavirus disease MESHD (COVID-19). However, the effect of non-pharmaceutical interventions on the epidemic in Shenzhen, China remains unknown. Individual data of 417 cases were extracted from the epidemiological investigations and the National Infectious Disease MESHD Information System between January 1, 2020 and February 29, 2020. On the basis of important interventions, the epidemic was divided into four periods (January 1-15, January 16-22, January 23-February 5 and after February 6). We used a susceptible-exposed-infectious- asymptomatic TRANS-recovered model to evaluate the effect of interventions. Results suggested that about 53.7% were imported from Wuhan. The median age TRANS was 47 years and 52.8% were women. Severity risk increased with age TRANS and associated with male TRANS and co-existing disorders. The attack rate TRANS peaked in the third period and drastically decreased afterwards across sex, age groups TRANS and geographic regions. Children TRANS younger than 5 years showed a higher attack rate TRANS than those aged TRANS of 6~19. The effective reproductive number TRANS decreased from 1.44 to 0.05 after the highest level emergency response since January 23. Overall, the non-pharmaceutical interventions have effectively mitigated the COVID-19 outbreak in Shenzhen, China. These findings may facilitate the introduction of public health policies in other countries and regions.

    Dynamics of SEAIQR Model with Saturated Type Treatment: A Case Study of Spain COVID-19

    Authors: Uttam Ghosh; Md Kamrujjaman; Jayanta Kumar Ghosh

    id:10.20944/preprints202005.0217.v1 Date: 2020-05-12 Source: Preprints.org

    Background: Outbreak of the Covid-19 is now an ongoing global health emergency. At the end of December 2019, the first infection MESHD was reported in Wuhan and the world did not pay attention to this extremely contaminated disease and plucked to react rapidly. The World is in an vulnerable state in disease spreading TRANS, facing a great loss of lives and socio-economic aspects also. That is why we have proposed a potential mathematical model with data analysis to predict and control the outcome of this pandemic. Methods: The model presented the epidemic dynamics of multiple compartments. We collected available online data of Spain. In primary step, we estimated the parameters using either the data analysis or reference papers. Then we did the data fitting analysis in comparison with the outcome of our mathematical results. The results of the system depended not only the parameters also on social consciousness. Results: It is found that disease progression in this model is determined by the basic reproductive ratio, $ R_0 TRANS$, the actual epidemic of $ R_0 TRANS$ and effective $R(t)$ of each day. If $ R_0 TRANS>1$, the number of latently infected individuals grows exponentially; endemic solution is stable while infection rate decays if $ R_0 TRANS<1$. The optimal control theory stated that vaccination and treatment strategies are highly effective for reducing both susceptible and infected population and to increase the recover rate high. In Spain, after state of alarm (quarantine) on 14 March 2020, reported cases increasing for 13 days only and from the 14th day, daily reported cases started to decline albeit with small fluctuation. Our proposed model approximates that the disease in Spain could be fully under control by after July 2020. Conclusion: Outbreak will be in control of health care system, reduce the death rate and will ensure social-economic stability.

    The Association of Social Distancing, Population Density, and Temperature with the SARS-CoV-2 Instantaneous Reproduction Number MESHD Reproduction Number TRANS in Counties Across the United States

    Authors: David Rubin; Jing Huang; Brian T Fisher; Antonio Gasparrini; Vicky Tam; Lihai Song; Xi Wang; Jason Kaufman; Kate Fitzpatrick; Arushi Jain; Heather Griffis; Koby Crammer; Gregory Tasian

    doi:10.1101/2020.05.08.20094474 Date: 2020-05-12 Source: medRxiv

    Importance: The Covid-19 pandemic has been marked by considerable heterogeneity in outbreaks across the United States. Local factors that may be associated with variation in SARS-CoV-2 transmission TRANS have not been well studied. Objective: To examine the association of county-level factors with variation in the SARS-CoV-2 reproduction number TRANS over time. Design: Observational study Setting: 211 counties in 46 states and the District of Columbia between February 25, 2020 and April 23, 2020. Participants: Residents within the counties (55% of the US population) Exposures: Social distancing as measured by percent change in visits to non-essential businesses, population density, lagged daily wet bulb temperatures. Main Outcomes and Measures: The instantaneous reproduction number TRANS (Rt) which is the estimated number of cases generated by one case at a given time during the pandemic. Results: Median case incidence was 1185 cases and fatality rate was 43.7 deaths per 100,000 people for the top decile of 21 counties, nearly ten times the incidence and fatality rate in the lowest density quartile. Average Rt in the first two weeks was 5.7 (SD 2.5) in the top decile, compared to 3.1 (SD 1.2) in the lowest quartile. In multivariable analysis, a 50% decrease in visits to non-essential businesses was associated with a 57% decrease in Rt (95% confidence interval, 56% to 58%). Cumulative temperature effects over 4 to 10 days prior to case incidence were nonlinear; relative Rt decreased as temperatures warmed above 32F to 53F, which was the point of minimum Rt, then increased between 53F and 66F, at which point Rt began to decrease. At 55F, and with a 70% reduction in visits to non-essential business, 96% of counties were estimated to fall HP below a threshold Rt of 1.0, including 86% of counties among the top density decile and 98% of counties in the lowest density quartile. Conclusions and Relevance: Social distancing, lower population density, and temperate weather change were associated with a decreased SARS-Co-V-2 Rt in counties across the United States. These relationships can inform selective public policy planning in communities during the SARS-CoV-2 pandemic.

    The effects of the clinical symptoms pneumonia HP-confirmation strategy of the COVID-19 epidemic in Wuhan, China

    Authors: Yanjin Wang; Pei Wang; Shudao Zhang; Hao Pan

    doi:10.21203/rs.3.rs-28619/v1 Date: 2020-05-12 Source: ResearchSquare

    Motivated by the quick control in Wuhan, China, and the rapid spread in other countries of COVID-19, we investigate the questions that what is the turning point in Wuhan by quantifying the variety of basic reproductive number TRANS after the lockdown city. The answer may help the world to control the COVID-19 epidemic. A modified SEIR model is used to study the COVID-19 epidemic in Wuhan city. Our model is calibrated by the hospitalized cases. The modeling result gives out that the means of basic reproductive numbers TRANS are 1.5517 (95% CI 1.1716-4.4283) for the period from Jan 25 to Feb 11, 2020, and 0.4738(95% CI 0.0997-0.8370) for the period from Feb 12 to Mar 10. The transmission TRANS rate fell HP after Feb 12, 2020 as a result of China’s COVID-19 strategy of keeping society distance and the medical support from all China, but principally because of the clinical symptoms to be used for the novel coronavirus pneumonia MESHD pneumonia HP (NCP) confirmation in Wuhan since Feb 12, 2020. Clinical diagnosis can quicken up NCP-confirmation such that the COVID-19 patients can be isolated without delay. So the clinical symptoms pneumonia HP-confirmation is the turning point of the COVID-19 battle of Wuhan. The measure of clinical symptoms pneumonia HP pneumonia MESHD-confirmation in Wuhan has delayed the growth HP and reduced size of the COVID-19 epidemic, decreased the peak number of the hospitalized cases by 96% in Wuhan. Our modeling also indicates that the earliest start date of COVID-19 in Wuhan may be Nov 2, 2019.ο»Ώ

    Evolving Transmission TRANS Network Dynamics of COVID-19 Cluster Infections in South Korea: a descriptive study

    Authors: Yejin Kim; Xiaoqian Jiang

    doi:10.1101/2020.05.07.20091769 Date: 2020-05-12 Source: medRxiv

    Background. Extensive contact tracing TRANS and testing in South Korea allows us to investigate the transmission TRANS dynamics of the COVID-19 into diverse local communities. Objective. Understand the critical aspects of transmission TRANS dynamics in a different age TRANS, sex, and clusters with various activities. Methods. We conducted a retrospective observational study with 3,127 confirmed cases TRANS' contact tracing TRANS data from the Center for Disease MESHD and Prevention (CDC) of South Korea. We investigated network property concerning infected persons' demographics and different infection clusters MESHD. Findings. Overall, women had higher centrality scores than men after week four, when the confirmed cases TRANS rapidly increased. Older adults TRANS have higher centrality than young/middle- aged TRANS adults TRANS after week 9. In the infection clusters MESHD, young/middle- aged TRANS adults TRANS' infection clusters MESHD (such as religious gatherings and gym facilities) have higher average path lengths and diameter than older adults TRANS' nursing home infection clusters MESHD. Interpretation. Some women had higher reproduction numbers TRANS and bridged successive transmission TRANS than men when the confirmed cases TRANS rapidly increased. Similarly, some older adults TRANS (who were not residents of nursing homes) had higher reproduction numbers TRANS and bridged successive transmission TRANS than young/middle- aged TRANS adults TRANS after the peak has passed. The young/middle- aged TRANS adults TRANS' religious gatherings and group workout have caused long successive transmissions TRANS. In contrast, the older adults TRANS' nursing homes were a small world where the transmissions TRANS within a few steps can reach out to many persons.

    Lessons from being challenged by COVID-19

    Authors: E. Tagliazucchi; P. Balenzuela; M. Travizano; G. B. Mindlin; P. D. Mininni

    id:2005.05853v1 Date: 2020-05-12 Source: arXiv

    We present results of different approaches to model the evolution of the COVID-19 epidemic in Argentina, with a special focus on the megacity conformed by the city of Buenos Aires and its metropolitan area, including a total of 41 districts with over 13 million inhabitants. We first highlight the relevance of interpreting the early stage of the epidemic in light of incoming infectious travelers from abroad. Next, we critically evaluate certain proposed solutions to contain the epidemic based on instantaneous modifications of the reproductive number TRANS. Finally, we build increasingly complex and realistic models, ranging from simple homogeneous models used to estimate local reproduction numbers TRANS, to fully coupled inhomogeneous (deterministic or stochastic) models incorporating mobility estimates from cell phone location data. The models are capable of producing forecasts highly consistent with the official number of cases with minimal parameter fitting and fine-tuning. We discuss the strengths and limitations of the proposed models, focusing on the validity of different necessary first approximations, and caution future modeling efforts to exercise great care in the interpretation of long-term forecasts, and in the adoption of non-pharmaceutical interventions backed by numerical simulations.

    A numerical simulation of the COVID-19 epidemic in Argentina using the SEIR model

    Authors: Juan E. Santos; Jose' M. Carcione; Gabriela B. Savioli; Patricia M. Gauzellino; Alejandro Ravecca; Alfredo Moras

    id:2005.06297v4 Date: 2020-05-12 Source: arXiv

    A pandemic caused by a new coronavirus has spread worldwide, affecting Argentina. We implement an SEIR model to analyze the disease evolution in Buenos Aires and neighbouring cities. The model parameters are calibrated using the number of casualties officially reported. Since infinite solutions honour the data, we show different cases. In all of them the reproduction ratio $ R_0 TRANS$ decreases after early lockdown, but then raises, probably due to an increase in contagion in highly populated slums. Therefore it is mandatory to reverse this growing trend in $ R_0 TRANS$ by applying control strategies to avoid a high number of infectious and dead individuals. The model provides an effective procedure to estimate epidemic parameters (fatality rate, transmission TRANS probability, infection MESHD and incubation periods TRANS) and monitor control measures during the epidemic evolution.

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MeSH Disease
Human Phenotype
Transmission
Seroprevalence


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