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  1. Article ; Online: Bayesian inference for dynamical systems.

    Roda, Weston C

    Infectious Disease Modelling

    2020  Volume 5, Page(s) 221–232

    Abstract: Bayesian inference is a common method for conducting parameter estimation for dynamical systems. Despite the prevalent use of Bayesian inference for performing parameter estimation for dynamical systems, there is a need for a formalized and detailed ... ...

    Abstract Bayesian inference is a common method for conducting parameter estimation for dynamical systems. Despite the prevalent use of Bayesian inference for performing parameter estimation for dynamical systems, there is a need for a formalized and detailed methodology. This paper presents a comprehensive methodology for dynamical system parameter estimation using Bayesian inference and it covers utilizing different distributions, Markov Chain Monte Carlo (MCMC) sampling, obtaining credible intervals for parameters, and prediction intervals for solutions. A logistic growth example is given to illustrate the methodology.
    Language English
    Publishing date 2020-01-10
    Publishing country China
    Document type Journal Article
    ZDB-ID 3015225-2
    ISSN 2468-0427 ; 2468-2152
    ISSN (online) 2468-0427
    ISSN 2468-2152
    DOI 10.1016/j.idm.2019.12.007
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Modeling the Effects of Latency Reversing Drugs During HIV-1 and SIV Brain Infection with Implications for the "Shock and Kill" Strategy.

    Roda, Weston C / Liu, Suli / Power, Christopher / Li, Michael Y

    Bulletin of mathematical biology

    2021  Volume 83, Issue 4, Page(s) 39

    Abstract: Combination antiretroviral therapy (cART) has greatly increased life expectancy for human immunodeficiency virus-1 (HIV-1)-infected patients. Even given the remarkable success of cART, the virus persists in many different cells and tissues. The presence ... ...

    Abstract Combination antiretroviral therapy (cART) has greatly increased life expectancy for human immunodeficiency virus-1 (HIV-1)-infected patients. Even given the remarkable success of cART, the virus persists in many different cells and tissues. The presence of viral reservoirs represents a major obstacle to HIV-1 eradication. These viral reservoirs contain latently infected long-lived cells. The "Shock and Kill" therapeutic strategy aims to reactivate latently infected cells by latency reversing agents (LRAs) and kill these reactivated cells by strategies involving the host immune system. The brain is a natural anatomical reservoir for HIV-1 infection. Brain macrophages, including microglia and perivascular macrophages, display productive HIV-1 infection. A mathematical model was used to analyze the dynamics of latently and productively infected brain macrophages during viral infection and this mathematical model enabled prediction of the effects of LRAs applied to the "Shock and Kill" strategy in the brain. The model was calibrated using reported data from simian immunodeficiency virus (SIV) studies. Our model produces the overarching observation that effective cART can suppress productively infected brain macrophages but leaves a residual latent viral reservoir in brain macrophages. In addition, our model demonstrates that there exists a parameter regime wherein the "Shock and Kill" strategy can be safe and effective for SIV infection in the brain. The results indicate that the "Shock and Kill" strategy can restrict brain viral RNA burden associated with severe neuroinflammation and can lead to the eradication of the latent reservoir of brain macrophages.
    MeSH term(s) Animals ; Antiviral Agents/therapeutic use ; Brain/virology ; HIV Infections/drug therapy ; HIV Infections/prevention & control ; HIV-1 ; Humans ; Models, Biological ; Simian Acquired Immunodeficiency Syndrome/drug therapy ; Simian Acquired Immunodeficiency Syndrome/prevention & control ; Simian Immunodeficiency Virus
    Chemical Substances Antiviral Agents
    Language English
    Publishing date 2021-03-12
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 184905-0
    ISSN 1522-9602 ; 0007-4985 ; 0092-8240
    ISSN (online) 1522-9602
    ISSN 0007-4985 ; 0092-8240
    DOI 10.1007/s11538-021-00875-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Mathematical modeling of the dynamics of COVID-19 variants of concern: Asymptotic and finite-time perspectives.

    Ciupeanu, Adriana-Stefania / Varughese, Marie / Roda, Weston C / Han, Donglin / Cheng, Qun / Li, Michael Y

    Infectious Disease Modelling

    2022  Volume 7, Issue 4, Page(s) 581–596

    Abstract: The COVID-19 pandemic has seen multiple waves, in part due to the implementation and relaxation of social distancing measures by the public health authorities around the world, and also caused by the emergence of new variants of concern (VOCs) of the ... ...

    Abstract The COVID-19 pandemic has seen multiple waves, in part due to the implementation and relaxation of social distancing measures by the public health authorities around the world, and also caused by the emergence of new variants of concern (VOCs) of the SARS-Cov-2 virus. As the COVID-19 pandemic is expected to transition into an endemic state, how to manage outbreaks caused by newly emerging VOCs has become one of the primary public health issues. Using mathematical modeling tools, we investigated the dynamics of VOCs, both in a general theoretical framework and based on observations from public health data of past COVID-19 waves, with the objective of understanding key factors that determine the dominance and coexistence of VOCs. Our results show that the transmissibility advantage of a new VOC is a main factor for it to become dominant. Additionally, our modeling study indicates that the initial number of people infected with the new VOC plays an important role in determining the size of the epidemic. Our results also support the evidence that public health measures targeting the newly emerging VOC taken in the early phase of its spread can limit the size of the epidemic caused by the new VOC (Wu et al., 2139Wu, Scarabel, Majeed, Bragazzi, & Orbinski,

    Wu et al., 2021).
    Language English
    Publishing date 2022-09-08
    Publishing country China
    Document type Journal Article
    ZDB-ID 3015225-2
    ISSN 2468-0427 ; 2468-2152
    ISSN (online) 2468-0427
    ISSN 2468-2152
    DOI 10.1016/j.idm.2022.08.004
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Why is it difficult to accurately predict the COVID-19 epidemic?

    Roda, Weston C / Varughese, Marie B / Han, Donglin / Li, Michael Y

    Infectious Disease Modelling

    2020  Volume 5, Page(s) 271–281

    Abstract: Since the COVID-19 outbreak in Wuhan City in December of 2019, numerous model predictions on the COVID-19 epidemics in Wuhan and other parts of China have been reported. These model predictions have shown a wide range of variations. In our study, we ... ...

    Abstract Since the COVID-19 outbreak in Wuhan City in December of 2019, numerous model predictions on the COVID-19 epidemics in Wuhan and other parts of China have been reported. These model predictions have shown a wide range of variations. In our study, we demonstrate that nonidentifiability in model calibrations using the confirmed-case data is the main reason for such wide variations. Using the Akaike Information Criterion (AIC) for model selection, we show that an SIR model performs much better than an SEIR model in representing the information contained in the confirmed-case data. This indicates that predictions using more complex models may not be more reliable compared to using a simpler model. We present our model predictions for the COVID-19 epidemic in Wuhan after the lockdown and quarantine of the city on January 23, 2020. We also report our results of modeling the impacts of the strict quarantine measures undertaken in the city after February 7 on the time course of the epidemic, and modeling the potential of a second outbreak after the return-to-work in the city.
    Keywords covid19
    Language English
    Publishing date 2020-03-25
    Publishing country China
    Document type Journal Article
    ZDB-ID 3015225-2
    ISSN 2468-0427 ; 2468-2152
    ISSN (online) 2468-0427
    ISSN 2468-2152
    DOI 10.1016/j.idm.2020.03.001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Why is it difficult to accurately predict the COVID-19 epidemic?

    Roda, Weston C. / Varughese, Marie B. / Han, Donglin / Li, Michael Y.

    Infectious Disease Modelling

    2020  Volume 5, Page(s) 271–281

    Keywords covid19
    Language English
    Publisher Elsevier BV
    Publishing country us
    Document type Article ; Online
    ZDB-ID 3015225-2
    ISSN 2468-0427 ; 2468-2152
    ISSN (online) 2468-0427
    ISSN 2468-2152
    DOI 10.1016/j.idm.2020.03.001
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Why is it difficult to accurately predict the COVID-19 epidemic?

    Weston C. Roda / Marie B. Varughese / Donglin Han / Michael Y. Li

    Infectious Disease Modelling, Vol 5, Iss , Pp 271-

    2020  Volume 281

    Abstract: Since the COVID-19 outbreak in Wuhan City in December of 2019, numerous model predictions on the COVID-19 epidemics in Wuhan and other parts of China have been reported. These model predictions have shown a wide range of variations. In our study, we ... ...

    Abstract Since the COVID-19 outbreak in Wuhan City in December of 2019, numerous model predictions on the COVID-19 epidemics in Wuhan and other parts of China have been reported. These model predictions have shown a wide range of variations. In our study, we demonstrate that nonidentifiability in model calibrations using the confirmed-case data is the main reason for such wide variations. Using the Akaike Information Criterion (AIC) for model selection, we show that an SIR model performs much better than an SEIR model in representing the information contained in the confirmed-case data. This indicates that predictions using more complex models may not be more reliable compared to using a simpler model. We present our model predictions for the COVID-19 epidemic in Wuhan after the lockdown and quarantine of the city on January 23, 2020. We also report our results of modeling the impacts of the strict quarantine measures undertaken in the city after February 7 on the time course of the epidemic, and modeling the potential of a second outbreak after the return-to-work in the city. Keywords: COVID-19 epidemic in Wuhan, SIR and SEIR models, Bayesian inference, Model selection, Nonidentifiability, Quarantine, Peak time of epidemic
    Keywords Infectious and parasitic diseases ; RC109-216 ; covid19
    Subject code 612
    Language English
    Publishing date 2020-01-01T00:00:00Z
    Publisher KeAi
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article: Why is it difficult to accurately predict the COVID-19 epidemic?

    Roda, Weston C. / Varughese, Marie B. / Han, Donglin / Li, Michael Y.

    Infect. Dis. Modelling

    Abstract: Since the COVID-19 outbreak in Wuhan City in December of 2019, numerous model predictions on the COVID-19 epidemics in Wuhan and other parts of China have been reported. These model predictions have shown a wide range of variations. In our study, we ... ...

    Abstract Since the COVID-19 outbreak in Wuhan City in December of 2019, numerous model predictions on the COVID-19 epidemics in Wuhan and other parts of China have been reported. These model predictions have shown a wide range of variations. In our study, we demonstrate that nonidentifiability in model calibrations using the confirmed-case data is the main reason for such wide variations. Using the Akaike Information Criterion (AIC) for model selection, we show that an SIR model performs much better than an SEIR model in representing the information contained in the confirmed-case data. This indicates that predictions using more complex models may not be more reliable compared to using a simpler model. We present our model predictions for the COVID-19 epidemic in Wuhan after the lockdown and quarantine of the city on January 23, 2020. We also report our results of modeling the impacts of the strict quarantine measures undertaken in the city after February 7 on the time course of the epidemic, and modeling the potential of a second outbreak after the return-to-work in the city.
    Keywords covid19
    Publisher WHO
    Document type Article
    Note WHO #Covidence: #15074
    Database COVID19

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  8. Article ; Online: Why is it difficult to accurately predict the COVID-19 epidemic?

    Roda, Weston C. / Varughese, Marie B. / Han, Donglin / Li, Michael

    Infectious disease modelling, 5:271-281

    2020  

    Abstract: Since the COVID-19 outbreak in Wuhan City in December of 2019, numerous model predictions on the COVID-19 epidemics in Wuhan and other parts of China have been reported. These model predictions have shown a wide range of variations. In our study, we ... ...

    Abstract Since the COVID-19 outbreak in Wuhan City in December of 2019, numerous model predictions on the COVID-19 epidemics in Wuhan and other parts of China have been reported. These model predictions have shown a wide range of variations. In our study, we demonstrate that nonidentifiability in model calibrations using the confirmed-case data is the main reason for such wide variations. Using the Akaike Information Criterion (AIC) for model selection, we show that an SIR model performs much better than an SEIR model in representing the information contained in the confirmed-case data. This indicates that predictions using more complex models may not be more reliable compared to using a simpler model. We present our model predictions for the COVID-19 epidemic in Wuhan after the lockdown and quarantine of the city on January 23, 2020. We also report our results of modeling the impacts of the strict quarantine measures undertaken in the city after February 7 on the time course of the epidemic, and modeling the potential of a second outbreak after the return-to-work in the city.
    Keywords Quarantine ; COVID-19 ; Wuhan ; Model selection ; Nonidentifiability ; SIR and SEIR models ; Bayesian inference ; Peak time of epidemic ; epidemic ; covid19
    Language English
    Publishing country de
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Effectiveness of maternal influenza vaccination during pregnancy against laboratory-confirmed seasonal influenza among infants under 6 months of age in Ontario, Canada.

    Fell, Deshayne B / Russell, Margaret / Fung, Stephen G / Swayze, Sarah / Chung, Hannah / Buchan, Sarah A / Roda, Weston / Smolarchuk, Christa / Wilson, Kumanan / Crowcroft, Natasha / Schwartz, Kevin L / Gubbay, Jonathan B / McGeer, Allison / Smieja, Marek / Richardson, David C / Katz, Kevin / Zahariadis, George / Campigotto, Aaron / Mubareka, Samira /
    McNally, Dayre / Karnauchow, Timothy / Zelyas, Nathan / Svenson, Lawrence W / Kwong, Jeffrey C

    The Journal of infectious diseases

    2023  

    Abstract: Background: Randomized trials conducted in low- and middle-income settings demonstrated efficacy of influenza vaccination during pregnancy against influenza infection among infants <6 months of age. However, vaccine effectiveness (VE) estimates from ... ...

    Abstract Background: Randomized trials conducted in low- and middle-income settings demonstrated efficacy of influenza vaccination during pregnancy against influenza infection among infants <6 months of age. However, vaccine effectiveness (VE) estimates from settings with different population characteristics and influenza seasonality remain limited.
    Methods: We conducted a test-negative study in Ontario, Canada. All influenza virus tests among infants <6 months from 2010-2019 were identified and linked with health databases to ascertain information on maternal-infant dyads. VE was estimated from the odds ratio for influenza vaccination during pregnancy among cases versus controls, computed using logistic regression with adjustment for potential confounders.
    Results: Among 23,806 infants tested for influenza, 1,783 (7.5%) were positive and 1,708 (7.2%) were born to mothers vaccinated against influenza during pregnancy. VE against laboratory-confirmed infant influenza infection was 64% (95% confidence interval [CI]: 50%-74%). VE was similar by trimester of vaccination (1st/2nd: 66%, 40%-80%; 3rd: 63%, 46%-74%), infant age at testing (0-<2 months: 63%, 46%-75%; 2-<6 months: 64%, 36%-79%), and gestational age at birth (≥37 weeks: 64%, 50%-75%;  < 37 weeks: 61%, 4%-86%). VE against influenza hospitalization was 67% (95%CI: 50%-78%).
    Conclusions: Influenza vaccination during pregnancy offers effective protection to infants <6 months, for whom vaccines are not currently available.
    Language English
    Publishing date 2023-11-29
    Publishing country United States
    Document type Journal Article
    ZDB-ID 3019-3
    ISSN 1537-6613 ; 0022-1899
    ISSN (online) 1537-6613
    ISSN 0022-1899
    DOI 10.1093/infdis/jiad539
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Modeling brain lentiviral infections during antiretroviral therapy in AIDS.

    Roda, Weston C / Li, Michael Y / Akinwumi, Michael S / Asahchop, Eugene L / Gelman, Benjamin B / Witwer, Kenneth W / Power, Christopher

    Journal of neurovirology

    2017  Volume 23, Issue 4, Page(s) 577–586

    Abstract: Understanding HIV-1 replication and latency in different reservoirs is an ongoing challenge in the care of patients with HIV/AIDS. A mathematical model was created to describe and predict the viral dynamics of HIV-1 and SIV infection within the brain ... ...

    Abstract Understanding HIV-1 replication and latency in different reservoirs is an ongoing challenge in the care of patients with HIV/AIDS. A mathematical model was created to describe and predict the viral dynamics of HIV-1 and SIV infection within the brain during effective combination antiretroviral therapy (cART). The mathematical model was formulated based on the biology of lentiviral infection of brain macrophages and used to describe the dynamics of transmission and progression of lentiviral infection in brain. Based on previous reports quantifying total viral DNA levels in brain from HIV-1 and SIV infections, estimates of integrated proviral DNA burden were made, which were used to calibrate the mathematical model predicting viral accrual in brain macrophages from primary infection. The annual rate at which susceptible brain macrophages become HIV-1 infected was estimated to be 2.90×10
    MeSH term(s) Animals ; Anti-HIV Agents/pharmacology ; Antiretroviral Therapy, Highly Active ; Brain/drug effects ; Brain/virology ; Disease Eradication/statistics & numerical data ; HIV Infections/drug therapy ; HIV Infections/virology ; HIV-1/drug effects ; HIV-1/growth & development ; Humans ; Macaca mulatta ; Models, Statistical ; Simian Acquired Immunodeficiency Syndrome/drug therapy ; Simian Acquired Immunodeficiency Syndrome/virology ; Simian Immunodeficiency Virus/drug effects ; Simian Immunodeficiency Virus/growth & development ; Viral Load/drug effects
    Chemical Substances Anti-HIV Agents
    Language English
    Publishing date 2017-05-16
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1283265-0
    ISSN 1538-2443 ; 1355-0284
    ISSN (online) 1538-2443
    ISSN 1355-0284
    DOI 10.1007/s13365-017-0530-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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