7 research outputs found
A multi-group SEIRA model for the spread of COVID-19 among heterogeneous populations
The outbreak and propagation of COVID-19 have posed a considerable challenge
to modern society. In particular, the different restrictive actions taken by
governments to prevent the spread of the virus have changed the way humans
interact and conceive interaction. Due to geographical, behavioral, or economic
factors, different sub-groups among a population are more (or less) likely to
interact, and thus to spread/acquire the virus. In this work, we present a
general multi-group SEIRA model for representing the spread of COVID-19 among a
heterogeneous population and test it in a numerical case of study. By
highlighting its applicability and the ease with which its general formulation
can be adapted to particular studies, we expect our model to lead us to a
better understanding of the evolution of this pandemic and to better
public-health policies to control it
A multi-group SEIRA model for the spread of COVID-19 among heterogeneous populations
The outbreak and propagation of COVID-19 have posed a considerable challenge to modern society. In particular, the different restrictive actions taken by governments to prevent the spread of the virus have changed the way humans interact and conceive interaction. Due to geographical, behavioral, or economic factors, different sub-groups among a population are more (or less) likely to interact, and thus to spread/acquire the virus. In this work, we present a general multi-group SEIRA model for representing the spread of COVID-19 among a heterogeneous population and test it in a numerical case of study. By highlighting its applicability and the ease with which its general formulation can be adapted to particular studies, we expect our model to lead us to a better understanding of the evolution of this pandemic and to better public-health policies to control it
Global exponential stability for coupled systems of neutral delay differential equations
In this paper, a novel class of neutral delay differential equations (NDDEs) is presented. By using the Razumikhin method and Kirchhoff's matrix tree theorem in graph theory, the global exponential stability for such NDDEs is investigated. By constructing an appropriate Lyapunov function, two different kinds of sufficient criteria which ensure the global exponential stability of NDDEs are derived in the form of Lyapunov functions and coefficients of NDDEs, respectively. A numerical example is provided to demonstrate the effectiveness of the theoretical results
On the dynamics of a class of multi-group models for vector-borne diseases
The resurgence of vector-borne diseases is an increasing public health
concern, and there is a need for a better understanding of their dynamics. For
a number of diseases, e.g. dengue and chikungunya, this resurgence occurs
mostly in urban environments, which are naturally very heterogeneous,
particularly due to population circulation. In this scenario, there is an
increasing interest in both multi-patch and multi-group models for such
diseases. In this work, we study the dynamics of a vector borne disease within
a class of multi-group models that extends the classical Bailey-Dietz model.
This class includes many of the proposed models in the literature, and it can
accommodate various functional forms of the infection force. For such models,
the vector-host/host-vector contact network topology gives rise to a bipartite
graph which has different properties from the ones usually found in directly
transmitted diseases. Under the assumption that the contact network is strongly
connected, we can define the basic reproductive number and show
that this system has only two equilibria: the so called disease free
equilibrium (DFE); and a unique interior equilibrium---usually termed the
endemic equilibrium (EE)---that exists if, and only if, . We
also show that, if , then the DFE equilibrium is globally
asymptotically stable, while when , we have that the EE is
globally asymptotically stable
Global Dynamics for a Novel Differential Infectivity Epidemic Model with Stage Structure
A novel differential infectivity epidemic model with stage structure is formulated and studied. Under biological motivation, the stability of equilibria is investigated by the global Lyapunov functions. Some novel techniques are applied to the global dynamics analysis for the differential infectivity epidemic model. Uniform persistence and the sharp threshold dynamics are established; that is, the reproduction number determines the global dynamics of the system. Finally, numerical simulations are given to illustrate the main theoretical results