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  1. Article: SEIR modeling of the COVID-19 and its dynamics.

    He, Shaobo / Peng, Yuexi / Sun, Kehui

    Nonlinear dynamics

    2020  Volume 101, Issue 3, Page(s) 1667–1680

    Abstract: ... strategies of the COVID-19 based on the structure and parameters of the proposed model. ... In this paper, a SEIR epidemic model for the COVID-19 is built according to some general control ... 19 epidemic situation. Moreover, by introducing the seasonality and stochastic infection ...

    Abstract In this paper, a SEIR epidemic model for the COVID-19 is built according to some general control strategies, such as hospital, quarantine and external input. Based on the data of Hubei province, the particle swarm optimization (PSO) algorithm is applied to estimate the parameters of the system. We found that the parameters of the proposed SEIR model are different for different scenarios. Then, the model is employed to show the evolution of the epidemic in Hubei province, which shows that it can be used to forecast COVID-19 epidemic situation. Moreover, by introducing the seasonality and stochastic infection the parameters, nonlinear dynamics including chaos are found in the system. Finally, we discussed the control strategies of the COVID-19 based on the structure and parameters of the proposed model.
    Keywords covid19
    Language English
    Publishing date 2020-06-18
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 2012600-1
    ISSN 1573-269X ; 0924-090X
    ISSN (online) 1573-269X
    ISSN 0924-090X
    DOI 10.1007/s11071-020-05743-y
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: SEIR modeling of the COVID-19 and its dynamics

    He, Shaobo / Peng, Yuexi / Sun, Kehui

    Nonlinear Dynamics ; ISSN 0924-090X 1573-269X

    2020  

    Keywords Control and Systems Engineering ; Mechanical Engineering ; Electrical and Electronic Engineering ; Applied Mathematics ; Ocean Engineering ; Aerospace Engineering ; covid19
    Language English
    Publisher Springer Science and Business Media LLC
    Publishing country us
    Document type Article ; Online
    DOI 10.1007/s11071-020-05743-y
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article: SEIR modeling of the COVID-19 and its dynamics

    He, Shaobo / Peng, Yuexi / Sun, Kehui

    Nonlinear Dyn

    Abstract: ... strategies of the COVID-19 based on the structure and parameters of the proposed model. ... In this paper, a SEIR epidemic model for the COVID-19 is built according to some general control ... 19 epidemic situation. Moreover, by introducing the seasonality and stochastic infection ...

    Abstract In this paper, a SEIR epidemic model for the COVID-19 is built according to some general control strategies, such as hospital, quarantine and external input. Based on the data of Hubei province, the particle swarm optimization (PSO) algorithm is applied to estimate the parameters of the system. We found that the parameters of the proposed SEIR model are different for different scenarios. Then, the model is employed to show the evolution of the epidemic in Hubei province, which shows that it can be used to forecast COVID-19 epidemic situation. Moreover, by introducing the seasonality and stochastic infection the parameters, nonlinear dynamics including chaos are found in the system. Finally, we discussed the control strategies of the COVID-19 based on the structure and parameters of the proposed model.
    Keywords covid19
    Publisher WHO
    Document type Article
    Note WHO #Covidence: #603584
    Database COVID19

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  4. Book ; Online: ECheynet/SEIR

    E. Cheynet

    Generalized SEIR Epidemic Model (fitting and computation)

    2020  

    Abstract: ... _region.mlx, which uses data collected by the Johns Hopkins University for the COVID-19 epidemy [3 ... Hopkins University for the COVID-19 epidemy [3] for a coutnry. One file "ItalianRegions.mlx" written ... by Matteo Secli (https://github.com/matteosecli), that collects the updated data of the COVID-19 pandemic ...

    Abstract Description A generalized SEIR model with seven states [2] is numerically implemented in Matlab. The implementation is done from scratch except for the fitting, that relies on the function "lsqcurvfit". The present submission includes several majors difference with respect to ref. [2]. Among them is the expression of the death rate and recovery rate, which are analytical and empirical functions of the time. The idea behind this time-dependency as that the death and recovery rate should converge toward a constant value as the time increases. If the death rate is kept constant, the number of death may be overestimated. Births and natural death are not modelled here. This means that the total population, including the number of deceased cases, is kept constant. Note that ref. [2] is a preprint that is not peer-reviewed and I am not qualified enough to judge the quality of the paper. Content The present submission contains: A function SEIQRDP.m that is used to simulate the time histories of the infectious, recovered and dead cases (among others) A function fit_SEIQRDP.m that estimates the eight parameters used in SEIQRDP.m in the least square sense. One example file Documentation.mlx, which presents the numerical implementation. One example file Example_province_region.mlx, which uses data collected by the Johns Hopkins University for the COVID-19 epidemy [3] for Hubei province (China). One example file Example_Country.mlx, which uses data collected by the Johns Hopkins University for the COVID-19 epidemy [3] for a coutnry. One file "ItalianRegions.mlx" written by Matteo Secli (https://github.com/matteosecli) that I have modified for a slightly more robust fitting. One file "FrenchRegions.mlx", which gives another example for Data collected in France. The data quality is not as good as expected, so the fitting is unlikely to provide reliable parameter estimates. One example file ChineseProvinces.mlx, which illustrates how the function fit_SEIQRDP.m is used in a for loop to be fitted to the data [3] from the different Chinese provinces. One example "uncertaintiesIssues.mlx", which illustrates the danger of fitting limited data sets. One example "Example_US_cities.mlx" that illustrates the fitting when "recovered" data are not available. One example simulateMultipleWaves,mlx that illustrates the fitting for multiple epidemic waves. One function getDataCOVID, which read from [3] the data collected by Johns Hopkins University. One function getDataCOVID_ITA written by Matteo Secli (https://github.com/matteosecli), that collects the updated data of the COVID-19 pandemic in Italy from the Italian government [4] One function getDataCOVID_FRA that collects the updated data in France from [5] One function getDataCOVID_US that collects the updated data in the USA from [3] One function checkRates.m that plots the fitted and computed death and recovery rates (quality check) One function getMultipleWaves.m that simulate and fit the SEIRQDP model to the situations where multiple epidemic waves are detected. Any question, comment or suggestion is welcome. References [1] https://en.wikipedia.org/wiki/Compartmental_models_in_epidemiology#Bio-mathematical_deterministic_treatment_of_the_SIR_model [2] Peng, L., Yang, W., Zhang, D., Zhuge, C., & Hong, L. (2020). Epidemic analysis of COVID-19 in China by dynamical modeling. arXiv preprint arXiv:2002.06563. [3] https://github.com/CSSEGISandData/COVID-19 [4] https://github.com/pcm-dpc/COVID-19 [5] https://github.com/cedricguadalupe/FRANCE-COVID-19

    The LiveScript files can be read at: https://se.mathworks.com/matlabcentral/fileexchange/74545-generalized-seir-epidemic-model-fitting-and-computation
    Keywords covid ; SEIR ; SEIQRDP ; epidemic model ; Matlab ; Fitting ; dynamic modelling ; covid19
    Subject code 519
    Publishing date 2020-05-10
    Publishing country eu
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Delay-differential SEIR modeling for improved modelling of infection dynamics.

    Kiselev, I N / Akberdin, I R / Kolpakov, F A

    Scientific reports

    2023  Volume 13, Issue 1, Page(s) 13439

    Abstract: ... of the delay-based model of the COVID-19 pandemic in Germany and France. The model takes into account testing ... only to Covid-19 but also to the study of other infectious diseases. We utilized it in the development ... to reproduce observable dynamics of an infection such as the incubation period or progression of the disease's ...

    Abstract SEIR (Susceptible-Exposed-Infected-Recovered) approach is a classic modeling method that is frequently used to study infectious diseases. However, in the vast majority of such models transitions from one population group to another are described using the mass-action law. That causes inability to reproduce observable dynamics of an infection such as the incubation period or progression of the disease's symptoms. In this paper, we propose a new approach to simulate the epidemic dynamics based on a system of differential equations with time delays and instant transitions to approximate durations of transition processes more correctly and make model parameters more clear. The suggested approach can be applied not only to Covid-19 but also to the study of other infectious diseases. We utilized it in the development of the delay-based model of the COVID-19 pandemic in Germany and France. The model takes into account testing of different population groups, symptoms progression from mild to critical, vaccination, duration of protective immunity and new virus strains. The stringency index was used as a generalized characteristic of the non-pharmaceutical government interventions in corresponding countries to contain the virus spread. The parameter identifiability analysis demonstrated that the presented modeling approach enables to significantly reduce the number of parameters and make them more identifiable. Both models are publicly available.
    MeSH term(s) Humans ; COVID-19/epidemiology ; Pandemics/prevention & control ; France ; Germany ; Communicable Diseases/epidemiology
    Language English
    Publishing date 2023-08-18
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-023-40008-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Analysis of the second wave of COVID-19 in India based on SEIR model.

    Gopal, R / Chandrasekar, V K / Lakshmanan, M

    The European physical journal. Special topics

    2022  , Page(s) 1–8

    Abstract: ... SEIR) dynamic modeling of the epidemic evolution of COVID-19 in India with the help of appropriate ... our analysis to estimate and analyze the number of infected individuals during the second wave of COVID-19 ... India was under a grave threat from the second wave of the COVID-19 pandemic particularly ...

    Abstract India was under a grave threat from the second wave of the COVID-19 pandemic particularly in the beginning of May 2021. The situation appeared rather gloomy as the number of infected individuals/active cases had increased alarmingly during the months of May and June 2021 compared to the first wave peak. Indian government/state governments have been implementing various control measures such as lockdowns, setting up new hospitals, and putting travel restrictions at various stages to lighten the virus spread from the initial outbreak of the pandemic. Recently, we have studied the susceptible-exposed-infectious-removed (SEIR) dynamic modeling of the epidemic evolution of COVID-19 in India with the help of appropriate parameters quantifying the various governmental actions and the intensity of individual reactions. Our analysis had predicted the scenario of the first wave quite well. In this present article, we extend our analysis to estimate and analyze the number of infected individuals during the second wave of COVID-19 in India with the help of the above SEIR model. Our findings show that the people's individual effort along with governmental actions such as implementations of curfews and accelerated vaccine strategy are the most important factors to control the pandemic in the present situation and in the future.
    Language English
    Publishing date 2022-01-13
    Publishing country France
    Document type Journal Article
    ZDB-ID 2267176-6
    ISSN 1951-6401 ; 1951-6355
    ISSN (online) 1951-6401
    ISSN 1951-6355
    DOI 10.1140/epjs/s11734-022-00426-8
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Analysis and prediction of improved SEIR transmission dynamics model: taking the second outbreak of COVID-19 in Italy as an example.

    Lu, Ming / Zheng, Xu-Yang / Jia, Wei-Nan / Tian, Chun-Zhi

    Frontiers in public health

    2023  Volume 11, Page(s) 1223039

    Abstract: ... the significance of implementing anti-epidemic preventive measures in COVID-19 modeling. ... This study aimed to predict the transmission trajectory of the 2019 Corona Virus Disease (COVID-19 ... we consider the second outbreak of COVID-19 in Italy as a case study, which occurred in August 2020. We divide ...

    Abstract This study aimed to predict the transmission trajectory of the 2019 Corona Virus Disease (COVID-19) and analyze the impact of preventive measures on the spread of the epidemic. Considering that tracking a long-term epidemic trajectory requires explanatory modeling with more complexities than short-term predictions, an improved Susceptible-Exposed-Infected-Removed (SEIR) transmission dynamic model is established. The model depends on defining various parameters that describe both the virus and the population under study. However, it is likely that several of these parameters will exhibit significant variations among different states. Therefore, regression algorithms and heuristic algorithms were developed to effectively adapt the population-dependent parameters and ensure accurate fitting of the SEIR model to data for any specific state. In this study, we consider the second outbreak of COVID-19 in Italy as a case study, which occurred in August 2020. We divide the epidemic data from February to September of the same year into two distinct stages for analysis. The numerical results demonstrate that the improved SEIR model effectively simulates and predicts the transmission trajectories of the Italian epidemic during both periods before and after the second outbreak. By analyzing the impact of anti-epidemic measures on the spread of the disease, our findings emphasize the significance of implementing anti-epidemic preventive measures in COVID-19 modeling.
    MeSH term(s) Humans ; COVID-19/epidemiology ; Disease Outbreaks ; Epidemics ; Virus Diseases ; Italy/epidemiology
    Language English
    Publishing date 2023-08-24
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2711781-9
    ISSN 2296-2565 ; 2296-2565
    ISSN (online) 2296-2565
    ISSN 2296-2565
    DOI 10.3389/fpubh.2023.1223039
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: SEIR models in the light of Critical Realism - A critique of exaggerated claims about the effectiveness of Covid 19 vaccinations.

    Klement, Rainer J / Walach, Harald

    Futures

    2023  Volume 148, Page(s) 103119

    Abstract: In a recent modeling study Watson et al. (Lancet Infect Dis 2022;3099:1-10) claim that Covid-19 ... on an epidemiological susceptible-exposed-infectious-recovered (SEIR) model trained on partially simulated data and ... several caveats of this model and caution against believing in its predictions. We argue that the absence ...

    Abstract In a recent modeling study Watson et al. (Lancet Infect Dis 2022;3099:1-10) claim that Covid-19 vaccinations have helped to prevent roughly 14-20 million deaths in 2021. This conclusion is based on an epidemiological susceptible-exposed-infectious-recovered (SEIR) model trained on partially simulated data and yielding a reproduction number distribution which was then applied to a counterfactual scenario in which the efficacy of vaccinations was removed. Drawing on the meta-theory of Critical Realism, we point out several caveats of this model and caution against believing in its predictions. We argue that the absence of vaccinations would have significantly changed the causal tendencies of the system being modelled, yielding a different reproduction number than obtained from training the model on actually observed data. Furthermore, the model omits many important causal factors. Therefore this model, similar to many previous SEIR models, has oversimplified the complex interplay between biomedical, social and cultural dimensions of health and should not be used to guide public health policy. In order to predict the future in epidemic situations more accurately, continuously optimized dynamic causal models which can include the not directly tangible, yet real causal mechanisms affecting public health appear to be a promising alternative to SEIR-type models.
    Language English
    Publishing date 2023-02-12
    Publishing country England
    Document type Journal Article
    ZDB-ID 2013109-4
    ISSN 0016-3287
    ISSN 0016-3287
    DOI 10.1016/j.futures.2023.103119
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Book ; Online: Mathematical and Computer Modeling of COVID-19 Transmission Dynamics in Bulgaria by Time-depended Inverse SEIR Model

    Margenov, Svetozar / Popivanov, Nedyu / Ugrinova, Iva / Harizanov, Stanislav / Hristov, Tsvetan

    2020  

    Abstract: ... In fact, based on these results we model the COVID-19 transmission dynamics in Bulgaria and make a two ... In this paper we explore a time-depended SEIR model, in which the dynamics of the infection in four ... for the development of the epidemic. This is the reason for using Bulgarian COVID-19 data to first of all, solve ...

    Abstract In this paper we explore a time-depended SEIR model, in which the dynamics of the infection in four groups from a selected target group (population), divided according to the infection, are modeled by a system of nonlinear ordinary differential equations. Several basic parameters are involved in the model: coefficients of infection rate, incubation rate, recovery rate. The coefficients are adaptable to each specific infection, for each individual country, and depend on the measures to limit the spread of the infection and the effectiveness of the methods of treatment of the infected people in the respective country. If such coefficients are known, solving the nonlinear system is possible to be able to make some hypotheses for the development of the epidemic. This is the reason for using Bulgarian COVID-19 data to first of all, solve the so-called "inverse problem" and to find the parameters of the current situation. Reverse logic is initially used to determine the parameters of the model as a function of time, followed by computer solution of the problem. Namely, this means predicting the future behavior of these parameters, and finding (and as a consequence applying mass-scale measures, e.g., distancing, disinfection, limitation of public events), a suitable scenario for the change in the proportion of the numbers of the four studied groups in the future. In fact, based on these results we model the COVID-19 transmission dynamics in Bulgaria and make a two-week forecast for the numbers of new cases per day, active cases and recovered individuals. Such model, as we show, has been successful for prediction analysis in the Bulgarian situation. We also provide multiple examples of numerical experiments with visualization of the results.

    Comment: keywords: Nonlinear approximation, Mathematical modeling, data extrapolation
    Keywords Quantitative Biology - Populations and Evolution ; Physics - Physics and Society
    Subject code 612
    Publishing date 2020-08-20
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article: Mathematical and Computer Modeling of COVID-19 Transmission Dynamics in Bulgaria by Time-depended Inverse SEIR Model

    Margenov, Svetozar / Popivanov, Nedyu / Ugrinova, Iva / Harizanov, Stanislav / Hristov, Tsvetan

    Abstract: ... In fact, based on these results we model the COVID-19 transmission dynamics in Bulgaria and make a two ... In this paper we explore a time-depended SEIR model, in which the dynamics of the infection in four ... for the development of the epidemic. This is the reason for using Bulgarian COVID-19 data to first of all, solve ...

    Abstract In this paper we explore a time-depended SEIR model, in which the dynamics of the infection in four groups from a selected target group (population), divided according to the infection, are modeled by a system of nonlinear ordinary differential equations. Several basic parameters are involved in the model: coefficients of infection rate, incubation rate, recovery rate. The coefficients are adaptable to each specific infection, for each individual country, and depend on the measures to limit the spread of the infection and the effectiveness of the methods of treatment of the infected people in the respective country. If such coefficients are known, solving the nonlinear system is possible to be able to make some hypotheses for the development of the epidemic. This is the reason for using Bulgarian COVID-19 data to first of all, solve the so-called"inverse problem"and to find the parameters of the current situation. Reverse logic is initially used to determine the parameters of the model as a function of time, followed by computer solution of the problem. Namely, this means predicting the future behavior of these parameters, and finding (and as a consequence applying mass-scale measures, e.g., distancing, disinfection, limitation of public events), a suitable scenario for the change in the proportion of the numbers of the four studied groups in the future. In fact, based on these results we model the COVID-19 transmission dynamics in Bulgaria and make a two-week forecast for the numbers of new cases per day, active cases and recovered individuals. Such model, as we show, has been successful for prediction analysis in the Bulgarian situation. We also provide multiple examples of numerical experiments with visualization of the results.
    Keywords covid19
    Publisher ArXiv
    Document type Article
    Database COVID19

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