School of Science, Chang'an University, Xi'an, Shaanxi, 710064, China.
Department of Mathematics and Statistics, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.
J Math Biol. 2023 Oct 17;87(5):72. doi: 10.1007/s00285-023-02002-7.
Many infectious diseases cannot be transmitted from human to human directly, and the transmission needs to be done via a vector. It is well known that vectors' life cycles are highly dependent on their living environment. In order to investigate dynamics of vector-borne diseases under environment influence, we propose a vector-borne disease model with almost periodic coefficients. We derive the basic reproductive number [Formula: see text] for this model and establish a threshold type result on its global dynamics in terms of [Formula: see text]. As an illustrative example, we consider an almost periodic model of malaria transmission. Our numerical simulation results show that the basic reproductive number may be underestimated if almost periodic coefficients are replaced by their average values . Finally, we use our model to study the dengue fever transmission in Guangdong, China. The parameters are chosen to fit the reported data available for Guangdong. Numerical simulations indicate that the annual dengue fever case in Guangdong will increase steadily in the near future unless more effective control measures are implemented. Sensitivity analysis implies that the parameters with strong impact on the outcome are recovery rate, mosquito recruitment rate, mosquito mortality rate, baseline transmission rates between mosquito and human. This suggests that the effective control strategies may include intensive treatment, mosquito control, decreasing human contact number with mosquitoes (e.g., using bed nets and preventing mosquito bites), and environmental modification.
许多传染病不能直接在人与人之间传播，其传播需要通过媒介来完成。众所周知，媒介的生命周期高度依赖于其生存环境。为了研究环境影响下的虫媒传染病动力学，我们提出了一个具有几乎周期性系数的虫媒传染病模型。我们推导出了这个模型的基本再生数[Formula: see text]，并基于[Formula: see text]建立了其全局动力学的阈值型结果。作为一个说明性的例子，我们考虑了疟疾传播的一个几乎周期性模型。我们的数值模拟结果表明，如果用平均周期系数代替几乎周期性系数，基本再生数可能会被低估。最后，我们用我们的模型来研究中国广东的登革热传播。参数是根据广东的可用报告数据选择的。数值模拟表明，除非采取更有效的控制措施，否则广东未来的登革热病例数将稳步增加。敏感性分析表明，对结果有强烈影响的参数是恢复率、蚊子繁殖率、蚊子死亡率、蚊子与人类之间的基本传播率。这表明，有效的控制策略可能包括强化治疗、蚊虫控制、减少人与蚊子的接触次数（例如，使用蚊帐和防止蚊虫叮咬）以及环境改造。
