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， 疟疾和其他媒介传播疾病的发病率是一个具有重大公共卫生意义的问题。 因此，迫切需要制定有效的缓解和控制战略。2020年5月，我们进行了试点 乌干达西部农村洪灾后的疟疾化学预防干预。当与两个相邻的 没有部署干预措施的村庄，我们估计减少了53%(ARR 0.47，95%CI 0.34-0.62， P&lt；.01)干预后6个月的疟疾发病率。在这些结果的基础上，科学目标是 这项建议是为了评估有针对性、有时间限制的疟疾化学预防干预措施的有效性。 在有和没有幼虫来源管理(LSM)的情况下，以减少多年生、高风险的疾病负担 严重洪灾后的变速箱设置。我们的前提是干预将减少寄生虫 在关键的“反弹”期间，病媒正在重新建立栖息地，从而维持 传播水平相对较低，直到情况恢复到洪水前的基线。具体来说，我们会： 目的1：确定使用或不使用杀幼虫剂的化学预防效果 为减少严重洪灾后恶性疟发病率的应用。我们将进行一个集群 在乌干达西部农村的50个村庄(144个集群)进行的随机试验，那里的洪水相对可以预测，以 比较：(1)LLIN分配(对照)，(2)LLIN分配加上每月向儿童提供的三轮初级保健 (3)≤+DP，3个月一次，每两周一次，每周一次。 国内空间(DP+Bti)。假设：化学预防将实现持续(≥6个月)的减少 与对照组相比，≥组的疟疾发病率为30%，未出现青蒿素耐药性。 目的2：阐明媒介种群的进化、取食行为和子孢子率 受影响的村庄在洪灾后长达一年。我们将对成年人和青少年进行每周监测 哨兵家庭和家居周边空间中的按蚊。收集到的蚊子将被 计数，并对物种进行鉴定，并检测恶性疟原虫子孢子的存在。假设：洪水 将创造无数的小池子，受到一个人的青睐。冈比亚亚纲复合体形成优势种。冈比亚亚纲 S.S.有可能出现一种新的。阿拉伯作为重要媒介在广泛使用LLIN的背景下 目标3：评估化学预防的相对成本效益(目标3A)并评估社会 和对家庭的经济影响(目标3B)。我们将进行基线和纵向量化 抽样组调查，以评估干预措施对(一)经济活动和收入的影响，(二) 健康寻求和支出，以及(Iii)精神健康和福祉。这些数据将告知成本 化学预防与对照的有效性分析(即避免的每个病例的相对成本)。 假设：化学预防将减轻洪灾后疟疾的负面影响。