One of the deadliest viral diseases in the world is Ebola virus disease. There are different types of Ebola virus with the Zaire Ebola Virus in DR Congo being very virulent resulting with a high disease induced rate. The resurgence of this disease makes it a necessity for a more robust modelling approach to understand its dynamics for proper policy implementation. In this work, a novel nonlinear mathematical model is developed using compartmental approach which is common in epidemiological modelling. The developed model strategically incorporated quarantine through contact tracing and mandatory vaccination of all quarantined individuals who are tested to be negative after the incubation period. In addition to this intervention strategy, a number of susceptible and recovered individuals with a waned immunity are also vaccinated. The developed model was assessed to be biologically feasible. The next generation matrix was used to determine the basic reproduction number while the Jacobian approach was used to linearise the system leading it into its stability analysis. Additionally, the 4th Order Runge Kutta iterative scheme was extended on the model for simulations purposes. The results show that the model has two fixed points. These are the disease-free equilibrium point where the disease will fail to exist within the population, and the endemic point at which the disease will continue to persist within the population. The model was examined to be stable with all eigenvalues being negative. The numerical results showed that the appearance of the disease in the population will cause a rise in the number of exposed, quarantined, and infected compartments. This will lead to a decline in the number of susceptible persons. The basic reproduction number was attained to be 0.09779 indicating that the Zaire Ebola Virus disease will fail to exist over time. It is therefore realised that the developed model with the incorporated interventions is an effective approach to control Zaire Ebola Virus if the strategies are efficiently implemented.
| Published in | American Journal of Health Research (Volume 13, Issue 5) |
| DOI | 10.11648/j.ajhr.20251305.14 |
| Page(s) | 281-293 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2025. Published by Science Publishing Group |
Vaccination, Quarantine, Runge Kutta, Basic Reproduction Number, Disease-Free Equilibrium
(1) Parameters | Description |
|---|---|
| Fraction of the susceptible individuals who are exposed |
| Natural birth rate |
| Progression rate of exposed individuals who are identified, contact traced and quarantined |
| Proportion of quarantined individuals who are tested to be infected |
| Recovery rate of infected individuals |
| Rate of recovered individuals who lose immunity into the susceptible compartment |
| Rate at which exposed non-contact traced persons revert into susceptible compartment |
| Natural death rate. |
| Rate at which non-contact traced exposed individuals move into infected compartment. |
| Both disease induced and natural death rate |
| Rate at which susceptible individuals receive vaccination. |
| Rate at which vaccinated individuals lose immunity to become susceptible. |
| Fraction of recovered whose immunity wanes over time get vaccinated |
| Proportion of the quarantined individuals who are tested to be negative and vaccinated. |
(2)
.
as:
(3)
and its endemic equilibrium
. At the
, we set
and solve for
and
. This yields:
(4)
, the Zaire Ebola Virus disease persist in the population over time. The endemic equilibriums deduced from Equation (2) yields:
(5)
is the average number of secondary infections caused by a single infected individual in a fully susceptible population. In this Zaire Ebola Virus disease model in Equation (2),
is derived from the exposed and infected compartments as:
(6)
of the model. Here, we let
. The NGM is such that Equation (6) is decomposed into two matrices. This gives
(7)
is the transmission matrix and
is the transition matrix.
(8)
(9)
(10)
, the Zaire Ebola Virus disease will die out, else the disease will continue to persist since the number of infectious cases will continue to rise. This will cause the system to be unstable.
at the
. We further compute the eigenvalues of
to enable us use the sign of the eigenvalues to evaluate the stability of the disease.
of this model is less than one, else unstable.
is given by:
(11)
and
It is seen than
Also, the sixth eigenvalue is
yields
(12)
all the eigenvalues of
are negatives. Therefore,
is LAS. At this LAS point, there will be no EBOV disease threat in the population. Additionally, if
thus
. Hence,
becomes unstable anytime
and
(13)
(14)
(15)
(16)
(17)
(18) Compartment | Value/millions | Source |
|---|---|---|
18.8 | [ 28, 4] | |
0.25 | [ 28, 4] | |
0.0001 | [ 28, 29] | |
0.003481 | [ 28, 29] | |
0.001162 | [ 28, 29] | |
0.303 | [ 28, 29] | |
Parameter | ||
0.28770 | [ 17, 24, 4] | |
0.02020 | Assumed | |
0.09410 | Assumed | |
0.09000 | Assumed | |
0.33380 | Computed | |
0.02000 | Assumed | |
0.09500 | Assumed | |
0.00500 | Assumed | |
0.76130 | [ 17, 24, 4] | |
0.53000 | [ 30, 31] | |
0.08000 | Assumed | |
0.00200 | Assumed | |
0.07000 | Assumed | |
0.02000 | Assumed | |
. Also, the vaccination strategy was applied in three compartments as seen in Figure 1. We considered a variation in
respectively as all other values remain unchanged over time.
increases, the number of quarantiened individuals increase in Figure 3(c). The impact of this is that, the number of susceptibility declines in Figure 3(a). Also, the immediate peak of the exposed compartments in Figure 3(b) declines, while the infected compartment in Figure 3(d) which experienced an earlier rise in the number of cases also declined to zero in less than two months. Additionally, the recovered persons shot up in the early stages of the disease, but declined as the numbers in the infected conpartment declined. Finally, the number of people vaccinated peaked but gradually decreased over time. It is seen from Figure 3 that a variation in
actually causes a change in each state or compartments. Implicitely, a proper implementation of the quarantine intervention through contact tracing has a positive effect in controlling the spread of the Ebola disease in DR congo.
causes a rapid decline in the number of susceptible persons, and a sharp peak in the exposed persons. However, the number of exposed persons reduces to near zero within the first month and finally extinguishes in less than two months (60 days). Figure 4(c) to Figure 4(e) show that an increase in
causes a change in decline in the number of persons who are quarantined, infected and recovered. This means that a change in
has its proportional change in the quarantined, infected and the recovered compartments. Additionally, Figure 4(f) shows that an increase in
increases the number of persons who are vaccinated over time. Generally, the intervention strategy to increase the rate of
has a positive ripple effect in extinguishing the disease within the shortest possible time whiles increasing the number of vaccinated persons, and further reducing the number of individuals in the susceptible chamber.
during the outbreak of Zaire Ebola disease in DR Congo.
causes a sharp decline in the susceptible compartment to near zero in less than a month, but finally goes to zero as
increases. Again, Figure 5(b) to Figure 5(e) show that, a variation in
causes a sharp rise in the number of individuals who are exposed, quarantined, infected and recovered in the first 50 days, but decline to zero by the 100th day. Additionally, an increase in
causes a proportional change in the number of exposed, quarantined, infected and recovered persons. Also, a variation in
causes a proportional variation in the number of vaccinated persons. It is further seen in Figure 5(f) that an increase in
increase the number of vaccinated individuals. Finally, the strategy to increase
has a positive impact by leaving no person to be susceptible within the population as a result of the vaccination of the total populace as seen in Figure 5(a) and Figure 5(f).
causes an immediate reduction in the number of susceptible persons. Again, 6(a) to 6(f) show that a change in
causes a proportional change in the exposed, quarantined, infected, recovered and the vaccinated compartments. Additionally, a decrease in the value of
causes a variation in the number of individuals in the exposed, quarantined, infected, recovered and vaccinated chambers. As
increases, Figure 6(b) to Figure 6(e) rise and fall to zero in less than 100 days. It is finally seen in Figure 6(f) that an increase in
increases the number of persons vaccinated over time. DR | Democratic Republic |
EVD | Ebola Virus Disease |
NGM | Next Generation Matrix |
RK4 | Runge-Kutta Order 4 |
rVsV - ZEBOV | recombinant Vesicular stomatitis Virus-Zaire Ebola Virus |
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APA Style
Nti, A. E., Ampofi, I., Baidoo, J. (2025). Modelling the Spread of Zaire Ebola Virus Disease with Quarantine and Vaccination Interventions. American Journal of Health Research, 13(5), 281-293. https://doi.org/10.11648/j.ajhr.20251305.14
ACS Style
Nti, A. E.; Ampofi, I.; Baidoo, J. Modelling the Spread of Zaire Ebola Virus Disease with Quarantine and Vaccination Interventions. Am. J. Health Res. 2025, 13(5), 281-293. doi: 10.11648/j.ajhr.20251305.14
AMA Style
Nti AE, Ampofi I, Baidoo J. Modelling the Spread of Zaire Ebola Virus Disease with Quarantine and Vaccination Interventions. Am J Health Res. 2025;13(5):281-293. doi: 10.11648/j.ajhr.20251305.14
@article{10.11648/j.ajhr.20251305.14,
author = {Alex Emmanuel Nti and Isaac Ampofi and Jehovah Baidoo},
title = {Modelling the Spread of Zaire Ebola Virus Disease with Quarantine and Vaccination Interventions
},
journal = {American Journal of Health Research},
volume = {13},
number = {5},
pages = {281-293},
doi = {10.11648/j.ajhr.20251305.14},
url = {https://doi.org/10.11648/j.ajhr.20251305.14},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajhr.20251305.14},
abstract = {One of the deadliest viral diseases in the world is Ebola virus disease. There are different types of Ebola virus with the Zaire Ebola Virus in DR Congo being very virulent resulting with a high disease induced rate. The resurgence of this disease makes it a necessity for a more robust modelling approach to understand its dynamics for proper policy implementation. In this work, a novel nonlinear mathematical model is developed using compartmental approach which is common in epidemiological modelling. The developed model strategically incorporated quarantine through contact tracing and mandatory vaccination of all quarantined individuals who are tested to be negative after the incubation period. In addition to this intervention strategy, a number of susceptible and recovered individuals with a waned immunity are also vaccinated. The developed model was assessed to be biologically feasible. The next generation matrix was used to determine the basic reproduction number while the Jacobian approach was used to linearise the system leading it into its stability analysis. Additionally, the 4th Order Runge Kutta iterative scheme was extended on the model for simulations purposes. The results show that the model has two fixed points. These are the disease-free equilibrium point where the disease will fail to exist within the population, and the endemic point at which the disease will continue to persist within the population. The model was examined to be stable with all eigenvalues being negative. The numerical results showed that the appearance of the disease in the population will cause a rise in the number of exposed, quarantined, and infected compartments. This will lead to a decline in the number of susceptible persons. The basic reproduction number was attained to be 0.09779 indicating that the Zaire Ebola Virus disease will fail to exist over time. It is therefore realised that the developed model with the incorporated interventions is an effective approach to control Zaire Ebola Virus if the strategies are efficiently implemented.
},
year = {2025}
}
TY - JOUR T1 - Modelling the Spread of Zaire Ebola Virus Disease with Quarantine and Vaccination Interventions AU - Alex Emmanuel Nti AU - Isaac Ampofi AU - Jehovah Baidoo Y1 - 2025/10/30 PY - 2025 N1 - https://doi.org/10.11648/j.ajhr.20251305.14 DO - 10.11648/j.ajhr.20251305.14 T2 - American Journal of Health Research JF - American Journal of Health Research JO - American Journal of Health Research SP - 281 EP - 293 PB - Science Publishing Group SN - 2330-8796 UR - https://doi.org/10.11648/j.ajhr.20251305.14 AB - One of the deadliest viral diseases in the world is Ebola virus disease. There are different types of Ebola virus with the Zaire Ebola Virus in DR Congo being very virulent resulting with a high disease induced rate. The resurgence of this disease makes it a necessity for a more robust modelling approach to understand its dynamics for proper policy implementation. In this work, a novel nonlinear mathematical model is developed using compartmental approach which is common in epidemiological modelling. The developed model strategically incorporated quarantine through contact tracing and mandatory vaccination of all quarantined individuals who are tested to be negative after the incubation period. In addition to this intervention strategy, a number of susceptible and recovered individuals with a waned immunity are also vaccinated. The developed model was assessed to be biologically feasible. The next generation matrix was used to determine the basic reproduction number while the Jacobian approach was used to linearise the system leading it into its stability analysis. Additionally, the 4th Order Runge Kutta iterative scheme was extended on the model for simulations purposes. The results show that the model has two fixed points. These are the disease-free equilibrium point where the disease will fail to exist within the population, and the endemic point at which the disease will continue to persist within the population. The model was examined to be stable with all eigenvalues being negative. The numerical results showed that the appearance of the disease in the population will cause a rise in the number of exposed, quarantined, and infected compartments. This will lead to a decline in the number of susceptible persons. The basic reproduction number was attained to be 0.09779 indicating that the Zaire Ebola Virus disease will fail to exist over time. It is therefore realised that the developed model with the incorporated interventions is an effective approach to control Zaire Ebola Virus if the strategies are efficiently implemented. VL - 13 IS - 5 ER -