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Codimension-one bifurcation and stability analysis in an immunosuppressive infection model
1Department of Mathematics, University of Bojnord, Bojnord, Islamic Republic of Iran.
This study analyzes mathematical models for HIV and hepatitis, revealing how parameter changes affect disease dynamics. It identifies specific bifurcations in models with and without time delays, crucial for understanding disease spread.
Area of Science:
- Mathematical Biology
- Epidemiology
- Dynamical Systems Theory
Background:
- Infectious diseases like HIV and hepatitis pose significant global health challenges, necessitating robust mathematical models for analysis.
- Understanding the parametric behavior of these disease models is crucial for predicting and controlling outbreaks.
Purpose of the Study:
- To investigate the stability and codimension-one bifurcation points of differential equation systems for HIV and hepatitis.
- To analyze the impact of time delays on the dynamical behavior of these infectious disease models.
Main Methods:
- Analysis of differential equations systems representing HIV and hepatitis.
- Application of stability theory and codimension-one bifurcation analysis.
- Utilizing center manifold theory to analyze the delayed differential equation model.
Main Results:
- The study demonstrates that variations in model parameters alter the dynamical behavior of HIV and hepatitis models.
- In the absence of a delay parameter, the models exhibit saddle-node and transcritical bifurcations.
- The presence of a delay parameter leads to a saddle-node bifurcation in the investigated model.
Conclusions:
- Mathematical models, both with and without time delays, are essential for understanding the complex dynamics of infectious diseases like HIV and hepatitis.
- Bifurcation analysis provides critical insights into potential shifts in disease behavior as parameters change, informing public health strategies.
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