Corpus overview


Overview

MeSH Disease

Sneezing (37)

Cough (35)

Infections (17)

Disease (13)

Fever (9)


Human Phenotype

Transmission

Seroprevalence
    displaying 1 - 10 records in total 37
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    Extended lifetime of respiratory droplets in a turbulent vapour puff and its implications on airborne disease MESHD transmission TRANS

    Authors: Kai Leong Chong; Chong Shen Ng; Naoki Hori; Rui Yang; Roberto Verzicco; Detlef Lohse

    id:2008.01841v1 Date: 2020-08-04 Source: arXiv

    To mitigate the COVID-19 pandemic, it is key to slow down the spreading of the life-threatening coronavirus (SARS-CoV-2). This spreading mainly occurs through virus-laden droplets expelled at speaking, coughing MESHD coughing HP, sneezing MESHD sneezing HP, or even breathing. To reduce infections MESHD through such respiratory droplets, authorities all over the world have introduced the so-called "2-meter distance rule" or "6-foot rule". However, there is increasing empirical evidence, e.g. through the analysis of super-spreading events, that airborne transmission TRANS of the coronavirus over much larger distances plays a major role with tremendous implications for the risk assessment of coronavirus transmission TRANS. Here we employ direct numerical simulations of a typical respiratory aerosol in a turbulent jet of the respiratory event within a Lagrangian-Eulerian approach with 5000 droplets, coupled to the ambient velocity, temperature, and humidity fields to allow for exchange of mass and heat and to realistically account for the droplet evaporation under different ambient conditions. We found that for an ambient relative humidity RH of 50% the lifetime of the smallest droplets of our study with initial diameter of 10 um gets extended by a factor of more than 30 as compared to what is suggested by the classical picture of Wells, due to collective effects during droplet evaporation and the role of the respiratory humidity, while the larger droplets basically behave ballistically. With increasing ambient RH the extension of the lifetimes of the small droplets further increases and goes up to 150 times for 90% RH, implying more than two meters advection range of the respiratory droplets within one second. Smaller droplets live even longer and travel TRANS further. Our results may explain why COVID-19 superspreading events can occur for large ambient RH such as in cooled-down meat-processing plants or in pubs with poor ventilation.

    Clinical characteristics of neonates with coronavirus disease MESHD 2019 (COVID-19): a systematic review

    Authors: Yuan Hu; Jing Xiong; Yuan Shi

    doi:10.21203/rs.3.rs-50795/v1 Date: 2020-07-29 Source: ResearchSquare

    This study aimed to summarize the existing literature on severe acute respiratory syndrome MESHD coronavirus 2 (SARS-CoV-2) infection in newborns to clarify the clinical features and outcomes of neonates with COVID-19. A systematic search was performed in PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang Data, and VIP databases from January 1, 2019 to April 30, 2020. The references of relevant studies were also searched. A descriptive summary was organized by aspects of clinical presentations (symptoms, laboratory examinations, and imaging) and outcomes. We identified 14 studies reporting 18 newborns with COVID-19. The most common clinical manifestations were fever MESHD fever HP (62.5%), shortness of breath (50.0%), diarrhea MESHD diarrhea HP/ vomiting MESHD vomiting HP/feeding intolerance(43.8%), cough MESHD cough HP (37.5%), dyspnea MESHD dyspnea HP (25.0%), and nasal congestion/runny nose/ sneeze MESHD sneeze HP(25.0%). Atypical symptoms included jaundice MESHD jaundice HP and convulsion. Lymphocyte numbers decreased in 5 cases, and radiographic findings were likely to show pneumonia MESHD pneumonia HP. All newborns recovered and discharged from the hospital, and there was no death MESHD.Conclusion: Clinical symptoms of neonatal SARS-CoV-2 infection MESHD are atypical, most of them are mild. Up to now, the prognosis of newborns is good, and there is no death MESHD. Intrauterine vertical transmission TRANS is possible, but confirmed evidence is still lacking. The Long-term follow-up of potential influences of SARS-CoV-2 infection MESHD on neonates need further exploration.

    Coronavirus Disease MESHD (COVID-19): Reviews, Applications, and Current Status

    Authors: Tanweer Alam

    id:10.20944/preprints202007.0641.v1 Date: 2020-07-26 Source: Preprints.org

    Currently, the COVID‐19 has directly affected the millions of humans lives. The symptoms of the disease MESHD involving fever MESHD fever HP, malaise, chest infection MESHD, and breathing difficulties, were identified, and its existence is continuously becoming restructured. The World Health Organization (WHO) had mentioned the wide diagnostics test besides COVID-19 that would also assist medical facilities to recognize infectious diseases as well MESHD as currently focusing efficiently on preventing and afterward defeating this viral disease MESHD. The infection MESHD is usually transmitted among human beings in direct contact, greatest through the liquid bubbles generated through cough MESHD cough HP, sneeze MESHD sneeze HP, or speaking. This paper reviews the COVID 19 pandemic, its history, current updates, contact tracing TRANS applications, and use of emerging technologies like the Internet of Things (IoT) and Blockchain for stopping the spreading and provide service online to the patient from a distance.

    Pandemic of Coronavirus (COVID-19) in Saudi Arabia

    Authors: Maryam Ahmed Awaji

    id:10.20944/preprints202007.0549.v1 Date: 2020-07-23 Source: Preprints.org

    Introduction Most cases of COVID-19 coronavirus infection MESHD occurred in the Chinese city of Wuhan at the end of December 2019 in the form of acute pneumonia MESHD pneumonia HP. COVID-19 virus infects people of all ages TRANS. The most affected elderly TRANS people with underlying medical conditions. This may cause various symptoms such as fever MESHD fever HP, difficulty breathing, lung infection MESHD, coughing MESHD coughing HP and sneezing MESHD sneezing HP. Aim The aim of the present study to highlight the COVID-19 pandemic in Saudi Arabia. Method A search was conducted using the relevant keywords to retrieve the studies conducted in Saudi Arabia regarding COVID-19. The search was by Google Scholar, Pub MED, and Twitter. Conclusion The COVID-19 pandemic carries multiple-risk, and public health groups, such as the United States' Centres for Disease MESHD Control and Prevention (CDC) and the World Health Organisation (WHO), are monitoring the pandemic and posting updates on their website. These groups have also made recommendations on disease MESHD prevention and treatment, and according to the Saudi Centres for Disease MESHD Control, they have also included the necessary public health measures for mandatory reporting by calling a certain number and through the e-health monitoring network.

    Impact of Meteorological factors and population size on the transmission TRANS of Micro-size respiratory droplets based Coronavirus: A brief study of highly infected cities in Pakistan

    Authors: Iram Shahzadi; Anum Shahzadi; Junaid Haider; Sadia Naz; Rai M Aamir; Ali Haider; Hafiz Rizwan Sharif; Imran Mahmood Khan; Muhammad Ikram

    doi:10.1101/2020.07.14.20153544 Date: 2020-07-17 Source: medRxiv

    Ongoing Coronavirus epidemic (COVID-19) identified first in Wuhan, China posed huge impact on public health and economy around the globe. Both cough MESHD cough HP and sneeze MESHD sneeze HP based droplets or aerosols encapsulated COVID-19 particles are responsible for air borne transmission TRANS of this virus and caused unexpected escalation and high mortality worldwide. Current study intends to investigate correlation of COVID-19 epidemic with meteorological parameters particularly, temperature, rainfall, humidity, and wind speed along with population size. Data set of COVID-19 for highly infected cities of Pakistan was collected from the official website of National Institute of health (NIH). Spearman rank (rs) correlation coefficient test employed for data analysis revealed significant correlation between temperature minimum (TM), temperature average (TA), wind speed (WS) and population size (PS) with COVID-19 pandemic. Furthermore, receiver operating characteristics (ROC) curve was used to analyze the sensitivity SERO of TA, WS, and PS on transmission TRANS rate of COVID-19 in selected cities of Pakistan. The results obtained for sensitivity SERO and specificity analysis for all selected parameters signifies sensitivity SERO and direct correlation of COVID-19 transmission TRANS with temperature variation, WS and PS. Positive correlation and strong association of PS parameter with COVID-19 pandemic suggested need of more strict actions and control measures for highly populated cities. These findings will be helpful for health regulatory authorities and policymakers to take specific measures to combat COVID-19 epidemic in Pakistan.

    Exposure assessment for airborne transmission TRANS of SARS-CoV-2 via breathing, speaking, coughing MESHD coughing HP and sneezing MESHD sneezing HP

    Authors: Jack F. Schijven; Lucie C Vermeulen; Arno Swart; Adam Meijer; Erwin Duizer; Ana Maria de Roda Husman

    doi:10.1101/2020.07.02.20144832 Date: 2020-07-05 Source: medRxiv

    Background Evidence for indoor airborne transmission TRANS of SARS-CoV-2 is accumulating. If SARS-CoV-2 also spreads via aerosols, this has implications for measures taken to limit transmission TRANS. Objectives The aim of this study is to assess exposure to airborne SARS-CoV-2 particles from breathing, speaking, coughing MESHD coughing HP and sneezing MESHD sneezing HP in an indoor environment. Methods An exposure assessment model was developed to estimate numbers of SARS-CoV-2 particles in aerosol droplets, expelled during breathing, speaking, coughing MESHD coughing HP and sneezing MESHD sneezing HP by an infected person in an unventilated indoor environment, and subsequent inhalation by one or more persons. Scenarios encompass a range of virus concentrations, room sizes and exposure times. Results The calculated total volume of expelled aerosol droplets was highest for a sneeze MESHD sneeze HP, followed by a cough MESHD cough HP and speaking for 20 minutes, and lastly breathing for 20 minutes. A few to as much as tens of millions of virus particles were expelled. Exposure probability strongly depends on the viral concentration in mucus, as well as on the scenario. Exposure probabilities were generally below 1% at a virus concentration in mucus below 10^5 per mL for all scenarios, increasing steeply at different higher concentrations. According to nose / throat swab data collected from patients, 75%, 50% and 5% of infected individuals carry an estimated number of SARS-CoV-2 per mL mucus of at least 10^5, 10^6 and 10^8, respectively. Discussion Exposure to SARS-CoV-2 via aerosols generated during breathing, speaking, coughing MESHD coughing HP and sneezing MESHD sneezing HP in an unventilated indoor environment is possible. This study forms a basis to estimate probabilities of exposure to SARS-Cov-2 by airborne transmission TRANS in indoor spaces. As long as it is uncertain what fraction of the airborne virus particles is infectious and as long as a dose response relation is lacking, it is recommended to be precautious.

    Symptomatology of Coronavirus Disease MESHD 2019 (COVID-19) - Lessons from A Meta-Analysis Across 13 Countries

    Authors: Champika Saman Kumara Gamakaranage; Dineshani Hettiarachchi; Dileepa Ediriweera; Saroj Jayasinghe

    doi:10.21203/rs.3.rs-39412/v1 Date: 2020-07-01 Source: ResearchSquare

    Background: COVID-19 pandemic has resulted in varying clinical manifestations and mortality rates. There is no consensus on the symptomatology that would guide researchers and clinicians.Objective: The objective of the study was to identify symptoms and their frequencies of coronavirus disease MESHD 2019 with a meta-analysis of studies from several countries. Data sources: A systematic review using PubMed and Google Scholar data sources and reference tracing TRANS were used to identify 7176 relevant articles. Eligibility criteria: Suitable articles were selected manually with selection criteria and 14 original articles included for meta-analysis. Data abstraction analysis: PRISMA guideline was used for abstracting data. Then a table was generated by feeding it with numbers and proportions of each symptom described in original studies. A meta-analysis was carried out using random effect models on each symptom separately across the studies and their prevalence SERO rates and 95% confident intervals calculated.Results: We identified 14 relevant scientific papers, either cross-sectional or cohort studies and analyzed. There were 2,660 cases of COVID-19. he majority were from China (n=2,439, 91.7%) and remainder from the Netherlands, Italy, Korea and India and one article from Europe. There was a total of 32 symptoms (i.e. present in >50% of patients): fever (79.56%, 95% CI: 72.17-86.09%), malaise (63.3%, 95% CI: 53.1 – 73.0%), cough MESHD cough HP (56.7. %, 95% CI: 48.6 - 64.6 %) and cold (55.6%, 95% CI: 45.2 – 65.7%). Symptoms of intermediate incidence (5-49%) were; anosmia HP, sneezing MESHD sneezing HP, ocular pain HP pain MESHD, fatigue MESHD fatigue HP, sputum production, arthralgia MESHD arthralgia HP, tachypnea MESHD tachypnea HP, palpitation HP, headache MESHD headache HP, chest tightness HP, shortness of breath, chills MESHD chills HP, myalgia MESHD myalgia HP, sore throat, anorexia MESHD anorexia HP, weakness, diarrhea MESHD diarrhea HP, rhinorrhea HP, dizziness MESHD, nausea MESHD nausea HP, altered level of consciousness, vomiting MESHD vomiting HP and abdominal pain MESHD abdominal pain HP. Rare symptoms (<5% of patients) were: tonsil swelling, haemoptysis, conjunctival injection, lymphadenopathy MESHD lymphadenopathy HP and rash were uncommon symptoms of coronavirus disease MESHD (<5%).Conclusion and implications of key findings: We found (25/32) symptoms to be present in =>5% of cases which could be considered as “typical” symptoms of COVID-19. The list of symptoms we identified are different from those documents released by the WHO, CDC, NHS, Chinese CDC, Institute Pasteur and Mayo Clinic. The compiled list would be useful for future researchers to document a comprehensive picture of the illness.

    Puff trains in speaking produce long-range turbulent jet-like transport potentially relevant to asymptomatic TRANS spreading of viruses

    Authors: Manouk Abkarian; Simon Mendez; Nan Xue; Fan Yang; Howard A. Stone

    id:2006.10671v1 Date: 2020-06-18 Source: arXiv

    Droplet generation and transport during coughing MESHD coughing HP and sneezing MESHD sneezing HP has been studied for decades to characterize disease MESHD transmission TRANS by symptomatic individuals. Nevertheless, many reports document that asymptomatic TRANS and presymptomatic individuals contribute to the spread of COVID-19, probably during conversations in social interactions HP social interactions TRANS. Researchers have shown that droplet emission occurs during speech, yet there are few quantitative studies of the flows that provide the transport mechanism; the relevant fluid dynamics is largely unstudied. This lack of quantitative characterization means that when virus is present there is little public health guidance for understanding risk and mitigation strategies, e.g. the "six-foot rule". Here we analyze flows during breathing and speaking, including linguistic features, using order-of-magnitudes estimates, numerical simulations, and laboratory experiments. We show how plosive sounds like `P' are associated with vortical structures, leading to rapid transport over half a meter in a split second. When produced individually, puffs decay over a meter, with the distance traveled TRANS in time $t$ scaling as $L\sim t^{1/4}$, and mix with the slower environmental circulation. In contrast, the transport of exhaled material over time scales longer than a few seconds, characteristic of speech, which is effectively a train of puffs, is a conical turbulent jet with a scaling law $L\sim t^{1/2}$. Typically, the exhaled air in front of a speaker extends 2 m after 30 seconds of normal speech. We believe this work will inform thinking about aerosol transport in disease MESHD transmission TRANS for humans and other animals, and yield a better understanding of linguistic aerodynamics, i.e., aerolinguistics.

    Not even the air of empty spaces is coronavirus free (Two meters is not a safe distance)

    Authors: Edilson Crema

    id:2006.08823v1 Date: 2020-06-15 Source: arXiv

    A key safety measure encouraged by health authorities to avoid the SARS-CoV-2 spreading is the distance of one to two meters between people. This recommended two-meters distance is mainly based on short-distance contagion, when infected drops are expelled during a speech, coughing MESHD coughing HP, or sneezing MESHD sneezing HP and directly hit another person. The dangerous form of airway contamination caused by droplets that remain suspended in the air for several hours has been almost ignored. However, the theoretical calculations performed in this work, recent experiments, and the accumulated knowledge in this and other epidemics indicate that, because of the airborne transmission TRANS, there is no safe distance to the coronavirus, either indoors or in open places. Recent investigations have confirmed not only the presence of the coronavirus in droplets suspended in the air but that these viruses remain active for several hours. Furthermore, significant indirect evidence of this means of transmission TRANS is the great difference in contagion between Brazilian regions in the current outbreak. While the Amazonian states have a contamination rate greater than 20%, in the southern states of the country this rate is less than 1%, despite high temperatures in the Northern region. Notwithstanding the social and economic differences between these regions, it seems that the extremely high humidity of the forest air prolongs the survival of the viruses in the drops in the external environment. Our theoretical calculations explain empirical observations from recent epidemiological studies and strengthen the need to use, not only a mask but also protective glasses throughout the population in the same way that they are mandatory for health professionals. Besides, our calculations show how air conditioning and heating systems can increase contagion. Finally, we suggest measures that could reduce the spread of the pandemic.

    Study of Air Curtain in Context of Individual Protection from Exposure to Coronavirus (SARS-CoV-2) Contained in Cough MESHD Cough HP-Generated Fluid Particles

    Authors: Alexander S. Sakharov; Konstantin Zhukov

    id:2006.11411v3 Date: 2020-06-15 Source: arXiv

    The ongoing respiratory COVID-19 pandemic has heavily impacted the social and private lives of the majority of the global population. This infection MESHD is primarily transmitted via virus-laden fluid particles (i.e., droplets and aerosols) that are formed in the respiratory tract of infected individuals and expelled from the mouth in the course of breathing, talking, coughing MESHD coughing HP, and sneezing MESHD sneezing HP. To mitigate the risk of virus transmission TRANS, in many places of the world, the public has been asked or even obliged to use face covers. It is plausible that in the years ahead we will see the use of face masks, face shields and respirators become a normal practice in our life. However, wearing face covers is uncomfortable in some situations, like, for example, in summer heat, while staying on beaches or at hotel swimming pools, doing exercises in gyms, etc. Also, most types of face cover become contaminated with time and need to be periodically replaced or disinfected. These nuisances are caused by the fact that face covers are based on material barriers, which prevent inward and outward propagation of aerosol and droplets containing the pathogen. Applying well established gas-particle flow formalism, we study a non-material based protection barrier created by a flow of well directed down stream of air across the front of the open face. The~protection is driven by dragging virus-laden particles inside the width of the air flow and hence, as a consequence, displacing them away from their primary trajectories. The study, shows that such, potentially portable, air curtains can effectively provide both inward and outward protection and serve as an effective personal protective equipment (PPE) mitigating human to human transmission TRANS of virus infection MESHD like COVID-19.

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MeSH Disease
Human Phenotype
Transmission
Seroprevalence


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