Anti-larval measures for malaria control in The Gambia

描述(由申请人提供)：建议的研究重点是评估两种幼虫控制剂的能力，球形芽孢杆菌(BS)和苏云金芽孢杆菌变种。以色列(Bti)(VectoLex(R)和Vectobac(R)，Valent Biosciences，美国)减少儿童临床疟疾。有效的疟疾控制正受到热带不同地区药物和杀虫剂耐药性的威胁，而幼虫控制可能为有效控制提供新的替代方案。幼虫控制在历史上是成功的，但在过去50年里在很大程度上被忽视了。最近已证明，前景看好的BS和Bti新配方可以很好地控制非洲疟疾的主要媒介。使用这些产品比使用化学杀幼虫剂更好，因为它们有多种作用，而且当它们一起使用时，似乎不会引起耐药性的演变。到目前为止，很少有试验衡量使用BS和Bti杀幼虫的临床影响，这些试验受到集群内样本量小和缺乏集群复制的阻碍，因此统计能力较低。迫切需要进行一项更大规模的可复制干预研究，以证明控制幼虫是一种有效的疟疾控制工具的概念，并使国际政策制定者能够就控制幼虫的相对优点作出明智的决策。因此，我们建议在冈比亚开展一项大型群组随机干预试验，以调查控制幼虫的能力，以减少儿童疟疾发病率。这项研究的结果将对量化使用苯系物和苯系物在防治疟疾中的重要性作出重大贡献。

DESCRIPTION (provided by applicant): The proposed research focuses on the assessment of the ability of 2 larval control agents, Bacillus sphaericus (Bs) and B. thuringiensis var. israelensis (Bti) (VectoLex(r) and Vectobac(r), Valent Biosciences, USA) to reduce clinical malaria in children. Effective malaria control is under threat from drug and insecticide resistance in different parts of the tropics, and larval control may offer a new alternative for effective control. Larval control has been historically successful, but has been largely neglected over the last 50 years. Promising new formulations of Bs and Bti have recently been shown to give excellent control of the major vectors of malaria in Africa. Use of these products is better than chemical larvicides since they have multiple actions and do not appear to elicit the evolution of resistance when used together. To date few trials have measured the clinical impact of larviciding with Bs and Bti and these have been hampered by small sample size within clusters and a lack of replication of clusters and hence, low statistical power. A larger intervention study with replication is urgently required to demonstrate the proof of concept that larval control is an effective malaria control tool and to allow informed decision making by international policy makers of the relative merits of larval control. We therefore propose to carry out a large cluster-randomised intervention trial in The Gambia to investigate the ability of larval control to reduce malaria morbidity in children. The results from this study will make a major contribution to quantifying the importance of the use of Bs and Bti in the fight against malaria.