scholarly journals COVID-19 epidemic trends from a Self-Assessment Web Application in France: Observational Study (Preprint)

2020 ◽  
Author(s):  
Fabrice Denis ◽  
Arnaud Fontanet ◽  
Yann-Mael Le Douarin ◽  
Florian Le Goff ◽  
Stephan Jeanneau ◽  
...  
Keyword(s):  
Web Application ◽  
Large Scale ◽  
Correlation Coefficients ◽  
Young Population ◽  
Rt Pcr ◽  
Self Assessment ◽  
Emergency Visits ◽  
Spatially Correlated ◽  
Participatory Surveillance ◽  
Second Wave

BACKGROUND We developed a self-assessment and participatory surveillance web-application for coronavirus disease (COVID-19), which was launched in France in March 2020. OBJECTIVE We compared daily large-scale RT-PCR tests results to daily connections to a self-triage application by anosmic users to assess dynamics of emergency visits, hospitalizations and ICU admissions for COVID-19 positive patients in France. METHODS Between 3/21/2020 and 11/18//2020, users of maladiecoronavirus.fr self-triage application were asked questions about COVID-19 symptoms. Data of daily hospitalizations, large-scale RT-PCR positive tests, emergency visits and ICU entrances for COVID-19 patients were compared to data of anosmic users of the applications. RESULTS As of November 18, 2020, 575,214 users reported recent anosmia on near 13 Million responders. Daily anosmia reported during the peak of connections to the application on September 16 were spatially correlated with daily COVID-19–related hospitalizations peak which occurred in November (spearman correlation coefficients=0.77, p<.001). Decrease of the connections of anosmic users after the main peaks of connections preceded the decrease of daily hospitalizations by 10 and 9 days during the first and the second outbreak waves respectively although the decrease of RT-PCR positive tests occurred only 2 days before daily hospitalizations during the second wave. CONCLUSIONS A peak of daily reported anosmia in young adults was observed 49 days before the peak of the hospitalizations corresponding to the first phase of a large-scale contamination of young population followed by older people leading to hospitalization’s peak in November. Data of anosmic users of a national widespread self-assessment application can be a relevant tool to anticipate outbreak surge, and hospitalizations and ICU decrease of COVID-19 patients. CLINICALTRIAL ClinicalTrials.gov NCT04331171

scholarly journals Epidemiological Observations on the Association Between Anosmia and COVID-19 Infection: Analysis of Data From a Self-Assessment Web Application

10.2196/19855 ◽  
2020 ◽  
Vol 22 (6) ◽  
pp. e19855 ◽  
Author(s):  
Fabrice Denis ◽  
Simon Galmiche ◽  
Aurélien Dinh ◽  
Arnaud Fontanet ◽  
Arnaud Scherpereel ◽  
...  
Keyword(s):  
Web Application ◽  
Correlation Coefficients ◽  
Warning Signs ◽  
Phone Call ◽  
Self Assessment ◽  
Self Monitoring ◽  
Application Data ◽  
Participatory Surveillance ◽  
Electronic Questionnaires ◽  
Zip Code

Background We developed a self-assessment and participatory surveillance web application for coronavirus disease (COVID-19), which was launched in France in March 2020. Objective Our objective was to determine if self-reported symptoms could help monitor the dynamics of the COVID-19 outbreak in France. Methods Users were asked questions about underlying conditions, sociodemographic status, zip code, and COVID-19 symptoms. Depending on the symptoms reported and the presence of coexisting disorders, users were told to either stay at home, contact a general practitioner (GP), or call an emergency phone number. Data regarding COVID-19–related hospitalizations were retrieved from the Ministry of Health. Results As of March 29, 2020, the application was opened 4,126,789 times; 3,799,535 electronic questionnaires were filled out; and 2,477,174 users had at least one symptom. In total, 34.8% (n=1,322,361) reported no symptoms. The remaining users were directed to self-monitoring (n=858,878, 22.6%), GP visit or teleconsultation (n=1,033,922, 27.2%), or an emergency phone call (n=584,374, 15.4%). Emergency warning signs were reported by 39.1% of participants with anosmia, a loss of the sense of smell (n=127,586) versus 22.7% of participants without anosmia (n=1,597,289). Anosmia and fever and/or cough were correlated with hospitalizations for COVID-19 (Spearman correlation coefficients=0.87 and 0.82, respectively; P<.001 for both). Conclusions This study suggests that anosmia may be strongly associated with COVID-19 and its severity. Despite a lack of medical assessment and virological confirmation, self-checking application data could be a relevant tool to monitor outbreak trends. Trial Registration ClinicalTrials.gov NCT04331171; https://clinicaltrials.gov/ct2/show/NCT04331171

scholarly journals Epidemiological Observations on the Association Between Anosmia and COVID-19 Infection: Analysis of Data From a Self-Assessment Web Application (Preprint)

2020 ◽  
Author(s):  
Fabrice Denis ◽  
Simon Galmiche ◽  
Aurélien Dinh ◽  
Arnaud Fontanet ◽  
Arnaud Scherpereel ◽  
...  
Keyword(s):  
Web Application ◽  
Correlation Coefficients ◽  
Warning Signs ◽  
Phone Call ◽  
Self Assessment ◽  
Self Monitoring ◽  
Application Data ◽  
Participatory Surveillance ◽  
Electronic Questionnaires ◽  
Zip Code

BACKGROUND We developed a self-assessment and participatory surveillance web application for coronavirus disease (COVID-19), which was launched in France in March 2020. OBJECTIVE Our objective was to determine if self-reported symptoms could help monitor the dynamics of the COVID-19 outbreak in France. METHODS Users were asked questions about underlying conditions, sociodemographic status, zip code, and COVID-19 symptoms. Depending on the symptoms reported and the presence of coexisting disorders, users were told to either stay at home, contact a general practitioner (GP), or call an emergency phone number. Data regarding COVID-19–related hospitalizations were retrieved from the Ministry of Health. RESULTS As of March 29, 2020, the application was opened 4,126,789 times; 3,799,535 electronic questionnaires were filled out; and 2,477,174 users had at least one symptom. In total, 34.8% (n=1,322,361) reported no symptoms. The remaining users were directed to self-monitoring (n=858,878, 22.6%), GP visit or teleconsultation (n=1,033,922, 27.2%), or an emergency phone call (n=584,374, 15.4%). Emergency warning signs were reported by 39.1% of participants with anosmia, a loss of the sense of smell (n=127,586) versus 22.7% of participants without anosmia (n=1,597,289). Anosmia and fever and/or cough were correlated with hospitalizations for COVID-19 (Spearman correlation coefficients=0.87 and 0.82, respectively; <i>P</i>&lt;.001 for both). CONCLUSIONS This study suggests that anosmia may be strongly associated with COVID-19 and its severity. Despite a lack of medical assessment and virological confirmation, self-checking application data could be a relevant tool to monitor outbreak trends. CLINICALTRIAL ClinicalTrials.gov NCT04331171; https://clinicaltrials.gov/ct2/show/NCT04331171

scholarly journals Analysis of the sources of COVID-19 transmission in France by Self-assessment Web-application before and after the Partial Autumnal Lockdown: Observational Study (Preprint)

2021 ◽  
Author(s):  
Fabrice Denis ◽  
Anne-Lise Septans ◽  
Florian Le Goff ◽  
Stephan Jeanneau ◽  
François-Xavier Lescure
Keyword(s):  
Observational Study ◽  
Incubation Time ◽  
Web Application ◽  
Close Relative ◽  
Media Campaign ◽  
Self Assessment ◽  
National Media ◽  
Before And After ◽  
The Impact ◽  
Second Wave

BACKGROUND We developed a questionnaire on a web-application for COVID-19 circumstances of contamination analysis in France during the 2nd wave of pandemic. OBJECTIVE To analyze the impact on contaminations characteristics of the second partial lockdown in France to adapt health public restrictions to further pandemic surges. METHODS Between 12/15/2020 and 12/24/2020, after a national media campaign, users of sourcecovid.fr web-application were asked questions about their own or a close relative COVID-19 contamination after 8/15/2020 in France. Data of contamination’s circumstances were assessed and compared before and after the second partial lockdown which occurred on 10/25/2020 during the second wave of pandemic and was ongoing on 12/24/2020. RESULTS As of December 24, 2020, 441 000 connections on web-application were observed. 2218 questionnaires were assessable for analysis. 61.8% were sure of their contamination origin and 38.2% thought they knew it. The median age of users was 43.0 years (IQR 32 to 56), 50.7% were male. The median incubation time of the assessed cohort was 4.0 days (IQR 3 to 5). Private area (family and friends) was the main source of contamination (50.2%) followed by work colleagues: 27.7%. The main time of contamination of the day was the evening (35.3%) before the lockdown and was reduced to 18.2% after it (P<0.001). The person who transmitted the virus to the user before and after the lockdown was significantly different (P<0.001): a friend (29.0% vs 14.1%), a family close relative (23.1% vs 32.7%), a work colleague (23.9% vs 34.2%). The main location where the virus was transmitted to the users before and after lockdown was significantly different too (P<0.001), respectively: Home (21.3% vs 25.5%), at work (22.4% vs 29.6%), collective places (33.0% vs 15.0%), and care centers (4.4% vs 9.7%). CONCLUSIONS Modalities of transmissions significantly changed before and after the 2nd lockdown in France. The main sources of contaminations remained the private area and work colleagues. Work became the main location of contamination after lockdown whereas collective places contaminations were strongly reduced. CLINICALTRIAL ClinicalTrials.gov NCT04670003

scholarly journals Adapted version of the Pubertal Development Scale for use in Brazil

2019 ◽  
Vol 53 ◽  
pp. 56
Author(s):  
Sabine Pompéia ◽  
Gislaine De Almeida Valverde Zanini ◽  
Rafaella Sales de Freitas ◽  
Luanna Maristella Cabanal Inacio ◽  
Flávia Calanca da Silva ◽  
...  
Keyword(s):  
Large Scale ◽  
Pubertal Development ◽  
Correlation Coefficients ◽  
Scoring Systems ◽  
Cross Sectional Study ◽  
Clinical Staging ◽  
Adolescent Medicine ◽  
Self Assessment ◽  
Cross Sectional ◽  
Convenience Sample

OBJECTIVE: To determine whether scores in an adapted version of the self-assessment Pubertal Development Scale into Portuguese match those from the gold standard in pubertal development (Tanner scale). METHODS: This was a cross-sectional study with a convenience sample of 133 children and adolescents aged nine to 17 years (59 males; mean age of 13 years and six months, with standard deviation = 25 months). Youngsters completed the Pubertal Development Scale and were then examined by specialists in adolescent medicine. RESULTS: Exact absolute agreement of pubertal stages were modest, but significant associations between measures (correlation; intra-class correlation coefficients of consistency) showed that the Pubertal Development Scale adequately measures changes that map onto pubertal development determined by physical examination, on par with international publications. Furthermore, scores obtained from each Pubertal Development Scale question reflected adequate gonadal and adrenal events assessed by clinical ratings, mostly with medium/high effect sizes. Latent factors obtained from scores on all Pubertal Development Scale questions had excellent fit indices in Confirmatory Factor Analyses and correlated with Tanner staging. CONCLUSIONS: We conclude that self-assessment of body changes by youngsters using the Portuguese version of the Pubertal Development Scale is useful when estimates of pubertal progression are sufficient, and exact agreement with clinical staging is not necessary. The Pubertal Development Scale is, therefore, a reliable instrument for use in large-scale studies in Brazil that aim at investigating adolescent health related to pubertal developmental. The translated version and scoring systems are provided.

scholarly journals Clinical validation of a novel web-application for remote assessment of distance visual acuity

Eye ◽  
2021 ◽  
Author(s):  
Arun James Thirunavukarasu ◽  
Deborah Mullinger ◽  
Remi Mohan Rufus-Toye ◽  
Sarah Farrell ◽  
Louise E. Allen
Keyword(s):  
Visual Acuity ◽  
Data Storage ◽  
Web Application ◽  
Intraclass Correlation ◽  
Home Monitoring ◽  
Correlation Coefficients ◽  
Remote Consultation ◽  
Self Assessment ◽  
Distance Visual Acuity ◽  
Remote Assessment

Abstract Background/Objectives Ophthalmic disorders cause 8% of hospital clinic attendances, the highest of any specialty. The fundamental need for a distance visual acuity (VA) measurement constrains remote consultation. A web-application, DigiVis, facilitates self-assessment of VA using two internet-connected devices. This prospective validation study aimed to establish its accuracy, reliability, usability and acceptability. Subjects/Methods In total, 120 patients aged 5–87 years (median = 27) self-tested their vision twice using DigiVis in addition to their standard clinical assessment. Eyes with VA worse than +0.80 logMAR were excluded. Accuracy and test-retest (TRT) variability were compared using Bland–Altman analysis and intraclass correlation coefficients (ICC). Patient feedback was analysed. Results Bias between VA tests was insignificant at −0.001 (95% CI −0.017 to 0.015) logMAR. The upper limit of agreement (LOA) was 0.173 (95% CI 0.146 to 0.201) and the lower LOA −0.175 (95% CI −0.202 to −0.147) logMAR. The ICC was 0.818 (95% CI 0.748 to 0.869). DigiVis TRT mean bias was similarly insignificant, at 0.001 (95% CI −0.011 to 0.013) logMAR, the upper LOA was 0.124 (95% CI 0.103 to 0.144) and the lower LOA −0.121 (95% CI −0.142 to −0.101) logMAR. The ICC was 0.922 (95% CI 0.887 to 0.946). 95% of subjects were willing to use DigiVis to monitor vision at home. Conclusions Self-tested distance VA using DigiVis is accurate, reliable and well accepted by patients. The app has potential to facilitate home monitoring, triage and remote consultation but widescale implementation will require integration with NHS databases and secure patient data storage.

Detection of 20 Phthalate Esters in Different Kinds of Food Packaging Materials by GC-MS/MS with Five Internal Standards

2019 ◽  
Vol 102 (1) ◽  
pp. 255-261 ◽  
Author(s):  
Ji-cai Fan ◽  
Quan Jin ◽  
Hua-li He ◽  
Ren Ren ◽  
Shu-ting Wang
Keyword(s):  
Food Packaging ◽  
Large Scale ◽  
Phthalate Esters ◽  
Correlation Coefficients ◽  
Packaging Materials ◽  
Purification Step ◽  
Internal Standards ◽  
Extraction Solvent ◽  
Food Packaging Materials ◽  
Relative Standard

Abstract Background: Phthalate esters (PAEs) are a group of chemical compounds widely used as plasticizers to increase the flexibility of plastics that are used in the manufacturing of kitchen utensils and food containers. Objective: In this study, a simple, rapid, and sensitive method for the determination of 20 PAEs in different kinds of food packaging materials has been developed. Methods: Samples injected with five internal standards were extracted with acetonitrile saturated with n-hexane and then detected by GC-MS/MS without a purification step. Results: The standard calibration curves were linear for all analytes over the concentration range of 5–500 μg/L, and the correlation coefficients ranged from 0.9913 to 0.9999. The LODs and LOQs were in the ranges of 1.7–62.5 and 5.5–208.3 μg/kg, respectively. The accuracy of this method was evaluated by measuring the recovery from spiked samples. The recoveries of all 20 phthalates from samples spiked at three different concentrations were measured, and the recovery was in the range of 82.1–110.8% and the relative standard deviation range of recovery result (n = 6) was 0.3–9.7%. Conclusions: The method presented here is simple, rapid, and sensitive and can be applied to large-scale detection of PAEs in plastic materials. Highlights: Instead of only one solvent, acetonitrile saturated with n-hexane was used as the extraction solvent. Samples were pretreated without a purification step. Five internal standards were used for quantitative determination.

scholarly journals Cross-Scale Precipitation Variability in a Semiarid Catchment Area on the Western Slopes of the Central Andes

2018 ◽  
Vol 57 (3) ◽  
pp. 675-694 ◽  
Author(s):  
Katja Trachte ◽  
Jochen Seidel ◽  
Rafael Figueroa ◽  
Marco Otto ◽  
Joerg Bendix
Keyword(s):  
Cluster Analysis ◽  
Catchment Area ◽  
Altitudinal Gradient ◽  
Large Scale ◽  
Wrf Model ◽  
Correlation Coefficients ◽  
Elevational Gradient ◽  
Central Andes ◽  
Precipitation Variability ◽  
Precipitation Regimes

AbstractSpatiotemporal precipitation patterns were investigated on the western slopes of the central Andes Mountains by applying EOF and cluster analysis as well as the Weather Research and Forecasting (WRF) Model. In the semiarid catchment area in the highlands of Lima, Peru, the precipitation is assumed to be a cross-scale interplay of large-scale dynamics, varying sea surface temperatures (SSTs), and breeze-dominated slope flows. The EOF analysis was used to encompass and elucidate the upper-level circulation patterns dominating the transport of moisture. To delineate local precipitation regimes, a partitioning cluster analysis was carried out, which additionally should illustrate local effects such as the altitudinal gradient of the Andes. The results demonstrated that especially during the transition to the dry season, synoptic-scale circulation aloft controls the precipitation (correlation coefficients between 0.6 and 0.9), whereas in the remaining seasons the slope breezes due to the altitudinal gradient mainly determine the precipitation behavior. Further analysis with regard to the spatiotemporal precipitation variability revealed an inversion of the precipitation distribution along the elevational gradient within the study area, mainly during February (29%) and March (35%), that showed correlations with coastal SST patterns ranging between 0.56 and 0.67. WRF simulations of the underlying mechanisms disclosed that the large-scale circulation influences the thermally induced upslope flows while the strength of southeastern low-level winds related to the coastal SSTs caused a blocking of easterlies in the middle troposphere through a reduced anticyclonic effect. This interplay enables the generation of precipitation in the usually drier environment at lower elevations, which leads to a decrease in rainfall with increasing elevation.

scholarly journals Expert and self-assessment of lifetime symptoms and diagnosis of major depressive disorder in large-scale genetic studies in the general population

2017 ◽  
Vol 27 (5) ◽  
pp. 187-196 ◽  
Author(s):  
Jessica Martin ◽  
Fabian Streit ◽  
Jens Treutlein ◽  
Maren Lang ◽  
Josef Frank ◽  
...  
Keyword(s):  
Major Depressive Disorder ◽  
General Population ◽  
Depressive Disorder ◽  
Large Scale ◽  
Self Assessment ◽  
Major Depressive ◽  
Genetic Studies

Cross-contamination in molecular laboratories: A challenge to COVID-19 testing in Bangladesh

2021 ◽  
Vol 2 (5) ◽  
Author(s):  
Mohammad Jahidur Rahman Khan ◽  
◽  
Selim Reza ◽  
Farzana Mim ◽  
Md Abdullah Rumman ◽  
...  
Keyword(s):  
Public Health ◽  
Large Scale ◽  
Diagnostic Testing ◽  
Diagnostic Errors ◽  
Laboratory Diagnosis ◽  
Cross Contamination ◽  
Rt Pcr ◽  
Public Health Response ◽  
Surveillance Programs ◽  
The Government

Rapid and accurate laboratory diagnosis of SARS-CoV-2 infection is crucial for the management of COVID-19 patients and control of the spread of the virus. At the start of the COVID-19 pandemic, Bangladesh had only one government molecular laboratory where real-time RT-PCR will be performed to diagnose SARS-CoV-2 infection. With the increasing number of suspected cases requiring confirmation diagnostic testing, there was a requirement to quickly expand capacity for large-scale testing. The government of Bangladesh established over 100 molecular laboratories within one year to test COVID-19. To fulfil the requirement for expanded testing, the government was compelled to recruit laboratory employees with inadequate experience, technical knowledge, and skills in molecular assays, particularly in processing specimens, interpreting results, recognizing errors, and troubleshooting. As a result, the risk of diagnostic errors, such as cross-contamination, is increased, as is that the risk of false-positive results, which might risk the patient’s health and undermine the efficacy of public health policies, public health response, surveillance programs, and restrictive measures aimed toward containing the outbreak. This review article aims to explain different sources of crosscontamination in the COVID-19 RT-PCR laboratories and the way to forestall them in efficient and practical ways.

Scale-to-scale anisotropy in homogeneous turbulence

2017 ◽  
Vol 827 ◽  
pp. 250-284 ◽  
Author(s):  
Douglas W. Carter ◽  
Filippo Coletti
Keyword(s):  
Large Scale ◽  
Velocity Structure ◽  
Longitudinal Velocity ◽  
Reynolds Numbers ◽  
Homogeneous Turbulence ◽  
Mean Flow ◽  
Spatially Correlated ◽  
Air Jets ◽  
Image Velocimetry ◽  
Definition Of

We experimentally investigate scale-to-scale anisotropy from the integral to the dissipative scales in homogeneous turbulence. We employ an apparatus in which two facing arrays of randomly actuated air jets generate turbulence with negligible mean flow and shear, over a volume several times larger than the energy-containing eddy size. The Reynolds number based on the Taylor microscale is varied in the range$Re_{\unicode[STIX]{x1D706}}\approx 300{-}500$, while the axial-to-radial ratio of the root mean square velocity fluctuations ranges between 1.38 and 1.72. Two velocity components are measured by particle image velocimetry at varying resolutions, capturing from the integral to the Kolmogorov scales and yielding statistics up to sixth order. Over the inertial range, the scaling exponents of the velocity structure functions are found to differ not only between the longitudinal and transverse components, but also between the axial and radial directions of separation. At the dissipative scales, the moments of the velocity gradients indicate that departure from isotropy is, at the present Reynolds numbers, significant and more pronounced for stronger large-scale anisotropy. The generalized flatness factors of the longitudinal velocity differences tend towards isotropy as the separation is reduced from the inertial to the near-dissipative scales (down to about$10\unicode[STIX]{x1D702}$,$\unicode[STIX]{x1D702}$being the Kolmogorov length), but become more anisotropic for even smaller scales which are characterized by high intermittency. At the large scales, the direction of turbulence forcing is associated with a larger integral length, defined as the distance over which the velocity component in a given direction is spatially correlated. Because of anisotropy, the definition of the integral length is not trivial and may lead to dissimilar conclusions on the qualitative behaviour of the large scales and on the quantitative values of the normalized dissipation. Alternative definitions of these quantities are proposed to account for the anisotropy. Overall, these results highlight the importance of evaluating both the different velocity components and the different spatial directions across all scales of the flow.

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