Modeling, analyzing and simulating the dynamics of Lassa fever in Nigeria

Document Type : Original Article

Author

1 Department of Mathematical Sciences, University of South Africa, Florida, South Africa.

2 Thermo Fisher Scientific, Microbiology Division, Lenexa, USA.

https://doi.org/10.1186/s42787-022-00138-x

Abstract

Lassa fever is an infectious and zoonotic disease with incidence ranging between a
hundred to three hundred thousand cases, with approximately five thousand deaths
reported yearly in West Africa. This disease has become endemic in the Lassa belt
of Sub-Saharan Africa, thus increasing the health burden in these regions including
Nigeria. A deterministic mathematical model is presented to study the dynamics of
Lassa fever in Nigeria. The model describes the transmission between two interacting
hosts, namely the human and rodent populations. Using the cumulative number
of cases reported by the Nigerian Centre for Disease Control within the first week of
January 2020 through the eleventh week in 2021, we performed the model fitting and
parameterization using the nonlinear least square method. The reproduction number
R0 which measures the potential spread of Lassa fever in the population is used to
investigate the local and global stability of the system. The result shows that the model
system is locally and globally asymptomatically stable whenever R0 < 1 , otherwise
it is unstable. Furthermore, the endemic equilibrium stability is investigated and the
criteria for the existence of the phenomenon of bifurcation is presented. We performed
the sensitivity analysis of each reproduction number parameter and solutions of the
developed model are derived through an iterative numerical technique, a six-stage
fifth-order Runge–Kutta method. Numerical simulations of the total infected human
population (Eh + Ih) under different numerical values (controlled parameters) are presented.
The result from this study shows that combined controlled parameters made
the total infected human population decline faster and thus reduces Lassa fever’s
burden on the population.Lassa fever is an infectious and zoonotic disease with incidence ranging between a
hundred to three hundred thousand cases, with approximately five thousand deaths
reported yearly in West Africa. This disease has become endemic in the Lassa belt
of Sub-Saharan Africa, thus increasing the health burden in these regions including
Nigeria. A deterministic mathematical model is presented to study the dynamics of
Lassa fever in Nigeria. The model describes the transmission between two interacting
hosts, namely the human and rodent populations. Using the cumulative number
of cases reported by the Nigerian Centre for Disease Control within the first week of
January 2020 through the eleventh week in 2021, we performed the model fitting and
parameterization using the nonlinear least square method. The reproduction number
R0 which measures the potential spread of Lassa fever in the population is used to
investigate the local and global stability of the system. The result shows that the model
system is locally and globally asymptomatically stable whenever R0 < 1 , otherwise
it is unstable. Furthermore, the endemic equilibrium stability is investigated and the
criteria for the existence of the phenomenon of bifurcation is presented. We performed
the sensitivity analysis of each reproduction number parameter and solutions of the
developed model are derived through an iterative numerical technique, a six-stage
fifth-order Runge–Kutta method. Numerical simulations of the total infected human
population (Eh + Ih) under different numerical values (controlled parameters) are presented.
The result from this study shows that combined controlled parameters made
the total infected human population decline faster and thus reduces Lassa fever’s
burden on the population.Lassa fever is an infectious and zoonotic disease with incidence ranging between a
hundred to three hundred thousand cases, with approximately five thousand deaths
reported yearly in West Africa. This disease has become endemic in the Lassa belt
of Sub-Saharan Africa, thus increasing the health burden in these regions including
Nigeria. A deterministic mathematical model is presented to study the dynamics of
Lassa fever in Nigeria. The model describes the transmission between two interacting
hosts, namely the human and rodent populations. Using the cumulative number
of cases reported by the Nigerian Centre for Disease Control within the first week of
January 2020 through the eleventh week in 2021, we performed the model fitting and
parameterization using the nonlinear least square method. The reproduction number
R0 which measures the potential spread of Lassa fever in the population is used to
investigate the local and global stability of the system. The result shows that the model
system is locally and globally asymptomatically stable whenever R0 < 1 , otherwise
it is unstable. Furthermore, the endemic equilibrium stability is investigated and the
criteria for the existence of the phenomenon of bifurcation is presented. We performed
the sensitivity analysis of each reproduction number parameter and solutions of the
developed model are derived through an iterative numerical technique, a six-stage
fifth-order Runge–Kutta method. Numerical simulations of the total infected human
population (Eh + Ih) under different numerical values (controlled parameters) are presented.
The result from this study shows that combined controlled parameters made
the total infected human population decline faster and thus reduces Lassa fever’s
burden on the population.Lassa fever is an infectious and zoonotic disease with incidence ranging between a
hundred to three hundred thousand cases, with approximately five thousand deaths
reported yearly in West Africa. This disease has become endemic in the Lassa belt
of Sub-Saharan Africa, thus increasing the health burden in these regions including
Nigeria. A deterministic mathematical model is presented to study the dynamics of
Lassa fever in Nigeria. The model describes the transmission between two interacting
hosts, namely the human and rodent populations. Using the cumulative number
of cases reported by the Nigerian Centre for Disease Control within the first week of
January 2020 through the eleventh week in 2021, we performed the model fitting and
parameterization using the nonlinear least square method. The reproduction number
R0 which measures the potential spread of Lassa fever in the population is used to
investigate the local and global stability of the system. The result shows that the model
system is locally and globally asymptomatically stable whenever R0 < 1 , otherwise
it is unstable. Furthermore, the endemic equilibrium stability is investigated and the
criteria for the existence of the phenomenon of bifurcation is presented. We performed
the sensitivity analysis of each reproduction number parameter and solutions of the
developed model are derived through an iterative numerical technique, a six-stage
fifth-order Runge–Kutta method. Numerical simulations of the total infected human
population (Eh + Ih) under different numerical values (controlled parameters) are presented.
The result from this study shows that combined controlled parameters made
the total infected human population decline faster and thus reduces Lassa fever’s
burden on the population.Lassa fever is an infectious and zoonotic disease with incidence ranging between a
hundred to three hundred thousand cases, with approximately five thousand deaths
reported yearly in West Africa. This disease has become endemic in the Lassa belt
of Sub-Saharan Africa, thus increasing the health burden in these regions including
Nigeria. A deterministic mathematical model is presented to study the dynamics of
Lassa fever in Nigeria. The model describes the transmission between two interacting
hosts, namely the human and rodent populations. Using the cumulative number
of cases reported by the Nigerian Centre for Disease Control within the first week of
January 2020 through the eleventh week in 2021, we performed the model fitting and
parameterization using the nonlinear least square method. The reproduction number
R0 which measures the potential spread of Lassa fever in the population is used to
investigate the local and global stability of the system. The result shows that the model
system is locally and globally asymptomatically stable whenever R0 < 1 , otherwise
it is unstable. Furthermore, the endemic equilibrium stability is investigated and the
criteria for the existence of the phenomenon of bifurcation is presented. We performed
the sensitivity analysis of each reproduction number parameter and solutions of the
developed model are derived through an iterative numerical technique, a six-stage
fifth-order Runge–Kutta method. Numerical simulations of the total infected human
population (Eh + Ih) under different numerical values (controlled parameters) are presented.
The result from this study shows that combined controlled parameters made
the total infected human population decline faster and thus reduces Lassa fever’s
burden on the population.Lassa fever is an infectious and zoonotic disease with incidence ranging between a
hundred to three hundred thousand cases, with approximately five thousand deaths
reported yearly in West Africa. This disease has become endemic in the Lassa belt
of Sub-Saharan Africa, thus increasing the health burden in these regions including
Nigeria. A deterministic mathematical model is presented to study the dynamics of
Lassa fever in Nigeria. The model describes the transmission between two interacting
hosts, namely the human and rodent populations. Using the cumulative number
of cases reported by the Nigerian Centre for Disease Control within the first week of
January 2020 through the eleventh week in 2021, we performed the model fitting and
parameterization using the nonlinear least square method. The reproduction number
R0 which measures the potential spread of Lassa fever in the population is used to
investigate the local and global stability of the system. The result shows that the model
system is locally and globally asymptomatically stable whenever R0 < 1 , otherwise
it is unstable. Furthermore, the endemic equilibrium stability is investigated and the
criteria for the existence of the phenomenon of bifurcation is presented. We performed
the sensitivity analysis of each reproduction number parameter and solutions of the
developed model are derived through an iterative numerical technique, a six-stage
fifth-order Runge–Kutta method. Numerical simulations of the total infected human
population (Eh + Ih) under different numerical values (controlled parameters) are presented.
The result from this study shows that combined controlled parameters made
the total infected human population decline faster and thus reduces Lassa fever’s
burden on the population.Lassa fever is an infectious and zoonotic disease with incidence ranging between a
hundred to three hundred thousand cases, with approximately five thousand deaths
reported yearly in West Africa. This disease has become endemic in the Lassa belt
of Sub-Saharan Africa, thus increasing the health burden in these regions including
Nigeria. A deterministic mathematical model is presented to study the dynamics of
Lassa fever in Nigeria. The model describes the transmission between two interacting
hosts, namely the human and rodent populations. Using the cumulative number
of cases reported by the Nigerian Centre for Disease Control within the first week of
January 2020 through the eleventh week in 2021, we performed the model fitting and
parameterization using the nonlinear least square method. The reproduction number
R0 which measures the potential spread of Lassa fever in the population is used to
investigate the local and global stability of the system. The result shows that the model
system is locally and globally asymptomatically stable whenever R0 < 1 , otherwise
it is unstable. Furthermore, the endemic equilibrium stability is investigated and the
criteria for the existence of the phenomenon of bifurcation is presented. We performed
the sensitivity analysis of each reproduction number parameter and solutions of the
developed model are derived through an iterative numerical technique, a six-stage
fifth-order Runge–Kutta method. Numerical simulations of the total infected human
population (Eh + Ih) under different numerical values (controlled parameters) are presented.
The result from this study shows that combined controlled parameters made
the total infected human population decline faster and thus reduces Lassa fever’s
burden on the population.Lassa fever is an infectious and zoonotic disease with incidence ranging between a
hundred to three hundred thousand cases, with approximately five thousand deaths
reported yearly in West Africa. This disease has become endemic in the Lassa belt
of Sub-Saharan Africa, thus increasing the health burden in these regions including
Nigeria. A deterministic mathematical model is presented to study the dynamics of
Lassa fever in Nigeria. The model describes the transmission between two interacting
hosts, namely the human and rodent populations. Using the cumulative number
of cases reported by the Nigerian Centre for Disease Control within the first week of
January 2020 through the eleventh week in 2021, we performed the model fitting and
parameterization using the nonlinear least square method. The reproduction number
R0 which measures the potential spread of Lassa fever in the population is used to
investigate the local and global stability of the system. The result shows that the model
system is locally and globally asymptomatically stable whenever R0 < 1 , otherwise
it is unstable. Furthermore, the endemic equilibrium stability is investigated and the
criteria for the existence of the phenomenon of bifurcation is presented. We performed
the sensitivity analysis of each reproduction number parameter and solutions of the
developed model are derived through an iterative numerical technique, a six-stage
fifth-order Runge–Kutta method. Numerical simulations of the total infected human
population (Eh + Ih) under different numerical values (controlled parameters) are presented.
The result from this study shows that combined controlled parameters made
the total infected human population decline faster and thus reduces Lassa fever’s
burden on the population.Lassa fever is an infectious and zoonotic disease with incidence ranging between a
hundred to three hundred thousand cases, with approximately five thousand deaths
reported yearly in West Africa. This disease has become endemic in the Lassa belt
of Sub-Saharan Africa, thus increasing the health burden in these regions including
Nigeria. A deterministic mathematical model is presented to study the dynamics of
Lassa fever in Nigeria. The model describes the transmission between two interacting
hosts, namely the human and rodent populations. Using the cumulative number
of cases reported by the Nigerian Centre for Disease Control within the first week of
January 2020 through the eleventh week in 2021, we performed the model fitting and
parameterization using the nonlinear least square method. The reproduction number
R0 which measures the potential spread of Lassa fever in the population is used to
investigate the local and global stability of the system. The result shows that the model
system is locally and globally asymptomatically stable whenever R0 < 1 , otherwise
it is unstable. Furthermore, the endemic equilibrium stability is investigated and the
criteria for the existence of the phenomenon of bifurcation is presented. We performed
the sensitivity analysis of each reproduction number parameter and solutions of the
developed model are derived through an iterative numerical technique, a six-stage
fifth-order Runge–Kutta method. Numerical simulations of the total infected human
population (Eh + Ih) under different numerical values (controlled parameters) are presented.
The result from this study shows that combined controlled parameters made
the total infected human population decline faster and thus reduces Lassa fever’s
burden on the population.

Keywords