After the flood: Optimal strategies to prevent malaria epidemics caused by severe flooding

洪水过后：预防严重洪水引起的疟疾流行的最佳策略

• 批准号: 10803934
• 负责人: Ross Mathew Boyce
• 金额: $ 99.8万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-08 至 2028-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10803934
• 关键词: 12 year old; Acute; Address; Adolescent; Adult; Affect; Anopheles Genus; Anxiety; Area; Artemisinins; Automobile Driving; Binding; Biological Factors; Blood; Chemoprevention; Child; Cluster randomized trial; Collaborations; Communities; Complex; Cost Effectiveness Analysis; Culicidae; Data; Dedications; Development; Droughts; Economic Burden; Economics; Environment; Epidemic; Evolution; Expenditure; Falciparum Malaria; Feeding behaviors; Floods; Frequencies; Goals; Habitats; Health; Health care facility; Healthcare; Hospitalization; Household; Human; Incidence; Income; Intervention; Knowledge; Laboratories; Malaria; Mental Health; National Institute of Allergy and Infectious Disease; Parasites; Personal Satisfaction; Phase; Plasmodium falciparum; Population; Public Health; Research; Resistance; Rural; Sampling; Schools; Scientist; Seasons; Sentinel; Site; Social Impacts; Social outcome; Source; Sporozoites; Surface; Surveys; Temperature; Testing; Time; Training; Uganda; United States National Institutes of Health; Vector-transmitted infectious disease; Work; arm; burden of illness; climate change; climate impact; comparison control; cost effectiveness; economic impact; economic outcome; effectiveness evaluation; extreme weather; feeding; health economics; malaria transmission; new epidemic; post intervention; prevent; preventive intervention; primary outcome; relative cost; social factors; socioeconomics; tool; transmission process; uptake; vector

PROJECT SUMMARY/ABSTRACT The impact of climate change, including the increased frequency of weather extremes such as flooding, on the incidence of malaria and other vector-borne diseases is an issue of substantial public health importance. Therefore, there is an urgent need to develop effective mitigation and control strategies. In May 2020, we piloted a post-flood malaria chemoprevention intervention in rural western Uganda. When compared to two neighboring villages where no intervention was deployed, we estimated a 53% reduction (aRR 0.47, 95% CI 0.34 – 0.62, p<.01) in malaria incidence in the six months post-intervention. Building on these results, the scientific aim of this proposal is to evaluate the effectiveness of a targeted, time-limited malaria chemoprevention intervention with and without larval source management (LSM) to reduce excess disease burden in a perennial, high- transmission setting following severe flooding. Our premise is that the intervention will reduce the parasite reservoir during the critical “rebound” period, when vectors are re-establishing habitats thereby maintaining relatively low levels of transmission until conditions have returned to the pre-flood baseline. Specifically, we will: Aim 1: Determine the effectiveness of chemoprevention with or without peri-domestic larvicide application to reduce the incidence of P. falciparum malaria after severe flooding. We will conduct a cluster randomized trial in 50 villages (144 clusters) in rural western Uganda, where flooding relatively predictable, to compare: (i) LLIN distribution (control), (ii) LLIN distribution plus three, monthly rounds of DP provided to children ≤12 years of age (DP), and (iii) LLIN+DP with three months of bi-weekly application of larvicide in the peri- domestic space (DP+Bti). Hypothesis: Chemoprevention will achieve a sustained (≥6 months) reduction in malaria incidence of ≥30% compared to the control arm without the emergence of artemisinin resistance. Aim 2: Elucidate the evolution of vector populations, feeding behaviors, and sporozoite rate in affected villages up to one year after flooding. We will perform weekly surveillance for adult and juvenile Anopheles mosquitoes in sentinel households and within the peri-domestic space. Collected mosquitoes will be counted, and identified to species and tested for the presence of P. falciparum sporozoites. Hypothesis: Flooding will create innumerable small pools favored by An. gambiae complex resulting in predominance of An. gambiae s.s. with potential for emergence of An. arabiensis as important vector in setting of widespread LLIN use.23 Aim 3: Evaluate the relative cost-effectiveness of chemoprevention (Aim 3A) and assess social and economic impacts on households (Aim 3B). We will conduct baseline and longitudinal quantitative surveys in sample clusters to evaluate impacts of the interventions on (i) economic activities and income, (ii) health seeking and expenditures, and (iii) mental health and well-being. These data will inform a cost effectiveness analysis of chemoprevention compared to the control (i.e., relative cost per case averted). Hypothesis: Chemoprevention will mitigate negative effects of malaria in the aftermath of a flood.

项目摘要/摘要 气候变化的影响，包括洪水等极端天气的频率增加， 关于疟疾和其他媒介传播疾病的事件，公共健康重要性是一个重要的问题。 因此，迫切需要制定有效的缓解和控制策略。 2020年5月，我们驾驶 乌干达乡村的洪水后化学预防干预。与两个相邻 没有部署干预的村庄，我们估计减少了53％（ARR 0.47，95％CI 0.34 - 0.62， p <.01）干预后六个月内发生疟疾发病率。在这些结果的基础上，科学目的 该建议是评估有针对性的，时限的疟疾化学预防干预的有效性 有和没有幼虫来源管理（LSM），以减轻多年生，高的疾病负担 严重洪水后的传输设置。我们的前提是干预将减少寄生虫 在关键的“反弹”时期的水库，当时向量重新建立栖息地，从而维护 相关的低水平传输水平，直到条件恢复为液体前基线。具体来说，我们将： AIM 1：确定具有或不含肉周内幼虫的化学预防的有效性 在严重洪水后，适用于减少恶性疟原虫疟疾的发生率。我们将进行集群 乌干达乡村的50个村庄（144个集群）的随机试验，洪水相对可预测， 比较：（i）LLIN分布（对照），（ii）Llin分布以及提供给儿童的三个每月回合的DP ≤12岁（DP）和（iii）LLIN+DP，每两个月在周期施用幼虫三个月 国内空间（DP+BTI）。假设：化学预防将减少（≥6个月） 与对照组相比，疟疾的入射率≥30％，而无需青蒿素耐药性。 AIM 2：阐明矢量种群，进食行为和孢子岩速率的演变 洪水后长达一年的村庄影响了村庄。我们将对成人和少年进行每周的监视 哨兵户家庭和周围空间内的蚊子蚊子。收集的蚊子将是 计算并确定为物种，并测试了恶性疟原虫孢子菌的存在。假设：洪水 将创建无数的小型游泳池。冈比亚复合物导致an。冈比亚 S.S.有可能出现的。阿拉伯语作为设置宽度llin的重要矢量。23 目标3：评估化学预防的相对成本效益（AIM 3A）并评估社会 和对家庭的经济影响（AIM 3B）。我们将进行基线和纵向定量 样本簇中的调查以评估干预措施对（i）经济活动和收入的影响，（ii） 健康寻求和支出，以及（iii）心理健康和福祉。这些数据将为费用提供信息 与对照相比，化学预防的有效性分析（即，避免每例病例的相对成本）。 假设：化学预防会减轻洪水后疟疾的负面影响。