Epidemiology of Malaria Risk in Malawi: Vector Resistance, ITNS, and Human Behavior

马拉维疟疾风险的流行病学：病媒耐药性、ITNS 和人类行为

• 批准号: 10385730
• 负责人: Don P Mathanga
• 金额: $ 5.2万
• 依托单位: MICHIGAN STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10385730
• 关键词: Address; Affect; Africa South of the Sahara; Age; Anopheles Genus; Antimalarials; Area; Beds; Behavior; Bite; Breeding; Communities; Country; Culicidae; Devices; Diagnosis; Disease; Drug resistance; Effectiveness; Effectiveness of Interventions; Entomology; Epidemiology; Evaluation; Failure; Frequencies; Goals; Government; Health; Household; Human; Human Activities; Incidence; Individual; Infection; Insecticide Resistance; Insecticides; Interruption; Intervention; Malaria; Malaria prevention; Malawi; Measurable; Measurement; Measures; Monitor; Morbidity - disease rate; Pattern; Persons; Phenotype; Plasmodium falciparum; Population; Population Surveillance; Prevalence; Prevention; Prevention Measures; Probability; Program Effectiveness; Program Research Project Grants; Research; Residual state; Resistance; Risk; Site; Sleep; Study models; Time; Use Effectiveness; Variant; Work; awake; base; burden of illness; cohort; community setting; design; disorder risk; experience; feeding; field study; human disease; improved; infection risk; malaria infection; malaria transmission; multilevel analysis; prevent; programs; pyrethroid; scale up; tool; transmission process; vector; vector transmission

Despite widespread anti-malaria interventions throughout Malawi, including country-wide distribution of insecticide treated nets (ITNs) and free treatment, the burden of malaria remains extremely high, with no measurable decrease in incidence of infection or disease over the past decade. Many factors have been hypothesized to explain such intransigence of malaria in Malawi, and in many parts of sub-Saharan Africa, such as unavailable treatment, drug resistance, improper diagnosis, "silent" reservoirs of infection, and failure of prevention measures. This project, which is integrated with two others in the Malawi ICEMR, addresses the epidemiology of disease risk from the perspective of human-vector interactions as influenced by ITN use and effectiveness and insecticide resistance (IR). We have designed systematic studies to understand why the burden of malaria remains high in Malawi, despite such intense efforts to reduce infection and disease. Our previous work in Malawi has shown that IR is high among major vectors such as Anopheles funestus, and that these mosquitoes are biting before and after usual sleeping time when ITNs could be useful. We hypothesize that ITN effectiveness will vary based on the intensity of transmission, IR, and human and mosquito behaviors. Hence, the goals of this proposed research are: 1) Understand how human infection and disease risk changes with ITN use and effectiveness across diverse environmental contexts and vector-human contact scenarios, 2) Determine how Plasmodium infection in vectors and humans varies with pyrethroid IR and vector behavior across three levels transmission intensity, and 3) Evaluate how human behaviors and biting behavior of Anopheles species alter the entomological inoculation rate (EIR) and human disease risk. To broach these objectives, we will undertake cohort-based, field studies of human and vector populations, measuring infection and disease incidence before, during and after the 2018 Malawi ITN mass distribution campaign. This effort allows us to evaluate the impacts of a massive "experimental" intervention by monitoring effectiveness of interventions and any changes in disease risk. Two cohorts will be established around a government health center in each of the three ecologically and epidemiologically different study sites. The infection cohort will allow measurement of incidence of P. falciparum infection and the disease cohort will be used to assess the incidence of malaria illness. By understanding these factors and their interactions across a range of endemic transmission settings, critical intervention failures can be identified and new strategies to prevent malaria designed. Our results should help improve intervention effectiveness in Malawi, and many other settings in sub-Saharan Africa where malaria burden remains high despite concerted efforts.

尽管整个马拉维都广泛进行反马拉里亚干预，包括 杀虫剂治疗的网（ITN）和免费治疗，疟疾的负担仍然很高，没有 在过去的十年中，感染或疾病的发病率可测量下降。许多因素是 假设可以解释马拉维和撒哈拉以南非洲的许多地方的疟疾的这种顽固性， 例如不可用的治疗，耐药性，诊断不当，感染的“沉默”水库和失败 预防措施。该项目与马拉维ICEMR中的其他两个集成在一起，涉及 从ITN使用和 有效性和杀虫剂耐药性（IR）。我们设计了系统的研究，以了解为什么 尽管努力减少感染和疾病，但马拉维的疟疾负担仍然很高。我们的 马拉维以前的工作表明，在诸如antopheles funestus之类的主要媒介中，IR是很高的，并且 这些蚊子在通常的睡眠时间之前和之后都在咬人，因为ITN可能有用。我们假设 ITN有效性将根据传播，IR和人类和蚊子行为的强度而有所不同。 因此，这项拟议的研究的目标是： 1）了解人类感染和疾病风险如何随着ITN的使用和有效性而变化 各种环境环境和向量人类接触方案， 2）确定载体和人类中的疟原虫感染如何随拟甲虫素IR和载体而变化 跨三个级别的传输强度的行为，以及 3）评估人类的行为和咬人的行为如何改变昆虫学 接种率（EIR）和人类疾病风险。 为了提出这些目标，我们将对人类和向量人群进行基于队列的现场研究， 测量2018年马拉维ITN质量分布之前，期间和之后的感染和疾病发病率 活动。这项工作使我们能够通过监视来评估大规模“实验”干预的影响 干预措施的有效性和疾病风险的任何变化。将建立两个队列 在三个生态和流行病学上不同的研究地点中，政府卫生中心的每个中心。这 感染队列将允许测量恶性疟原虫感染的发病率，疾病队列将是 用于评估疟疾疾病的发生率。通过了解这些因素及其在一个方面的互动 可以确定一系列地方性传输设置，关键干预失败以及新的策略 预防疟疾设计。我们的结果应有助于提高马拉维的干预效率，许多 尽管努力努力，但在撒哈拉以南非洲的其他环境仍然很高。