Zika and Dengue Co-circulation Under Environmental Change and Urbanization

摘要：最近在拉丁美洲出现的寨卡病毒已造成150多万例病例， 70个国家，自2013年以来约有1，939例相关的小头畸形病例。人们日益 有证据表明，寨卡病毒（ZIKV）和登革热病毒（DENV），这两种黄病毒具有高水平的 交叉反应性，具有相互依赖的发病趋势，可能是由于宿主免疫和/或 这两种病毒在蚊子感染上的竞争。任何有效性 干预方法将取决于这些共同传播的黄病毒的流行病学。我们 建议在一个新的研究框架内研究这些病毒的时空流行病学关系， 厄瓜多尔北方沿海埃斯梅拉达斯省的一个以前偏远的地区， 一条新公路的建设创造了城市化的梯度。该地区的气候 环境、社会和人口变化在世界范围内发生。我们的项目团队 该地区12年的环境变化和传染病传播数据 我们将以此为基础来帮助解决我们的学习问题。我们的总体目标是 了解ZIKV和DENV传播之间的相互作用以及这种相互作用如何可能 沿着城市化的光谱变化。为了做到这一点，我们建议将流行病学特征 ZIKV和DENV的同时，并创建一个风险模型，将告知干预措施 考虑到病原体相互作用和城市化水平。DENV有一个主要的 媒介传播途径。相比之下，ZIKV具有多种传播途径，例如， 蚊媒和性传播，且蚊种多样，因此相关病因 在更多的农村和更多的城市环境中的组合需要仔细定义， 仔细评估的重要性。我们的总体问题是： ZIKV和DENV共循环背后的机制，以及哪些关键因素（例如，人类 人口密度和多样性、社会网络结构、流动和移徙模式， 基础设施、病媒种群、经济转型）改变了这种相互依赖关系？我们 建议在村庄一级进行纵向研究设计，使我们能够估计登革热， 随着时间的推移，寨卡病毒的发病率。

Abstract: The recent emergence of Zika in Latin America has caused over 1.5 million cases in 70 countries, with some 1,939 related cases of microcephaly since 2013. There is increasing evidence that Zika virus (ZIKV) and Dengue virus (DENV), both flaviviruses with high levels of cross-reactivity, have interdependent incidence trends, possibly due to host immunity and/or competition between the two viruses for mosquito infection. The effectiveness of any intervention approach will depend on the epidemiology of these co-circulating flaviviruses. We propose to examine the spatiotemporal epidemiological relationships of these viruses in a previously remote region in Esmeraldas province of northern coastal Ecuador, where the construction of a new road has created a gradient of urbanicity. This region exemplifies environmental, social, and demographic changes taking place worldwide. Our project team has 12 years of data on environmental change and infectious disease transmission in this region which we will build on to help address our study questions. Our overall objective is to understand the interplay between ZIKV and DENV transmission and how this interplay may change along the urbanicity spectrum. To do this we propose to characterize the epidemiology of both ZIKV and DENV simultaneously and to create a risk model that will inform interventions accounting for pathogen interaction and the level of urbanicity. DENV has one main vectorborne transmission pathway. ZIKV, in contrast, has multiple transmission pathways, e.g., mosquito and sexual transmission, and multiple mosquito species, therefore the relevant causal assemblages in more rural and more urban environments need to be carefully defined and their significance carefully assessed. Our overall question is this: what are the characteristics and mechanisms behind the co-circulation of ZIKV and DENV, and what key factors (e.g., human population density and diversity, social network structure, movement and migration patterns, infrastructure, vector populations, shifting economies) modify this interdependency? We propose a longitudinal study design at the village level that will allow us to estimate dengue and zika incidence over time.