The Burden of Chikungunya and Dengue Infection in Kenya

节肢动物传播的病毒，如登革热（DENV）和基孔肯雅热（CHIKV）的爆发，证明了 这些新出现/重新出现的健康威胁对发展中国家和 发达世界。非洲的人口增长、无计划的城市化、栖息地破坏和跨界 旅行可能会导致虫媒病毒爆发的增加。在撒哈拉以南非洲， 对这些疾病的监测只发现了其影响的一小部分， 误诊和未知的传播水平在不同的景观和不同的 易感人群。初步数据显示，肯尼亚儿童和成年人经常 暴露于DENV和CHIKV，在已知爆发之间和期间。我们假设零星的 传播、轻度疾病和/或误诊可能导致对循环的认识不足 在欠发达环境中，仍然有可能发生具有重大经济意义的大规模流行病。我们 建议获得DENV毒株1至4（DENVI-4）的传播和感染估计数， CHIKV穿越肯尼亚。我们的目标是评估CHIKV和DENV相关人类感染的真实负担。 暴露在肯尼亚的两个地区，代表不同的景观，气候和人口，然后 确定传播的空间和时间模式。使用几种新的方法，我们将 1）在两个实验室中量化人类暴露于CHIKV和DENV 1 -4的患病率， 肯尼亚地区。2)检测和预测CHIKV和DENV传播的空间和时间模式 通过将人体循环数据（目标1）与环境和天气/气候相结合， 在现场和利用卫星图像收集的数据。这项研究涉及到了 肯尼亚的Msambweni（沿海）和Masalani（东北部），那里全年都有 虫媒病毒，并基于10年的合作纵向研究。方法包括分析 明确的临床和流行病学发现与病毒免疫生物标志物之间的关系 exposure.在这个项目中，我们将结合以前在肯尼亚海岸和 肯尼亚东北部，以填补关于CHIKV和DENV持续存在的基本知识空白， 自然，包括在流行周期期间驱动持久性的生态因素。然后我们将 将社区一级的人类流行率数据与环境数据相结合，以确定 人类传播。我们计划将气候数据与人类数据进行建模合成， 有助于更好地了解东非的CHIKV和DENV负担和疫情 景观这些知识对于充分了解传播和优化预防至关重要 和控制程序。

Outbreaks of arthropod-borne viruses, such as dengue (DENV) and chikungunya (CHIKV), demonstrate the substantial cost and health burden of these emerging/re-emerging health threats to the developing and developed world. Africa's population growth, unplanned urbanization, habitat destruction, and trans-border travel are likely contributing to a rise in arboviral outbreaks. In sub-Saharan Africa, routine passive surveillance for these diseases detects only a fraction of their impact, given the high probability of misdiagnosis and unknown levels of transmission across different landscapes and within different susceptible populations. Preliminary data demonstrate that Kenyan children and adults are frequently exposed to DENV and CHIKV, both between and during known outbreaks. We hypothesize that sporadic transmission, mild forms of disease, and/or misdiagnosis likely contribute to under-recognition of circulation in less-developed settings, while still leaving potential for large epidemics of major economic importance. We propose to obtain estimates of transmission and infection for DENV strains 1 through 4 (DENVI-4) and CHIKV across Kenya. Our objectives are to assess the true burden of CHIKV- and DENV-related human exposure in two regions of Kenya that represent varied landscape, climate, and populations and then to determine the spatial and temporal patterns of transmission. Using several novel approaches, we will address the following aims: 1) Quantify the prevalence of human exposure to CHIKV and DENV1-4 in two regions of Kenya. 2) Detect and predict spatial and temporal patterns of CHIKV and DENV transmission in rural settings by integrating data on circulation in humans (Aim 1) with environmental and weather/climate data collected both in situ and using satellite imagery. The research involves cohorts in and near Msambweni (coastal) and Masalani (northeastern), Kenya, where there is year-round transmission of arboviruses, and is based on 10 years of collaborative longitudinal studies. Methodologies include analyses of the relationship between well-defined clinical and epidemiologic findings with immune biomarkers of virus exposure. In this project we will couple data from previous long-term studies on the Kenyan coast and in Northeastern Kenya to fill fundamental knowledge gaps about the persistence of CHIKV and DENV in nature, including the ecologic factors that drive persistence during interepidemic cycles. We will then integrate community-level human prevalence data with environmental data to determine the likely drivers of local human transmission. Our planned modeling synthesis of climate data with human data is expected to contribute to improved understanding of CHIKV and DENV burden and outbreaks in the East African landscape. This knowledge is essential for a full understanding of transmission and to optimize prevention and control programs.