Corpus overview


Overview

MeSH Disease

Human Phenotype

Pneumonia (157)

Fever (105)

Cough (102)

Falls (48)

Fatigue (26)


Transmission

Seroprevalence
    displaying 1391 - 1400 records in total 2442
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    Early transmission TRANS dynamics and control of COVID-19 in a southern hemisphere setting: Lima-Peru, February 29th-March 30th, 2020 .

    Authors: Cesar V. Munayco; Amna Tariq; Richard Rothenberg; Gabriela G Soto-Cabezas; Mary F. Reyes; Andree Valle; Leonardo Rojas-Mezarina; Cesar Cabezas; Manuel Loayza; - COVID-19 Peru COVID-19 working group; Gerardo Chowell

    doi:10.1101/2020.04.30.20077594 Date: 2020-05-05 Source: medRxiv

    The COVID-19 pandemic that emerged in Wuhan China has generated substantial morbidity and mortality impact around the world during the last four months. The daily trend in reported cases has been rapidly rising in Latin America since March 2020 with the great majority of the cases reported in Brazil followed by Peru as of April 15th, 2020. Although Peru implemented a range of social distancing measures soon after the confirmation of its first case on March 6th, 2020, the daily number of new COVID-19 cases continues to accumulate in this country. We assessed the early COVID-19 transmission TRANS dynamics and the effect of social distancing interventions in Lima, Peru. We estimated the reproduction number TRANS, R, during the early transmission TRANS phase in Lima from the daily series of imported and autochthonous cases by the date of symptoms onset TRANS as of March 30th, 2020. We also assessed the effect of social distancing interventions in Lima by generating short-term forecasts grounded on the early transmission TRANS dynamics before interventions were put in place. Prior to the implementation of the social distancing measures in Lima, the local incidence curve by the date of symptoms onset TRANS displays near exponential growth dynamics with the mean scaling of growth parameter, p, estimated at 0.9 (95%CI: 0.9,1.0) and the reproduction number TRANS at 2.3 (95% CI: 2.0, 2.5). Our analysis indicates that school closures and other social distancing interventions have helped slow down the spread of the novel coronavirus, with the nearly exponential growth trend shifting to an approximately linear growth trend soon after the broad scale social distancing interventions were put in place by the government. While the interventions appear to have slowed the transmission TRANS rate in Lima, the number of new COVID-19 cases continue to accumulate, highlighting the need to strengthen social distancing and active case finding efforts to mitigate disease MESHD transmission TRANS in the region.

    COVID-19 herd immunity strategies: walking an elusive and dangerous tightrope

    Authors: Tobias Brett; Pejman Rohani

    doi:10.1101/2020.04.29.20082065 Date: 2020-05-05 Source: medRxiv

    The rapid growth in cases of COVID-19 has threatened to overwhelm healthcare systems in multiple countries. In response, severely affected countries have had to consider a range of public health strategies achieved by implementing non-pharmaceutical interventions. Broadly, these strategies have fallen HP into two categories: i) "mitigation", which aims to achieve herd immunity by allowing the SARS-CoV-2 virus to spread through the population while mitigating disease MESHD burden, and ii) "suppression", aiming to drastically reduce SARS-CoV-2 transmission TRANS rates and halt endogenous transmission TRANS in the target population. Using an age TRANS-structured transmission TRANS model, parameterised to simulate SARS-CoV-2 transmission TRANS in the UK, we assessed the prospects of success using both of these approaches. We simulated a range of different non-pharmaceutical intervention scenarios incorporating social distancing applied to differing age groups TRANS. We found that it is possible to suppress SARS-CoV-2 transmission TRANS if social distancing measures are sustained at a sufficient level for a period of months. Our modelling did not support achieving herd immunity as a practical objective, requiring an unlikely balancing of multiple poorly-defined forces. Specifically, we found that: i) social distancing must initially reduce the transmission TRANS rate to within a narrow range, ii) to compensate for susceptible depletion, the extent of social distancing must be vary over time in a precise but unfeasible way, and iii) social distancing must be maintained for a long duration (over 6 months).

    Transmission TRANS dynamics of coronavirus disease MESHD 2019 outside of Daegu-Gyeongsangbuk provincial region in South Korea

    Authors: Sukhyun Ryu; Sheikh Ali; Cheolsun Jang; Baekjin Kim; Benjamin J Cowling

    doi:10.1101/2020.04.28.20082750 Date: 2020-05-05 Source: medRxiv

    We analyzed transmission TRANS of coronavirus disease MESHD 2019 in South Korea. We estimated that non-pharamaceutical measures reduced the immediate transmissibility TRANS by maximum of 34% for coronavirus disease MESHD 2019. Continuous efforts are needed for monitoring the transmissibility TRANS to optimize epidemic control.

    The Role of Temperature in COVID-19 Disease MESHD Severity and Transmission TRANS Rates

    Authors: Dominique Kang; Clifford Ellgen

    id:10.20944/preprints202005.0070.v1 Date: 2020-05-05 Source: Preprints.org

    Air temperature and body temperature may influence COVID-19 disease MESHD severity and transmission TRANS rates. In vitro data indicate that SARS-CoV-2 loses infectivity at normal core body temperature (37°C); however, small reductions in temperature proximate to 37°C may result in substantially increased viral stability. If these results are representative of viral decay rates in vivo, then cooler temperatures in the body may enable more rapid viral growth. Breathing cool air—even as warm as 25°C—cools upper respiratory tract (URT) surfaces to several degrees below body temperature, and these lower temperatures may make the URT exceptionally conducive to SARS-CoV-2 replication. Increased URT viral load may enable more effective transmission TRANS. Additionally, because SARS-CoV-2 infection MESHD may frequently begin in the URT before spreading through the body, an increased rate of viral replication in the URT early in the disease MESHD course may result in more rapid progression of disease MESHD, potentially causing more severe adverse outcomes. Core body temperature may also be a factor in disease MESHD severity, as lower core body temperatures may enable more rapid viral growth. The significance of air temperature and body temperature to disease MESHD severity and transmission TRANS rates may inform preventative measures and post-exposure prophylaxis treatments for COVID-19.

    The geography of COVID-19 spread in Italy and implications for the relaxation of confinement measures

    Authors: Enrico Bertuzzo; Lorenzo Mari; Damiano Pasetto; Stefano Miccoli; Renato Casagrandi; Marino Gatto; Andrea Rinaldo

    doi:10.1101/2020.04.30.20083568 Date: 2020-05-05 Source: medRxiv

    We examine the spread of Severe Acute Respiratory Syndrome MESHD Coronavirus 2 (SARS-CoV-2) in Italy, to address the appropriate methodological choices for the design of selective relaxations of the current containment measures. Pressing relevance stems from the need to restart the economy dramatically affected by the lockdown. We employ a spatially explicit, data-intensive model of the patterns of disease MESHD disease spread TRANS spread in Italy, which devotes proper attention to the paramount role of inapparent infections MESHD. We aim at providing tools to: estimate the baseline trajectory, i.e. the expected unfolding of the outbreak if the current containment measures were kept in place indefinitely; assess possible deviations from the baseline, should relaxations of the current lockdown result in increased disease MESHD transmission TRANS; and estimate the isolation effort required to prevent a resurgence of the outbreak. A 40% increase in effective transmission TRANS as a result of the loosening of confinement measures would yield an epidemic curve that shows a major rebound, larger than the previous peaks in most regions. A control effort capable of isolating a daily percentage of approximately 5.5% of the exposed and highly infectious individuals proves necessary to counterbalance such an increase and maintain the epidemic curve onto the decreasing baseline trajectory. We explore several scenarios, provide the basic data to design the related control strategies, and discuss their feasibility. Should suitable control via tracing TRANS and testing prove unfeasible, stop-and-go enforcement or delay of the lockdown relaxations would be necessary to reduce the isolation effort required to maintain the epidemic trajectory under control.

    Does weather affect the growth rate of COVID-19, a study to comprehend transmission TRANS dynamics on human health

    Authors: Arjun Sil; Vanapalli Naveen Kumar

    doi:10.1101/2020.04.29.20085795 Date: 2020-05-05 Source: medRxiv

    The undefendable outbreak of novel coronavirus (SARS-COV-2) lead to a global health emergency MESHD due to its higher transmission TRANS rate and longer symptomatic duration, created a health surge in a short time. Since Nov 2019 the outbreak in China, the virus is spreading exponentially everywhere. The current study focuses on the relationship between environmental parameters and the growth rate of COVID-19. The statistical analysis suggests that the temperature changes retarded the growth rate and found that -6.28{degrees}C and +14.51{degrees}C temperature is the favorable range for COVID-19 growth. Gutenberg- Richter's relationship is used to estimate the mean daily rate of exceedance of confirmed cases TRANS concerning the change in temperature. Temperature is the most influential parameter that reduces the growth at the rate of 13-16 cases/day with a 1{degrees}C rise in temperature.

    Mapping the Spread of COVID-19 Outbreak in India

    Authors: Vanshika Bidhan; Bhavini Malhotra; Mansi Pandit; Narayanan Latha

    id:10.20944/preprints202005.0051.v1 Date: 2020-05-05 Source: Preprints.org

    Background & Objectives: The global pandemic caused by novel coronavirus SARS-CoV-2 has claimed several lives worldwide. With the virus gathering rapid spread, the world has witnessed increasing number of confirmed cases TRANS and mortality rate, India is not far behind with approximately 37,000 affected individuals as on May 2, 2020. The ongoing pandemic has raised several questions which need to be answered by analysis of transmission TRANS of the infection MESHD. The data has been collected on daily basis from WHO and other sites. We have represented the data collated graphically using statistical packages, R and other online softwares. The present study provides a holistic overview of the spread of COVID-19 infection MESHD in India. Methods: Real-time data query was done based on daily observations using publicly available data from reference websites for COVID-19 and other government official reports for the period (15th February, 2020 to April 28th, 2020). Statistical analysis was performed to draw important inferences regarding COVID-19 trend in India. Results: A decrease in growth rate of cases due to COVID-19 in India post lockdown and improvement in recovery rate during the month of April was identified. The case fatality rate was estimated to be 3.22% of the total reported cases. State-wise analysis revealed a deteriorating situation in states of Maharashtra and Gujarat among others as cases continued to increase rapidly there. A positive linear correlation between the number of deaths MESHD and total cases and exponential relation between population density and number of cases reported per square km was established. Interpretation & Conclusions: Despite early preventive measures taken up by the Government of India, the increasing number of cases in India is a concern. This study compiles state-wise and district-wise data to report the daily confirmed cases TRANS, case fatalities and strategies adopted in the form of case studies. Understanding the transmission TRANS spread of SARS-CoV-2 in a diverse and populated country like India will be crucial in assessing the effectiveness of control policies towards the spread of COVID-19 infection MESHD.

    Worldwide Effectiveness of Various Non-Pharmaceutical Intervention Control Strategies on the Global COVID-19 Pandemic: A Linearised Control Model

    Authors: Jacques Naude; Bruce Mellado; Joshua Choma; Fabio Correa; Salah Dahbi; Barry Dwolatzky; Leslie Dwolatzky; Kentaro Hayasi; Benjamin Lieberman; Caroline Maslo; Kgomotso Monnakgotla; Xifeng Ruan; Finn Stevenson

    doi:10.1101/2020.04.30.20085316 Date: 2020-05-05 Source: medRxiv

    Background COVID-19 is a virus which has lead to a global pandemic. Worldwide, more than 130 countries have imposed severe restrictions, which form part of a set of non-pharmaceutical interventions (NPI)s. We aimed to quantify the country-specific effects of these NPIs and compare them using the Oxford COVID-19 Government Response Tracker (OxCGRT) stringency index, p, as a measure of NPI stringency. Methods We developed a dual latent/observable Susceptible Infected Recovered Deaths MESHD (SIRD) model and applied it on each of 22 countries and 25 states in the US using publicly available data. The observable model parameters were extracted using kernel functions. The regression of the transmission TRANS rate, {beta}, as a function of p in each locale was modeled through the intervention leverage, s, an initial transmission TRANS rate, {beta}0 and a typical adjustment time, br-1. Results The world average for the intervention leverage, s=0.01 (95% CI 0.0102 - 0.0112) had an ensemble standard deviation of 0.0017 (95% C.I. 0.0014 - 0.0021), strongly indicating a universal behavior. Discussion Our study indicates that removing NPIs too swiftly will result in the resurgence of the spread within one to two months, in alignment with the current WHO recommendations. Moreover, we have quantified and are able to predict the effect of various combinations of NPIs. There is a minimum NPI level, below which leads to resurgence of the outbreak (in the absence of pharmaceutical and clinical advances). For the epidemic to remain sub-critical, the rate with which the intervention leverage s increases should outpace that of the relaxation of NPIs.

    The impact of asymptomatic TRANS individuals on the strength of public health interventions to prevent the second outbreak of COVID-19

    Authors: Xiaochen Wang; Shengfeng Wang; Yueheng Lan; Xiaofeng Tao; Jinghua Xiao

    doi:10.21203/rs.3.rs-27142/v1 Date: 2020-05-05 Source: ResearchSquare

    The pandemic of coronavirus disease MESHD 2019(COVID-19) has threatened the social and economic structure all around the world. Generally, COVID-19 has three possible transmission TRANS routes, including pre-symptomatic, symptomatic, and asymptomatic TRANS transmission TRANS, among which the last one has brought a severe challenge for the containment of the disease MESHD. One core scientific question is to understand the influence of asymptomatic TRANS individuals and of the strength of control measures on the evolution of the disease MESHD, particularly on a second outbreak of the disease MESHD. To explore these issues, we proposed a novel compartmental model that takes the infection of asymptomatic MESHD asymptomatic TRANS individuals into account. We get the relationship between asymptomatic TRANS individuals and critical strength of control measures theoretically. Furthermore, we verify the reliability of our model and the accuracy of the theoretical analysis by using the real confirmed cases TRANS of COVID-19 contamination. Our results, showing the importance of the asymptomatic TRANS population on the control measures, would provide useful theoretical reference to the policymakers and fuel future studies of COVID-19.

    A study on COVID-19 transmission TRANS dynamics: Stability analysis of SEIR model with Hopf bifurcation for effect of time delay

    Authors: M.Rasha; S.Balamuralitharan

    doi:10.21203/rs.3.rs-27137/v1 Date: 2020-05-05 Source: ResearchSquare

    This paper deals with a general SEIR model for the coronavirus disease MESHD 2019 (COVID-19) with the effect of time delay proposed. We get the stability theorems for disease MESHD-free equilibrium and provide adequate situations of the COVID-19 transmission TRANS dynamics equilibrium of present and absent cases. A Hopf bifurcation parameter $\tau$ is the effects of time delay and we demonstrate that the locally asymptotic TRANS stable is present equilibrium. The Reproduction number TRANS is brief in less than or greater than one, and it effectively controlling the COVID-19 infection MESHD outbreak, and subsequently reveals insight into understanding the patterns of the flare-up. The numerical experiment is calculated to help the theoretical outcomes. 

The ZB MED preprint Viewer preVIEW includes all COVID-19 related preprints from medRxiv and bioRxiv, from ChemRxiv, from ResearchSquare, from arXiv and from Preprints.org and is updated on a daily basis (7am CET/CEST).

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MeSH Disease
Human Phenotype
Transmission
Seroprevalence


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