The transmission dynamics of a pertussis-pneumonia co-infection model is analyzed. takes into account temporary immunity infected infants and includes maternally derived compartment. basic reproduction number the co-infected obtained using next generation matrix, stability analysis carried out. exhibits four equilibria, namely, pertussis-free equilibrium, pneumonia-free co-infection-free equili...

We present and analyze a nonlinear dynamical system modelling forest-pests interactions and the way they are affected by acidic deposition. The model includes mechanisms of carbon and nitrogen exchange between soil and vegetation, biomass decomposition and microbial mineralization, and defoliation by pest grazers, which are partially controlled by avian or mammalian predators. Acidic deposition...

A disease transmission model of SEIRS type with distributed delays in latent and temporary immune periods is discussed. With general/particular probability distributions in both of these periods, we address the threshold property of the basic reproduction number R0 and the dynamical properties of the disease-free/endemic equilibrium points present in the model. More specifically, we 1. show the...

In this paper, with the assumptions that an infectious disease in a population has a fixed latent period and the latent individuals of the population may disperse, we formulate an SIR model with a simple demographic structure for the population living in an n-patch environment (cities, towns, or countries, etc.). The model is given by a system of delay differential equations with a fixed delay ...

In this paper we the study of dynamics time since infection structured vector born model with direct transmission. We use standard incidence term to new infections. analyze corresponding system partial differential equation and obtain an explicit formula for basic reproduction number ℜ 0 . The diseases-free equilibrium is locally globally asymptotically stable whenever less than one, < 1. En...

We analyze stability of equilibria for a delayed SIR epidemic model, in which population growth is subject to logistic growth in absence of disease, with a nonlinear incidence rate satisfying suitable monotonicity conditions. The model admits a unique endemic equilibrium if and only if the basic reproduction number R0 exceeds one, while the trivial equilibrium and the disease-free equilibrium a...

We analyze mathematical models for COVID-19 with discrete time delays and vaccination. Sufficient conditions the local stability of endemic disease-free equilibrium points are proved any positive delay. The results illustrated through numerical simulations performed in MATLAB.