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arXiv 1708.03025q-bio.PEmath.DS
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建立Wolbachia在蚊虫中传播的模型以控制蚊媒疾病

Modeling the transmission of Wolbachia in mosquitoes for controlling mosquito-borne diseases

Zhuolin Qu, Ling Xue, James M. Hyman

摘要:

我们开发并分析了一个常微分方程模型,以评估用沃尔巴克氏体细菌感染蚊子以控制正在进行的蚊媒流行病(如登革热、基孔肯雅病和寨卡病毒)的潜在有效性。沃尔巴克氏体是一种天然的寄生微生物,可以阻止蚊子体内有害病毒的增殖,减少疾病的传播。在野生蚊子种群中维持母体传播的沃尔巴克氏体的感染是困难的,因为沃尔巴克氏体感染的蚊子的适应性降低和细胞质不相容性限制了母体传播。只有当受感染蚊子的比例超过最低阈值时,感染才会持续。我们的两性蚊子模型通过考虑异性传播、雌性蚊子的多个怀孕状态和水生生命阶段来捕捉复杂的传播周期。我们确定了重要的无量纲数和分析的临界阈值条件获得持续的沃尔巴克氏体感染的自然人群。这种阈值效应的特征在于微分方程系统的三个共存平衡点的后向分支:稳定的无病平衡点,不稳定的中间感染地方病平衡点和稳定的高感染地方病平衡点。我们对流行病学和环境参数进行敏感性分析,以确定它们对沃尔巴克氏体传播和流行的相对重要性。我们还比较了不同的综合缓解策略的有效性,并观察到建立沃尔巴克氏体感染的最有效的方法是首先减少自然蚊子,然后释放受感染的男性和怀孕的女性。自然种群的最初减少可以通过残留喷洒或诱蚊产卵器来实现。

英文摘要:

We develop and analyze an ordinary differential equation model to assess the potential effectiveness of infecting mosquitoes with the Wolbachia bacteria to control the ongoing mosquito-borne epidemics, such as dengue fever, chikungunya, and Zika. Wolbachia is a natural parasitic microbe that stops the proliferation of the harmful viruses inside the mosquito and reduces disease transmission. It is difficult to sustain an infection of the maternal transmitted Wolbachia in a wild mosquito population because of the reduced fitness of the Wolbachia-infected mosquitoes and cytoplasmic incompatibility limiting maternal transmission. The infection will only persist if the fraction of the infected mosquitoes exceeds a minimum threshold. Our two-sex mosquito model captures the complex transmission-cycle by accounting for heterosexual transmission, multiple pregnant states for female mosquitoes, and the aquatic-life stage. We identify important dimensionless numbers and analyze the critical threshold condition for obtaining a sustained Wolbachia infection in the natural population. This threshold effect is characterized by a backward bifurcation with three coexisting equilibria of the system of differential equations: a stable disease-free equilibrium, an unstable intermediate-infection endemic equilibrium and a stable high-infection endemic equilibrium. We perform sensitivity analysis on epidemiological and environmental parameters to determine their relative importance to Wolbachia transmission and prevalence. We also compare the effectiveness of different integrated mitigation strategies and observe that the most efficient approach to establish the Wolbachia infection is to first reduce the natural mosquitoes and then release both infected males and pregnant females. The initial reduction of natural population could be accomplished by either residual spraying or ovitraps.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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