摘要
建立具有接种项且考虑医院病床数的SVIS模型,并对其动力学性态进行了分析。发现:基本再生数R_0是疫苗接种率φ的函数,并且当传染率较大或者病床数目较小时,系统会出现后向分支,即当R_0小于1时,系统会出现两个正平衡点或者无正平衡点;当系统存在两个正平衡点时,其中染病者数量较小的是鞍点,染病者数量较大的为非鞍点。当R_0小于1时,通过增加病床数和减少疾病的传染率,可以消除疾病。
An SVIS model with vaccination and the impact of the number of hospital beds is established,its dynamic behavior is studied. For the model,it is found that the basic reproduction number R_0 is a function of the vaccination φ,and the system undergoes backward bifurcation if the incidence rate is big or the number of beds is small,i. e.,when R_0< 1 there exist two positive equilibria or none in the model. If there exist two positive equilibria,then the lower infected one is a hyperbolic saddle,and the higher one is an anti-saddle. The epidemic can be eliminated by increasing the number of beds or decreasing the value of incidence rate when R_0< 1.
引文
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