Stochastic dynamics of an SIS epidemic model with resource constraints
To investigate the influence of environmental stochasticity on the dynamics of epidemic spread,a stochastic susceptible-infectious-susceptible(SIS)epidemiological model with resource constraints is constructed by using stochastic differential equations.Firstly,the existence and uniqueness of the global positive solutions of the stochastic epidemic model are proven by construc-ting Lyapunov function.Utilizing numerical simulation methods,the probability and duration of epidemic extinction are analyzed under various scenarios.The results show that the intensity of environmental stochasticity is positively correlated with the extinction probability of epidemic,and negatively correlated with the extinction time of epidemic.Specifically,when the scale of infectives approaches the boundary of an attractor basin,epidemic extinction is more likely to occur.The theoretical framework proposed in this study can be extended to the study of other epidemic models.
万方数据
维普
