Basic Epidemiological Parameters at the end of the 5th month of the COVID-19 Outbreak

AbstractA better understanding of how the COVID-19 pandemic responds to social distancing efforts is required for the control of future outbreaks and to calibrate partial lock-downs. We present quantitative relationships between key parameters characterizing the COVID-19 epidemiology and social distancing efforts of nine selected European countries. Epidemiological parameters were extracted from the number of daily deaths data, while mitigation efforts are estimated from mobile phone tracking data. The decrease of the basic reproductive number ($$R_0$$ R 0 ) as well as the duration of the initial exponential expansion phase of the epidemic strongly correlates with the magnitude of mobility reduction. Utilizing these relationships we decipher the relative impact of the timing and the extent of social distancing on the total death burden of the pandemic.

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The implications of subretinal fluid in pachychoroid neovasculopathy

Scientific Reports ◽

10.1038/s41598-021-83650-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Geun Woo Lee ◽

Hyeon Cheol Roh ◽

Se Woong Kang ◽

A. Young Kim ◽

Hoon Noh ◽

...

Keyword(s):

Central Serous Chorioretinopathy ◽

Polypoidal Choroidal Vasculopathy ◽

Multimodal Imaging ◽

Optical Coherence Tomography Angiography ◽

Subretinal Fluid ◽

Longitudinal Changes ◽

History Of ◽

Pachychoroid Neovasculopathy ◽

Choroidal Vasculopathy ◽

Epidemiological Parameters

AbstractThis study aimed to identify the clinical characteristics and longitudinal changes in exudative pachychoroid neovasculopathy (PNV) and non-exudative PNV. This retrospective cohort study involved 81 eyes of PNV diagnosed by multimodal imaging including optical coherence tomography angiography. At baseline, they were divided into exudative PNV group and non-exudative PNV group depending on the presence of subretinal fluid. The clinical features of both groups and the longitudinal changes were investigated and compared. There were 55 eyes with non-exudative PNV and 26 eyes with exudative PNV. Individuals with non-exudative PNV were older, more frequently asymptomatic and had a higher prevalence of polypoidal choroidal vasculopathy in the opposite eye (all P’s < 0.05). Whereas individuals with exudative PNV showed thicker choroid and more frequent history of central serous chorioretinopathy (all P’s < 0.001). During about 12 months of longitudinal observation, the transformation into polypoidal choroidal vasculopathy was noted in 4 eyes of non-exudative PNV group, whereas in none of the exudative PNV group. Exudative PNV and non-exudative PNV seem to be separate entities with different epidemiological parameters. Non-exudative PNV, which is frequently found without symptoms at an older age, is suspected to be the significant precursor lesion of polypoidal choroidal vasculopathy. In contrast, exudative PNV may share the same pathophysiology as central serous chorioretinopathy.

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General Epidemiological Parameters of Viral Hepatitis A, B, C, and E in Six Regions of China: A Cross-Sectional Study in 2007

PLoS ONE ◽

10.1371/journal.pone.0008467 ◽

2009 ◽

Vol 4 (12) ◽

pp. e8467 ◽

Cited By ~ 73

Author(s):

Jian Lu ◽

Yongdong Zhou ◽

Xiaojing Lin ◽

Yongzhen Jiang ◽

Ruiguang Tian ◽

...

Keyword(s):

Viral Hepatitis ◽

Hepatitis A ◽

Cross Sectional Study ◽

Sectional Study ◽

Cross Sectional ◽

Viral Hepatitis A ◽

Epidemiological Parameters

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Inferring R 0 in emerging epidemics—the effect of common population structure is small

Journal of The Royal Society Interface ◽

10.1098/rsif.2016.0288 ◽

2016 ◽

Vol 13 (121) ◽

pp. 20160288 ◽

Cited By ~ 14

Author(s):

Pieter Trapman ◽

Frank Ball ◽

Jean-Stéphane Dhersin ◽

Viet Chi Tran ◽

Jacco Wallinga ◽

...

Keyword(s):

Infectious Disease ◽

Population Structure ◽

Robust Control ◽

Reproduction Number ◽

Contact Structures ◽

Emerging Infections ◽

Control Effort ◽

Large Outbreak ◽

Epidemiological Parameters ◽

The Basic Reproduction Number

When controlling an emerging outbreak of an infectious disease, it is essential to know the key epidemiological parameters, such as the basic reproduction number R 0 and the control effort required to prevent a large outbreak. These parameters are estimated from the observed incidence of new cases and information about the infectious contact structures of the population in which the disease spreads. However, the relevant infectious contact structures for new, emerging infections are often unknown or hard to obtain. Here, we show that, for many common true underlying heterogeneous contact structures, the simplification to neglect such structures and instead assume that all contacts are made homogeneously in the whole population results in conservative estimates for R 0 and the required control effort. This means that robust control policies can be planned during the early stages of an outbreak, using such conservative estimates of the required control effort.

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Relationship among epidemiological parameters of six childhood infections in a non-immunized Brazilian community

Memórias do Instituto Oswaldo Cruz ◽

10.1590/s0074-02762009000600013 ◽

2009 ◽

Vol 104 (6) ◽

pp. 897-900 ◽

Cited By ~ 8

Author(s):

Marcos Amaku ◽

Raymundo Soares Azevedo ◽

Ruy Morgado de Castro ◽

Eduardo Massad ◽

Francisco Antonio Bezerra Coutinho

Keyword(s):

Childhood Infections ◽

Epidemiological Parameters

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Ewing sarcoma: Analysis of epidemiological parameters and their relation to clinical characteristics

Srpski arhiv za celokupno lekarstvo ◽

10.2298/sarh0608310s ◽

2006 ◽

Vol 134 (7-8) ◽

pp. 310-314

Author(s):

Vladan Stevanovic ◽

Zoran Vukasinovic ◽

Dusko Spasovski

Keyword(s):

Ewing Sarcoma ◽

Orthopedic Surgery ◽

Clinical Characteristics ◽

Clinical Findings ◽

Tumor Localization ◽

Age Group ◽

Serious Illness ◽

Success Of Treatment ◽

Epidemiologic Features ◽

Epidemiological Parameters

The purpose of this investigation was to evaluate epidemiologic features of Ewing sarcoma in children treated in the Institute for Orthopedic Surgery "Banjica", as well as to establish relation of these features to clinical findings. Study involved 78 patients treated over 20-year period (1980-2000). Analysis included standard epidemiologic data (age, sex, tumor localization) and diagnostic clinical features on presentation (major symptoms, time elapsed between presentation and diagnosis, presence of metastases). Most of the patients were in the age group of 15-18 years (50.0%), predominantly males. In general, the results of our study were consistent with data reported in literature. Nevertheless, this investigation revealed slightly higher incidence in patients younger than four years of age (5.1%); localization on the upper extremity was found to be more frequent (upper to lower extremity ratio was nearly 3:1 in our study), and the time lost between presentation and diagnosis was markedly reduced (average time elapsed between presentation and diagnosis was 2.5 months). The results of our study may improve efficiency and success of treatment, thus providing the basis of better prognosis in management of such a serious illness.

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Early epidemiological assessment of the transmission potential and virulence of coronavirus disease 2019 (COVID-19) in Wuhan City: China, January-February, 2020

10.1101/2020.02.12.20022434 ◽

2020 ◽

Cited By ~ 40

Author(s):

Kenji Mizumoto ◽

Katsushi Kagaya ◽

Gerardo Chowell

Keyword(s):

Basic Reproduction Number ◽

Reproduction Number ◽

Public Health Intervention ◽

Ecological Modelling ◽

The Novel ◽

Wuhan City ◽

Transmission Potential ◽

The World ◽

Novel Coronavirus ◽

Epidemiological Parameters

AbstractBackgroundSince the first cluster of cases was identified in Wuhan City, China, in December, 2019, coronavirus disease 2019 (COVID-19) rapidly spread around the world. Despite the scarcity of publicly available data, scientists around the world have made strides in estimating the magnitude of the epidemic, the basic reproduction number, and transmission patterns. Accumulating evidence suggests that a substantial fraction of the infected individuals with the novel coronavirus show little if any symptoms, which highlights the need to reassess the transmission potential of this emerging disease. In this study, we derive estimates of the transmissibility and virulence of COVID-19 in Wuhan City, China, by reconstructing the underlying transmission dynamics using multiple data sources.MethodsWe employ statistical methods and publicly available epidemiological datasets to jointly derive estimates of transmissibility and severity associated with the novel coronavirus. For this purpose, the daily series of laboratory–confirmed COVID-19 cases and deaths in Wuhan City together with epidemiological data of Japanese repatriated from Wuhan City on board government–chartered flights were integrated into our analysis.ResultsOur posterior estimates of basic reproduction number (R) in Wuhan City, China in 2019–2020 reached values at 3.49 (95%CrI: 3.39–3.62) with a mean serial interval of 6.0 days, and the enhanced public health intervention after January 23rd in 2020 was associated with a significantly reduced R at 0.84 (95%CrI: 0.81–0.88), with the total number of infections (i.e. cumulative infections) estimated at 1906634 (95%CrI: 1373500–2651124) in Wuhan City, elevating the overall proportion of infected individuals to 19.1% (95%CrI: 13.5–26.6%). We also estimated the most recent crude infection fatality ratio (IFR) and time–delay adjusted IFR at 0.04% (95% CrI: 0.03%–0.06%) and 0.12% (95%CrI: 0.08–0.17%), respectively, estimates that are several orders of magnitude smaller than the crude CFR estimated at 4.06%ConclusionsWe have estimated key epidemiological parameters of the transmissibility and virulence of COVID-19 in Wuhan, China during January-February, 2020 using an ecological modelling approach. The power of this approach lies in the ability to infer epidemiological parameters with quantified uncertainty from partial observations collected by surveillance systems.

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Illuminance affects epidemiological parameters of banana Yellow Sigatoka in Brazil

10.1101/828848 ◽

2019 ◽

Author(s):

Djalma M. Santana-Filho ◽

Milene C. da Silva ◽

Jorge T. de Souza ◽

Zilton J. M. Cordeiro ◽

Hermínio S. Rocha ◽

...

Keyword(s):

Logistic Regression ◽

Survival Analysis ◽

Cropping Systems ◽

Leaf Age ◽

Cropping System ◽

Black Sigatoka ◽

Light Interference ◽

Leaf Spots ◽

Leaf Necrosis ◽

Epidemiological Parameters

ABSTRACTThe Sigatoka leaf spots are among the most important banana diseases. Although less damaging than black sigatoka, yellow sigatoka (Pseudocercospora musae) still prevails in some regions. This study aimed at testing the hypothesis of light interference in monocyclic parameters of yellow sigatoka epidemics. Grande Naine plantlets kept under contrasting shading conditions had their leaves 1 and 2 inoculated. Evaluations were performed for 60 days. For each inoculated leaf, the time until symptom onset (incubation), presence of infectious lesions (latency), and disease severity (extensive leaf necrosis) according to Stover’s scale modify per Gauhl (1994), called here only Stover’s scale, were registered. Logistic regression was used to assess the relative occurrence risk and survival analysis was used to check the effects of variables on relevant epidemiological parameters. The risks of sporulation and of reaching high severities were lower for plants kept under shading regardless of the acclimation conditions and no effect of leaf age was detected. The logistic regression showed symptoms appearing in both conditions (p=0,85), but have significance difference in occurrence of latent lesions (p=0,013) and necrosis (p<0,0001). The necrosis risk in non-shaded environment arrived 66%. The survival analysis showed significance difference in the time to appear the symptom evaluated in all tested variables (p<0,0001) in function of the cropping system. Lower illuminance negatively affected the incubation, latency and infectious periods, and severity. A shaded system could be tested to produce organic bananas in areas of high risk of occurrence of Yellow sigatoka disease.Significance and Impact of the StudyYellow Sigatoka (Pseudocercospora musae) is a banana disease that can cause severe damage if left uncontrolled. Its control is based mostly on fungicides.Our results show that shading downregulates the epidemiological parameters of that disease such as incubation, latent and infectious periods, and symptom’s severity. These results can be the basis for testing alternative cropping systems and producing organic bananas.

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CLINICAL AND EPIDEMIOLOGICAL ANALYSIS OF MALIGNANT NEOPLASMS OF THE ABDOMINAL ORGANS

Clinical & experimental pathology ◽

10.24061/1727-4338.xix.4.74.2020.5 ◽

2021 ◽

Vol 19 (4) ◽

Author(s):

I.A. Malishevsky

Keyword(s):

Developmental Stages ◽

Abdominal Cavity ◽

Malignant Neoplasms ◽

Newly Diagnosed ◽

Epidemiological Analysis ◽

Software Packages ◽

Abdominal Organs ◽

Microsoft Office ◽

Epidemiological Characteristics ◽

Epidemiological Parameters

Purpose – to determine the statistical and epidemiological parameters of malignantneoplasms of the abdominal cavity organs.Material and methods. The study was carried out on the basis of the Chernivtsi RegionalClinical Oncological Dispensary and covers observation materials during 2019 andstatistical reporting concerning 21259 patients with tumors of various localization. The calculation of indices was carried out using software packages MS Access and MS Excelbased on the Microsoft Office medium.Results. Neoplasms of the abdominal organs account for 32.4%-37.1% of the totalnumber of neoplasms of various localization. The distribution of patients with malignantdiseases of the abdominal organs by developmental stages is relatively uniform, despitesignificant differences in various localizations of neoplasmsConclusions. Malignant neoplasms of the abdominal organs account for 32.4%(registered) and 37.1% of the newly diagnosed of the total number of tumors of variouslocalization, indicating the importance of further research. A significant part of tumors ofthe abdominal cavity organs are diagnosed in the late (III-IV) stages of the pathologicalprocess development (up to 94.7% in the liver and intrahepatic biliary tract). Therevealed significant differences in clinical and epidemiological characteristics requirefurther research.

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GLOBAL SPREAD OF INFECTIOUS DISEASES

Journal of Biological System ◽

10.1142/s0218339004001154 ◽

2004 ◽

Vol 12 (03) ◽

pp. 289-300 ◽

Cited By ~ 12

Author(s):

S. HSU ◽

A. ZEE

Keyword(s):

Public Health ◽

Infectious Diseases ◽

Human Mobility ◽

Air Travel ◽

Peak Number ◽

Public Health Infrastructure ◽

Health Infrastructure ◽

Global Spread ◽

Epidemiological Parameters ◽

Simple Models

We develop simple models for the global spread of infectious diseases, emphasizing human mobility via air travel and the variation of public health infrastructure from region to region. We derive formulas relating the total and peak number of infections in two countries to the rate of travel between them and their respective epidemiological parameters.

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