Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes 1374, 05508-900 São Paulo, SP, Brazil.
Department of Global Health and Population, Harvard T. H. Chan School of Public Health, Boston, MA.
J Med Entomol. 2020 May 4;57(3):942-946. doi: 10.1093/jme/tjz220.
Despite historical and contemporary evidence of its effectiveness, larval source management with insecticides remains little used by most malaria control programs worldwide. Here we show that environmentally safe biological larvicides under field conditions can significantly reduce anopheline larval density in fish farming ponds that have became major larval habitats across the Amazon Basin. Importantly, the primary local malaria vector, Anopheles darlingi Root (Diptera: Culicidae), feeds and rests predominantly outdoors, being little affected by interventions such as long-lasting insecticidal bed net distribution and indoor residual spraying. We found >95% reduction in late-instar density up to 7 d after the first application of VectoMax FG or VectoLex CG (both from Valent BioSciences), and up to 21 d after larvicide reapplication in fish ponds (n = 20) situated in the main residual malaria pocket of Brazil, irrespective of the formulation or dosage (10 or 20 kg/ha) used. These results are consistent with a substantial residual effect upon retreatment and support the use of biological larvicides to reduce the density of anopheline larvae in this and similar settings across the Amazon where larval habitats are readily identified and accessible.
尽管有历史和当代的证据表明其有效性，但在全球大多数疟疾控制项目中，幼虫源管理与杀虫剂的结合使用仍然很少。在这里，我们表明，在野外条件下使用环保安全的生物性幼虫杀虫剂，可以显著降低已成为亚马逊盆地主要幼虫栖息地的鱼塘中按蚊幼虫的密度。重要的是，主要的当地疟疾传播媒介，致倦库蚊根（双翅目：蚊科），主要在户外觅食和休息，几乎不受长效杀虫蚊帐分发和室内滞留喷洒等干预措施的影响。我们发现，在第一次使用 VectoMax FG 或 VectoLex CG（均来自 Valent BioSciences）后的 7 天内，晚期幼虫密度降低了超过 95%，在巴西主要的残留疟疾区的鱼塘中，在重新施用杀虫剂后长达 21 天内，幼虫密度降低了超过 95%（n = 20），无论使用的是哪种制剂或剂量（10 或 20 公斤/公顷）。这些结果与再次处理时的大量残留效果一致，并支持在亚马逊地区以及类似地区使用生物性幼虫杀虫剂来降低这种和类似环境中按蚊幼虫的密度，因为这些地区的幼虫栖息地很容易被识别和利用。
