Although dengue and Zika cocirculation has increased within the past 5 years, very little is known about its epidemiological consequences. To investigate the effect of dengue and Zika cocirculation on the spread of both pathogens, we create a deterministic dengue and Zika coinfection model, the first to incorporate altered infectivity of mosquitoes (due to coinfection). The model also addresses increased infectivity due to antibody-dependent enhancement (ADE) within the human population. Central to our analysis is the derivation and interpretation of the basic reproductive number and invasion reproductive number of both pathogens. In addition, we investigate how model parameters impact the persistence of each disease. Our results identify threshold conditions under which one disease facilitates the spread of the other and show that ADE has a greater impact on disease persistence than altered vector infectivity. This work highlights the importance of ADE and illustrates that while the endemic presence of dengue facilitates the spread of Zika, it is possible for high Zika prevalence to prevent the establishment of dengue.

中文翻译：

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共感染、改变的载体传染性和抗体依赖性增强：登革热-寨卡病毒相互作用

尽管登革热和寨卡病毒的协同循环在过去 5 年内有所增加，但对其流行病学后果知之甚少。为了研究登革热和寨卡病毒共同循环对两种病原体传播的影响，我们创建了一个确定性登革热和寨卡病毒共感染模型，这是第一个纳入蚊子传染性改变的模型（由于共感染）。该模型还解决了由于人群中抗体依赖性增强 (ADE) 导致的感染性增加。我们分析的核心是两种病原体基本繁殖数和入侵繁殖数的推导和解释。此外，我们研究了模型参数如何影响每种疾病的持续性。我们的结果确定了一种疾病促进另一种疾病传播的阈值条件，并表明 ADE 对疾病持续性的影响比改变的载体传染性更大。这项工作强调了 ADE 的重要性，并说明虽然登革热的流行促进了寨卡病毒的传播，但寨卡病毒的高流行率可能会阻止登革热的形成。