The Burden of Chikungunya and Dengue Transmission, Infection and Disease in Kenya

肯尼亚基孔肯雅热和登革热传播、感染和疾病的负担

• 批准号: 8546039
• 负责人: Angelle Desiree LaBeaud
• 金额: $ 68.87万
• 依托单位: CHILDREN'S HOSPITAL & RES CTR AT OAKLAND
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-05 至 2018-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8546039
• 关键词: Acute; Address; Adult; Aedes; Affect; Africa; Africa South of the Sahara; Arboviruses; Arthropods; Attention; Awareness; Behavior; Behavioral; Biological Markers; Blindness; Blood; Blood Circulation; Chikungunya virus; Child; Climate; Clinical; Cognitive deficits; Complex; Culicidae; Data; Dengue; Dengue Virus; Detection; Developed Countries; Diagnosis; Diagnostic; Disease; Disease Outbreaks; Epidemic; Epidemiology; Etiology; Europe; Fever; Future; Habitats; Health; Health Care Costs; Health Resources; Healthcare; Human; Imagery; Immune; In Situ; Incidence; Individual; Infection; International; Kenya; Knowledge; Longitudinal Studies; Maintenance; Maps; Measurement; Measures; Methodology; Modeling; Mosquito Control; Pattern; Population; Population Growth; Populations at Risk; Prevention; Probability; Process; Public Health; Relative (related person); Research; Risk; Risk Assessment; Rural; Salivary; Serum; Syndrome; Testing; Travel; Urbanization; Vaccines; Variant; Viral; Virus; Virus Diseases; Weather; base; biobank; burden of illness; chikungunya; cohort; disorder control; exposed human population; human data; human disease; improved; novel; novel strategies; prevent; programs; prospective; public health relevance; transmission process; vector; vector mosquito

DESCRIPTION (provided by applicant): Outbreaks of arthropod-borne viruses, such as dengue (DENV) and chikungunya (CHIKV) viruses, demonstrate the substantial cost and health burden of these emerging/re-emerging health threats to the developing and developed world. 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. Known and unknown entomologic, environmental, and behavioral factors differentially drive transmission in different habitats. We hypothesize that a significant burden of human disease due to DENV and CHIKV is undetected in the clinical setting, leading to missed opportunities for prevention and heightened risk for large- scale outbreaks. Preliminary data demonstrate that Kenyan children and adults are frequently exposed to DENV and CHIKV, both between and during known outbreaks, although acute arboviral infections are rarely diagnosed in this setting. Our objectives are to assess the true burden of human disease related to DENV strains 1-4 and for CHIKV across Kenya, and then to determine the drivers of viral circulation, estimate the thresholds for outbreak initiation, and provide improved outbreak risk assessment. We will investigate transmission of CHIKV and DENV1-4 in two regions of Kenya that represent heterogeneous degrees of urbanization with varied landscape, climate, and populations. Using several novel approaches, we address the following aims: 1) Quantify the incidence of human infection and disease due to CHIKV and DENV1-4 and determine their relative contribution to acute febrile illness; 2) Measure the level of CHIKV and DENV1- 4 circulation in Aedes mosquito vectors and estimate the amount of human-vector contact in Kenya; and 3) Detect and predict spatial and temporal patterns of CHIKV and DENV transmission in rural and urban settings by integrating data on circulation in humans (Aim 1) and vectors (Aim 2) with environmental and weather/climate data collected both in situ and using satellite imagery. This research involves cohorts in and near Msambweni (coastal) and Kisumu (western), 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 entomologic, clinical, epidemiologic, and climatologic findings and immune biomarkers of virus and mosquito exposure. These studies will fill knowledge gaps about the persistence of CHIKV and DENV in local habitats and the factors that contribute to persistence during inter- epidemic periods and to regional variation during epidemic periods. The data will also answer fundamental questions about arboviral etiologies in severe fever syndromes among at-risk populations while providing better estimates of related disease burden and long-term sequelae.

描述（由申请人提供）：节肢动物传播病毒的爆发，例如登革热（DENV）和奇肯古尼亚（Chikv）病毒，证明了这些新兴/重新出现对发展中和发达国家的健康/重新出现健康威胁的成本和健康负担。在撒哈拉以南非洲，鉴于误诊的可能性很高，并且在不同景观中且在不同的易感人群中，对这些疾病的常规被动监视仅检测到其影响的一小部分。已知且未知的昆虫学，环境和行为因素在不同栖息地中差异化。我们假设在临床环境中未发现由于DENV和CHIKV引起的人类疾病的重大负担，从而导致预防机会错过了，并增加了大规模暴发的风险。初步数据表明，尽管在这种情况下很少诊断出急性急性灰臂感染，但肯尼亚儿童和成人经常在已知爆发之间和爆发期间都暴露于DENV和CHIKV。我们的目标是评估与DENV菌株1-4和整个肯尼亚CHIKV相关的人类疾病的真正负担，然后确定病毒循环的驱动因素，估计爆发爆发的阈值，并提供改进的爆发风险评估。我们将调查Chikv和Denv1-4在肯尼亚的两个地区的传播，这些地区代表了各种景观，气候和人口的异质性城市化程度。使用几种新方法，我们解决了以下目的：1）量化因chikv和denv1-4引起的人类感染和疾病的发生率，并确定它们对急性发热疾病的相对贡献； 2）测量埃德斯蚊子载体中CHIKV和DENV1-4循环的水平，并估计肯尼亚的人类载体接触量； 3）通过将有关人类循环的数据（AIM 1）和向量（AIM 2）与环境和环境和天气/气候数据集成，并使用卫星图像收集到环境和环境/气候数据，从而检测和预测农村和城市环境中CHIKV和DENV传播的空间和时间模式。这项研究涉及肯尼亚的MSAMBWENI（沿海）和Kisumu（沿海）的同伙，那里是Arbovirus的全年传播，并且基于10年的合作纵向研究。方法论包括分析定义明确的昆虫学，临床，流行病学和气候发现以及病毒和蚊子暴露的免疫生物标志物之间的关系。这些研究将填补有关当地栖息地中CHIKV和DENV持续性的知识差距，以及在流行时期持续存在的因素以及在流行病时期内的区域变异。这些数据还将回答有关高危人群中严重发烧综合症的弧病毒病因的基本问题，同时为相关疾病负担和长期后遗症提供更好的估计。